Breast Cancer

Key clinical point: Anlotinib combined with chemotherapy demonstrated good activity in the treatment of metastatic triple-negative breast cancer (TNBC) along with an acceptable safety profile in a single-arm phase 2 study.

Major finding: The median progression-free survival was 8.8 months (95% CI 6.5-11.1 months), and the median overall survival was 19.0 months (95% CI 12.1-25.9 months). Grade 3-4 treatment-related adverse events (TRAE) included neutropenia (22.5%), leukopenia (20.0%), secondary hypertension (10.0%), hand-foot syndrome (5.0%), vomiting (5.0%), proteinuria (5.0%), and thrombocytopenia (2.5%), and no deaths due to TRAE were reported.

Study details: Findings are from a prospective phase 2 trial including 40 patients with metastatic TNBC who were previously treated with anthracycline or taxane and received anlotinib combined with chemotherapy.

Disclosures: This study received funding support from the Shenzhen Basic Research Program, China, and the National Natural Science Foundation of China. The authors declared no conflicts of interest.

Source: Huang JY et al. A single-arm phase II clinical trial of anlotinib combined with chemotherapy for the treatment of metastatic triple-negative breast cancer. Front Oncol. 2023;13:1122294 (Apr 12). Doi: 10.3389/fonc.2023.1122294

Key clinical point: Anlotinib combined with chemotherapy demonstrated good activity in the treatment of metastatic triple-negative breast cancer (TNBC) along with an acceptable safety profile in a single-arm phase 2 study.

Major finding: The median progression-free survival was 8.8 months (95% CI 6.5-11.1 months), and the median overall survival was 19.0 months (95% CI 12.1-25.9 months). Grade 3-4 treatment-related adverse events (TRAE) included neutropenia (22.5%), leukopenia (20.0%), secondary hypertension (10.0%), hand-foot syndrome (5.0%), vomiting (5.0%), proteinuria (5.0%), and thrombocytopenia (2.5%), and no deaths due to TRAE were reported.

Study details: Findings are from a prospective phase 2 trial including 40 patients with metastatic TNBC who were previously treated with anthracycline or taxane and received anlotinib combined with chemotherapy.

Disclosures: This study received funding support from the Shenzhen Basic Research Program, China, and the National Natural Science Foundation of China. The authors declared no conflicts of interest.

Source: Huang JY et al. A single-arm phase II clinical trial of anlotinib combined with chemotherapy for the treatment of metastatic triple-negative breast cancer. Front Oncol. 2023;13:1122294 (Apr 12). Doi: 10.3389/fonc.2023.1122294

Key clinical point: Anlotinib combined with chemotherapy demonstrated good activity in the treatment of metastatic triple-negative breast cancer (TNBC) along with an acceptable safety profile in a single-arm phase 2 study.

Major finding: The median progression-free survival was 8.8 months (95% CI 6.5-11.1 months), and the median overall survival was 19.0 months (95% CI 12.1-25.9 months). Grade 3-4 treatment-related adverse events (TRAE) included neutropenia (22.5%), leukopenia (20.0%), secondary hypertension (10.0%), hand-foot syndrome (5.0%), vomiting (5.0%), proteinuria (5.0%), and thrombocytopenia (2.5%), and no deaths due to TRAE were reported.

Study details: Findings are from a prospective phase 2 trial including 40 patients with metastatic TNBC who were previously treated with anthracycline or taxane and received anlotinib combined with chemotherapy.

Disclosures: This study received funding support from the Shenzhen Basic Research Program, China, and the National Natural Science Foundation of China. The authors declared no conflicts of interest.

Source: Huang JY et al. A single-arm phase II clinical trial of anlotinib combined with chemotherapy for the treatment of metastatic triple-negative breast cancer. Front Oncol. 2023;13:1122294 (Apr 12). Doi: 10.3389/fonc.2023.1122294

Key clinical point: Targeted axillary dissection (TAD) by marking the metastatic lymph node with ¹²⁵I seeds before neoadjuvant chemotherapy (NACT) showed excellent identification rates and ruled out the need for remarking before surgery.

Major finding: The identification rates of the marked lymph node (MLN) and sentinel node (SN) were 99.3% and 91.5%, respectively, with the TAD procedure being successful in 91.5% of patients based on the identification of both MLN and SN. Overall, 40.8% of patients achieved axillary pathologic complete response and could be spared from surgery.

Study details: Findings are from a cohort study including 142 patients with BC who underwent TAD after ¹²⁵I seeds were placed before NACT.

Disclosures: This study was funded by Helsefonden. The authors did not report conflicts of interest.

Source: Munck F et al. Targeted axillary dissection with ¹²⁵I seed placement before neoadjuvant chemotherapy in a Danish multicenter cohort. Ann Surg Oncol. 2023 (Apr 16). Doi: 10.1245/s10434-023-13432-4

Key clinical point: Targeted axillary dissection (TAD) by marking the metastatic lymph node with ¹²⁵I seeds before neoadjuvant chemotherapy (NACT) showed excellent identification rates and ruled out the need for remarking before surgery.

Major finding: The identification rates of the marked lymph node (MLN) and sentinel node (SN) were 99.3% and 91.5%, respectively, with the TAD procedure being successful in 91.5% of patients based on the identification of both MLN and SN. Overall, 40.8% of patients achieved axillary pathologic complete response and could be spared from surgery.

Study details: Findings are from a cohort study including 142 patients with BC who underwent TAD after ¹²⁵I seeds were placed before NACT.

Disclosures: This study was funded by Helsefonden. The authors did not report conflicts of interest.

Source: Munck F et al. Targeted axillary dissection with ¹²⁵I seed placement before neoadjuvant chemotherapy in a Danish multicenter cohort. Ann Surg Oncol. 2023 (Apr 16). Doi: 10.1245/s10434-023-13432-4

Key clinical point: Targeted axillary dissection (TAD) by marking the metastatic lymph node with ¹²⁵I seeds before neoadjuvant chemotherapy (NACT) showed excellent identification rates and ruled out the need for remarking before surgery.

Major finding: The identification rates of the marked lymph node (MLN) and sentinel node (SN) were 99.3% and 91.5%, respectively, with the TAD procedure being successful in 91.5% of patients based on the identification of both MLN and SN. Overall, 40.8% of patients achieved axillary pathologic complete response and could be spared from surgery.

Study details: Findings are from a cohort study including 142 patients with BC who underwent TAD after ¹²⁵I seeds were placed before NACT.

Disclosures: This study was funded by Helsefonden. The authors did not report conflicts of interest.

Source: Munck F et al. Targeted axillary dissection with ¹²⁵I seed placement before neoadjuvant chemotherapy in a Danish multicenter cohort. Ann Surg Oncol. 2023 (Apr 16). Doi: 10.1245/s10434-023-13432-4

Key clinical point: Pretreatment tumor stage and nodal involvement could predict the risk for disease relapse in patients with human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (BC) who had achieved pathologic complete response (pCR) with neoadjuvant chemotherapy plus anti-HER2 therapy.

Major finding: Patients who did vs did not achieve pCR had prolonged event-free survival (EFS; hazard ratio [HR] 0.39) and overall survival (HR 0.32; both P < .001). However, in patients with pCR, higher pretreatment tumor stage (cT3-4 vs cT1-2; P = .007) and presence of nodal involvement (cN+ vs cN−; P = .039) could worsen EFS.

Study details: This study analyzed the data of 3710 patients with HER2+ early BC from 11 trials who had received neoadjuvant chemotherapy+anti-HER2 therapy, of which 40.4% of patients had achieved pCR.

Disclosures: This study was supported by author Sibylle Loibl. Several authors declared serving as consultants or advisors, receiving honoraria or research funding, or having other ties with various sources.

Source: van Mackelenbergh MT et al on behalf of the CTNeoBC project. Pathologic complete response and individual patient prognosis after neoadjuvant chemotherapy plus anti-human epidermal growth factor receptor 2 therapy of human epidermal growth factor receptor 2-positive early breast cancer. J Clin Oncol. 2023 (Apr 19). Doi: 10.1200/JCO.22.02241

Key clinical point: Pretreatment tumor stage and nodal involvement could predict the risk for disease relapse in patients with human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (BC) who had achieved pathologic complete response (pCR) with neoadjuvant chemotherapy plus anti-HER2 therapy.

Major finding: Patients who did vs did not achieve pCR had prolonged event-free survival (EFS; hazard ratio [HR] 0.39) and overall survival (HR 0.32; both P < .001). However, in patients with pCR, higher pretreatment tumor stage (cT3-4 vs cT1-2; P = .007) and presence of nodal involvement (cN+ vs cN−; P = .039) could worsen EFS.

Study details: This study analyzed the data of 3710 patients with HER2+ early BC from 11 trials who had received neoadjuvant chemotherapy+anti-HER2 therapy, of which 40.4% of patients had achieved pCR.

Disclosures: This study was supported by author Sibylle Loibl. Several authors declared serving as consultants or advisors, receiving honoraria or research funding, or having other ties with various sources.

Source: van Mackelenbergh MT et al on behalf of the CTNeoBC project. Pathologic complete response and individual patient prognosis after neoadjuvant chemotherapy plus anti-human epidermal growth factor receptor 2 therapy of human epidermal growth factor receptor 2-positive early breast cancer. J Clin Oncol. 2023 (Apr 19). Doi: 10.1200/JCO.22.02241

Key clinical point: Pretreatment tumor stage and nodal involvement could predict the risk for disease relapse in patients with human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (BC) who had achieved pathologic complete response (pCR) with neoadjuvant chemotherapy plus anti-HER2 therapy.

Major finding: Patients who did vs did not achieve pCR had prolonged event-free survival (EFS; hazard ratio [HR] 0.39) and overall survival (HR 0.32; both P < .001). However, in patients with pCR, higher pretreatment tumor stage (cT3-4 vs cT1-2; P = .007) and presence of nodal involvement (cN+ vs cN−; P = .039) could worsen EFS.

Study details: This study analyzed the data of 3710 patients with HER2+ early BC from 11 trials who had received neoadjuvant chemotherapy+anti-HER2 therapy, of which 40.4% of patients had achieved pCR.

Disclosures: This study was supported by author Sibylle Loibl. Several authors declared serving as consultants or advisors, receiving honoraria or research funding, or having other ties with various sources.

Source: van Mackelenbergh MT et al on behalf of the CTNeoBC project. Pathologic complete response and individual patient prognosis after neoadjuvant chemotherapy plus anti-human epidermal growth factor receptor 2 therapy of human epidermal growth factor receptor 2-positive early breast cancer. J Clin Oncol. 2023 (Apr 19). Doi: 10.1200/JCO.22.02241

Key clinical point: The incidence rate of squamous cell carcinoma (SCC) was extremely low and, hence, of minimal public health concern in patients with non-SCC breast cancer (BC) or carcinoma in situ who underwent implant-based reconstruction.

Major finding: Only 1 woman was diagnosed with SCC after 52 months of BC diagnosis. The incidence rate of SCC after implant-based reconstruction was extremely low (2.37 per million person-years) and was not significantly higher in women with BC than in the general population (standardized incidence ratio 2.33; 95% CI 0.06-13.0).

Study details: Findings are from a cohort study including 56,785 women with BC or carcinoma in situ who underwent cancer-directed mastectomy with implant reconstruction.

Disclosures: This study was supported by the US National Cancer Institute. Some authors declared receiving personal fees or grants or having other ties with several sources.

Source: Kinslow CJ et al. Risk of squamous cell carcinoma of the breast following postmastectomy implant reconstruction in women with breast cancer and carcinoma in situ. JAMA Surg. 2023 (Apr 19). Doi: 10.1001/jamasurg.2023.0262 

Key clinical point: The incidence rate of squamous cell carcinoma (SCC) was extremely low and, hence, of minimal public health concern in patients with non-SCC breast cancer (BC) or carcinoma in situ who underwent implant-based reconstruction.

Major finding: Only 1 woman was diagnosed with SCC after 52 months of BC diagnosis. The incidence rate of SCC after implant-based reconstruction was extremely low (2.37 per million person-years) and was not significantly higher in women with BC than in the general population (standardized incidence ratio 2.33; 95% CI 0.06-13.0).

Study details: Findings are from a cohort study including 56,785 women with BC or carcinoma in situ who underwent cancer-directed mastectomy with implant reconstruction.

Disclosures: This study was supported by the US National Cancer Institute. Some authors declared receiving personal fees or grants or having other ties with several sources.

Source: Kinslow CJ et al. Risk of squamous cell carcinoma of the breast following postmastectomy implant reconstruction in women with breast cancer and carcinoma in situ. JAMA Surg. 2023 (Apr 19). Doi: 10.1001/jamasurg.2023.0262 

Key clinical point: The incidence rate of squamous cell carcinoma (SCC) was extremely low and, hence, of minimal public health concern in patients with non-SCC breast cancer (BC) or carcinoma in situ who underwent implant-based reconstruction.

Major finding: Only 1 woman was diagnosed with SCC after 52 months of BC diagnosis. The incidence rate of SCC after implant-based reconstruction was extremely low (2.37 per million person-years) and was not significantly higher in women with BC than in the general population (standardized incidence ratio 2.33; 95% CI 0.06-13.0).

Study details: Findings are from a cohort study including 56,785 women with BC or carcinoma in situ who underwent cancer-directed mastectomy with implant reconstruction.

Disclosures: This study was supported by the US National Cancer Institute. Some authors declared receiving personal fees or grants or having other ties with several sources.

Source: Kinslow CJ et al. Risk of squamous cell carcinoma of the breast following postmastectomy implant reconstruction in women with breast cancer and carcinoma in situ. JAMA Surg. 2023 (Apr 19). Doi: 10.1001/jamasurg.2023.0262 

Key clinical point: Adherence to the American Institute for Cancer Research and American Cancer Society’s lifestyle recommendations reduced the risk for disease recurrence and improved mortality in patients with high-risk breast cancer (BC).

Major finding: Patients in the highest vs lowest tertile of lifestyle index scores (LIS) experienced a 37% reduction in recurrence (hazard ratio [HR] 0.63; 95% CI 0.48-0.82) and those in the middle (HR 0.70; P = .03) and highest (HR 0.42; P < .001) vs lowest tertile of LIS had significant reductions in mortality.

Study details: Findings are from the prospective, observational, DELCaP (The Diet, Exercise, Lifestyles, and Cancer Prognosis) study including 1340 chemotherapy-naive women with high-risk stage I to III BC, of which the majority (65.3%) of women had hormone receptor-positive BC.

Disclosures: This study was supported by the US National Cancer Institute and The Breast Cancer Research Foundation, New York Some authors declared serving as members of independent data monitoring committees or receiving grants or personal fees from several sources.

Source: Cannioto RA et al. Adherence to cancer prevention lifestyle recommendations before, during, and 2 years after treatment for high-risk breast cancer. JAMA Netw Open. 2023;6(5):e2311673 (May 4). Doi: 10.1001/jamanetworkopen.2023.11673

Key clinical point: Adherence to the American Institute for Cancer Research and American Cancer Society’s lifestyle recommendations reduced the risk for disease recurrence and improved mortality in patients with high-risk breast cancer (BC).

Major finding: Patients in the highest vs lowest tertile of lifestyle index scores (LIS) experienced a 37% reduction in recurrence (hazard ratio [HR] 0.63; 95% CI 0.48-0.82) and those in the middle (HR 0.70; P = .03) and highest (HR 0.42; P < .001) vs lowest tertile of LIS had significant reductions in mortality.

Study details: Findings are from the prospective, observational, DELCaP (The Diet, Exercise, Lifestyles, and Cancer Prognosis) study including 1340 chemotherapy-naive women with high-risk stage I to III BC, of which the majority (65.3%) of women had hormone receptor-positive BC.

Disclosures: This study was supported by the US National Cancer Institute and The Breast Cancer Research Foundation, New York Some authors declared serving as members of independent data monitoring committees or receiving grants or personal fees from several sources.

Source: Cannioto RA et al. Adherence to cancer prevention lifestyle recommendations before, during, and 2 years after treatment for high-risk breast cancer. JAMA Netw Open. 2023;6(5):e2311673 (May 4). Doi: 10.1001/jamanetworkopen.2023.11673

Key clinical point: Adherence to the American Institute for Cancer Research and American Cancer Society’s lifestyle recommendations reduced the risk for disease recurrence and improved mortality in patients with high-risk breast cancer (BC).

Major finding: Patients in the highest vs lowest tertile of lifestyle index scores (LIS) experienced a 37% reduction in recurrence (hazard ratio [HR] 0.63; 95% CI 0.48-0.82) and those in the middle (HR 0.70; P = .03) and highest (HR 0.42; P < .001) vs lowest tertile of LIS had significant reductions in mortality.

Study details: Findings are from the prospective, observational, DELCaP (The Diet, Exercise, Lifestyles, and Cancer Prognosis) study including 1340 chemotherapy-naive women with high-risk stage I to III BC, of which the majority (65.3%) of women had hormone receptor-positive BC.

Disclosures: This study was supported by the US National Cancer Institute and The Breast Cancer Research Foundation, New York Some authors declared serving as members of independent data monitoring committees or receiving grants or personal fees from several sources.

Source: Cannioto RA et al. Adherence to cancer prevention lifestyle recommendations before, during, and 2 years after treatment for high-risk breast cancer. JAMA Netw Open. 2023;6(5):e2311673 (May 4). Doi: 10.1001/jamanetworkopen.2023.11673

Key clinical point: Breast cancer (BC) recurrence rates are lower among patients treated with the combination of anthracycline and taxane compared with a taxane regimen without anthracycline or an anthracycline-based regimen without taxane.

Major finding: Anthracycline plus taxane reduced the rate of BC recurrence by 14% (rate ratio [RR] 0.86; P = .0004) compared with taxane only and by 13% (RR 0.87; P < .0001) compared with anthracycline only. The highest benefit was observed among patients receiving anthracycline concurrently with docetaxel+cyclophosphamide vs docetaxel+cyclophosphamide only (RR 0.58; P < .0001).

Study details: Findings are from a meta-analysis including more than 100,000 women with early-stage BC from 86 trials on anthracycline- and taxane-based chemotherapies.

Disclosures: This study is funded by Cancer Research UK. The authors declared receiving grants, payments, honoraria, consulting fees, or travel support from or having other ties with various sources.

Source: Early Breast Cancer Trialists' Collaborative Group. Anthracycline-containing and taxane-containing chemotherapy for early-stage operable breast cancer: A patient-level meta-analysis of 100 000 women from 86 randomised trials. Lancet. 2023;401(10384):1277-1292 (Apr 15). Doi: 10.1016/S0140-6736(23)00285-4

Key clinical point: Breast cancer (BC) recurrence rates are lower among patients treated with the combination of anthracycline and taxane compared with a taxane regimen without anthracycline or an anthracycline-based regimen without taxane.

Major finding: Anthracycline plus taxane reduced the rate of BC recurrence by 14% (rate ratio [RR] 0.86; P = .0004) compared with taxane only and by 13% (RR 0.87; P < .0001) compared with anthracycline only. The highest benefit was observed among patients receiving anthracycline concurrently with docetaxel+cyclophosphamide vs docetaxel+cyclophosphamide only (RR 0.58; P < .0001).

Study details: Findings are from a meta-analysis including more than 100,000 women with early-stage BC from 86 trials on anthracycline- and taxane-based chemotherapies.

Disclosures: This study is funded by Cancer Research UK. The authors declared receiving grants, payments, honoraria, consulting fees, or travel support from or having other ties with various sources.

Source: Early Breast Cancer Trialists' Collaborative Group. Anthracycline-containing and taxane-containing chemotherapy for early-stage operable breast cancer: A patient-level meta-analysis of 100 000 women from 86 randomised trials. Lancet. 2023;401(10384):1277-1292 (Apr 15). Doi: 10.1016/S0140-6736(23)00285-4

Key clinical point: Breast cancer (BC) recurrence rates are lower among patients treated with the combination of anthracycline and taxane compared with a taxane regimen without anthracycline or an anthracycline-based regimen without taxane.

Major finding: Anthracycline plus taxane reduced the rate of BC recurrence by 14% (rate ratio [RR] 0.86; P = .0004) compared with taxane only and by 13% (RR 0.87; P < .0001) compared with anthracycline only. The highest benefit was observed among patients receiving anthracycline concurrently with docetaxel+cyclophosphamide vs docetaxel+cyclophosphamide only (RR 0.58; P < .0001).

Study details: Findings are from a meta-analysis including more than 100,000 women with early-stage BC from 86 trials on anthracycline- and taxane-based chemotherapies.

Disclosures: This study is funded by Cancer Research UK. The authors declared receiving grants, payments, honoraria, consulting fees, or travel support from or having other ties with various sources.

Source: Early Breast Cancer Trialists' Collaborative Group. Anthracycline-containing and taxane-containing chemotherapy for early-stage operable breast cancer: A patient-level meta-analysis of 100 000 women from 86 randomised trials. Lancet. 2023;401(10384):1277-1292 (Apr 15). Doi: 10.1016/S0140-6736(23)00285-4

Key clinical point: Temporarily discontinuing endocrine therapy (ET) to attempt pregnancy did not increase the recurrence risk for breast cancer (BC) in young women with early hormone receptor-positive (HR+) BC.

Major finding: After a median follow-up of 41 months, 44 patients had BC and the incidence of BC events was not higher among patients who interrupted ET vs control individuals with BC from an external cohort who received treatment with different adjuvant endocrine strategies (hazard ratio 0.81; 95% CI 0.57-1.15). Pregnancy was reported by 368 patients and 317 patients had ≥1 live birth.

Study details: Findings are from a single-group trial including 516 premenopausal women aged ≤42 years with stage I, II, or III HR+ BC treated with ET for 18-30 months who discontinued ET to attempt pregnancy.

Disclosures: This study was supported by the ETOP IBCSG Partners Foundation and other sources. Some authors declared serving as consultants; receiving grants, contracts, or travel support; or having other ties with several sources.

Source: Partridge AH et al for the International Breast Cancer Study Group, and the POSITIVE Trial Collaborators. Interrupting endocrine therapy to attempt pregnancy after breast cancer. N Engl J Med. 2023;388(18):1645-1656 (May 4). Doi: 10.1056/NEJMoa2212856

Key clinical point: Temporarily discontinuing endocrine therapy (ET) to attempt pregnancy did not increase the recurrence risk for breast cancer (BC) in young women with early hormone receptor-positive (HR+) BC.

Major finding: After a median follow-up of 41 months, 44 patients had BC and the incidence of BC events was not higher among patients who interrupted ET vs control individuals with BC from an external cohort who received treatment with different adjuvant endocrine strategies (hazard ratio 0.81; 95% CI 0.57-1.15). Pregnancy was reported by 368 patients and 317 patients had ≥1 live birth.

Study details: Findings are from a single-group trial including 516 premenopausal women aged ≤42 years with stage I, II, or III HR+ BC treated with ET for 18-30 months who discontinued ET to attempt pregnancy.

Disclosures: This study was supported by the ETOP IBCSG Partners Foundation and other sources. Some authors declared serving as consultants; receiving grants, contracts, or travel support; or having other ties with several sources.

Source: Partridge AH et al for the International Breast Cancer Study Group, and the POSITIVE Trial Collaborators. Interrupting endocrine therapy to attempt pregnancy after breast cancer. N Engl J Med. 2023;388(18):1645-1656 (May 4). Doi: 10.1056/NEJMoa2212856

Key clinical point: Temporarily discontinuing endocrine therapy (ET) to attempt pregnancy did not increase the recurrence risk for breast cancer (BC) in young women with early hormone receptor-positive (HR+) BC.

Major finding: After a median follow-up of 41 months, 44 patients had BC and the incidence of BC events was not higher among patients who interrupted ET vs control individuals with BC from an external cohort who received treatment with different adjuvant endocrine strategies (hazard ratio 0.81; 95% CI 0.57-1.15). Pregnancy was reported by 368 patients and 317 patients had ≥1 live birth.

Study details: Findings are from a single-group trial including 516 premenopausal women aged ≤42 years with stage I, II, or III HR+ BC treated with ET for 18-30 months who discontinued ET to attempt pregnancy.

Disclosures: This study was supported by the ETOP IBCSG Partners Foundation and other sources. Some authors declared serving as consultants; receiving grants, contracts, or travel support; or having other ties with several sources.

Source: Partridge AH et al for the International Breast Cancer Study Group, and the POSITIVE Trial Collaborators. Interrupting endocrine therapy to attempt pregnancy after breast cancer. N Engl J Med. 2023;388(18):1645-1656 (May 4). Doi: 10.1056/NEJMoa2212856

The results from a prognostic genomic assay called HER2DX convinced a group of Spanish oncologists to change treatment plans for 56% of 89 patients with HER2-positive (HER2+) early breast cancer, according to new research.

The prospective pilot study is small, and the researchers didn’t report on how the patients fared, according to a poster presented at the European Society for Medical Oncology (ESMO) Breast Cancer annual congress. Plus, the test itself hasn’t been analyzed prospectively. But the study’s lead author, Olga Martínez-Sáez, MD, PhD, said in an interview that the 56% number is significant.

“We consider this percentage to be clinically very relevant,” said Dr. Martínez-Sáez, an oncologist at Hospital Clinic of Barcelona and the University of Barcelona. “HER2DX can change practice.”

Also in an interview, Kent Hoskins, MD, associate chief of hematology/oncology at University of Illinois at Chicago, described HER2DX as a next-generation genomic test that builds on assays developed 2 decades ago to help identify patients who would benefit – or not – from adjuvant chemotherapy.

Dr. Hoskins, who isn’t connected to the new study but has studied genomic tests for breast cancer, said the HER2DX test seeks to provide guidance to oncologists about which of several treatments are most effective in treating patients with HER2+ breast cancer.

“The overall trend in the HER2+ space is escalating therapy, and the cure rates have improved quite substantially,” he said. “But do they all need that much therapy? That’s the clinical question that this assay is addressing.”

The assay examines clinical features and the expression of 4 gene signatures, Dr. Martínez-Sáez said. It provides a risk score estimating the likelihood of recurrence plus a score that estimates the likelihood of achieving pathological complete response (pCR) with trastuzumab-based neoadjuvant therapy and an ERBB2 mRNA score.

In a retrospective 2022 study published in eBioMedicine, researchers reported that the assay “predicts response following neoadjuvant letrozole in combination with dual HER2 blockade with trastuzumab and pertuzumab in early-stage HER2-positive/hormone receptor–positive breast cancer.”

In the 2022 study, researchers wrote that assay results and other scores “might help better tailor systemic therapy in this context and identify candidates for avoiding chemotherapy, a therapy associated with short- and long-term toxicities and impact in quality of life.”

For the new study, a decision-impact analysis, researchers tracked 89 patients with HER2+ breast cancer (median age = 53 years, range 30-79, and 52% postmenopausal), the poster says. Most had T1-2 tumors (87%), negative nodes (64%), grade 2 (56%) or 3 (41%) tumors, and ductal histology (87%). And most were hormone receptor positive (65%). Seventy-eight percent of patients received neoadjuvant therapy (NAT), and 22% underwent upfront surgery.

In 56% of cases, oncologists changed their treatment decisions after getting the results of the HER2DX assays. In 59% of these cases, oncologists de-escalated therapy; in 41%, they escalated therapy, opting for more intense chemotherapy 65% of the time, according to the poster.

Clinician confidence in their decisions improved in 67% of cases, the researchers reported in their poster. Among 56 patients treated with neoadjuvant therapy who could be evaluated, “HER2DX pCR score was significantly associated with pCR (81% in pCR-medium/high and 32% in pCR-low; odds ratio=9.3, P = 0.001) independently of the rest of variables.”

Dr. Hoskins said the new report suggests that the assay can change treatment decisions, although he cautioned that “this study does not in itself establish its place in standard of care.” Large, prospective, randomized research is still needed, he said.

Dr. Martínez-Sáez said, in an interview, that the HER2DX assay should cost about as much as genomic assays for other breast cancer subtypes. These kinds of tests have cost several thousand dollars each in recent years.

What’s next? The decision impact study is ongoing. As for research into the assay itself, “prospective clinical trials are planned to demonstrate its clinical utility to de-escalate and guide therapy,” Dr. Martínez-Sáez said.

No funding is reported. Reveal Genomics is the developer of the HER2DX assay. Dr. Martinez- Saez reports financial relationships with Novartis, Eisai, Roche, and Reveal Genomics. Other study authors report multiple disclosures. Dr. Hoskins discloses non-financial research support from Agendia, which makes the MammaPrint early-breast-cancer assay.

The results from a prognostic genomic assay called HER2DX convinced a group of Spanish oncologists to change treatment plans for 56% of 89 patients with HER2-positive (HER2+) early breast cancer, according to new research.

The prospective pilot study is small, and the researchers didn’t report on how the patients fared, according to a poster presented at the European Society for Medical Oncology (ESMO) Breast Cancer annual congress. Plus, the test itself hasn’t been analyzed prospectively. But the study’s lead author, Olga Martínez-Sáez, MD, PhD, said in an interview that the 56% number is significant.

“We consider this percentage to be clinically very relevant,” said Dr. Martínez-Sáez, an oncologist at Hospital Clinic of Barcelona and the University of Barcelona. “HER2DX can change practice.”

Also in an interview, Kent Hoskins, MD, associate chief of hematology/oncology at University of Illinois at Chicago, described HER2DX as a next-generation genomic test that builds on assays developed 2 decades ago to help identify patients who would benefit – or not – from adjuvant chemotherapy.

Dr. Hoskins, who isn’t connected to the new study but has studied genomic tests for breast cancer, said the HER2DX test seeks to provide guidance to oncologists about which of several treatments are most effective in treating patients with HER2+ breast cancer.

“The overall trend in the HER2+ space is escalating therapy, and the cure rates have improved quite substantially,” he said. “But do they all need that much therapy? That’s the clinical question that this assay is addressing.”

The assay examines clinical features and the expression of 4 gene signatures, Dr. Martínez-Sáez said. It provides a risk score estimating the likelihood of recurrence plus a score that estimates the likelihood of achieving pathological complete response (pCR) with trastuzumab-based neoadjuvant therapy and an ERBB2 mRNA score.

In a retrospective 2022 study published in eBioMedicine, researchers reported that the assay “predicts response following neoadjuvant letrozole in combination with dual HER2 blockade with trastuzumab and pertuzumab in early-stage HER2-positive/hormone receptor–positive breast cancer.”

In the 2022 study, researchers wrote that assay results and other scores “might help better tailor systemic therapy in this context and identify candidates for avoiding chemotherapy, a therapy associated with short- and long-term toxicities and impact in quality of life.”

For the new study, a decision-impact analysis, researchers tracked 89 patients with HER2+ breast cancer (median age = 53 years, range 30-79, and 52% postmenopausal), the poster says. Most had T1-2 tumors (87%), negative nodes (64%), grade 2 (56%) or 3 (41%) tumors, and ductal histology (87%). And most were hormone receptor positive (65%). Seventy-eight percent of patients received neoadjuvant therapy (NAT), and 22% underwent upfront surgery.

In 56% of cases, oncologists changed their treatment decisions after getting the results of the HER2DX assays. In 59% of these cases, oncologists de-escalated therapy; in 41%, they escalated therapy, opting for more intense chemotherapy 65% of the time, according to the poster.

Clinician confidence in their decisions improved in 67% of cases, the researchers reported in their poster. Among 56 patients treated with neoadjuvant therapy who could be evaluated, “HER2DX pCR score was significantly associated with pCR (81% in pCR-medium/high and 32% in pCR-low; odds ratio=9.3, P = 0.001) independently of the rest of variables.”

Dr. Hoskins said the new report suggests that the assay can change treatment decisions, although he cautioned that “this study does not in itself establish its place in standard of care.” Large, prospective, randomized research is still needed, he said.

Dr. Martínez-Sáez said, in an interview, that the HER2DX assay should cost about as much as genomic assays for other breast cancer subtypes. These kinds of tests have cost several thousand dollars each in recent years.

What’s next? The decision impact study is ongoing. As for research into the assay itself, “prospective clinical trials are planned to demonstrate its clinical utility to de-escalate and guide therapy,” Dr. Martínez-Sáez said.

No funding is reported. Reveal Genomics is the developer of the HER2DX assay. Dr. Martinez- Saez reports financial relationships with Novartis, Eisai, Roche, and Reveal Genomics. Other study authors report multiple disclosures. Dr. Hoskins discloses non-financial research support from Agendia, which makes the MammaPrint early-breast-cancer assay.

The results from a prognostic genomic assay called HER2DX convinced a group of Spanish oncologists to change treatment plans for 56% of 89 patients with HER2-positive (HER2+) early breast cancer, according to new research.

The prospective pilot study is small, and the researchers didn’t report on how the patients fared, according to a poster presented at the European Society for Medical Oncology (ESMO) Breast Cancer annual congress. Plus, the test itself hasn’t been analyzed prospectively. But the study’s lead author, Olga Martínez-Sáez, MD, PhD, said in an interview that the 56% number is significant.

“We consider this percentage to be clinically very relevant,” said Dr. Martínez-Sáez, an oncologist at Hospital Clinic of Barcelona and the University of Barcelona. “HER2DX can change practice.”

Also in an interview, Kent Hoskins, MD, associate chief of hematology/oncology at University of Illinois at Chicago, described HER2DX as a next-generation genomic test that builds on assays developed 2 decades ago to help identify patients who would benefit – or not – from adjuvant chemotherapy.

Dr. Hoskins, who isn’t connected to the new study but has studied genomic tests for breast cancer, said the HER2DX test seeks to provide guidance to oncologists about which of several treatments are most effective in treating patients with HER2+ breast cancer.

“The overall trend in the HER2+ space is escalating therapy, and the cure rates have improved quite substantially,” he said. “But do they all need that much therapy? That’s the clinical question that this assay is addressing.”

The assay examines clinical features and the expression of 4 gene signatures, Dr. Martínez-Sáez said. It provides a risk score estimating the likelihood of recurrence plus a score that estimates the likelihood of achieving pathological complete response (pCR) with trastuzumab-based neoadjuvant therapy and an ERBB2 mRNA score.

In a retrospective 2022 study published in eBioMedicine, researchers reported that the assay “predicts response following neoadjuvant letrozole in combination with dual HER2 blockade with trastuzumab and pertuzumab in early-stage HER2-positive/hormone receptor–positive breast cancer.”

In the 2022 study, researchers wrote that assay results and other scores “might help better tailor systemic therapy in this context and identify candidates for avoiding chemotherapy, a therapy associated with short- and long-term toxicities and impact in quality of life.”

For the new study, a decision-impact analysis, researchers tracked 89 patients with HER2+ breast cancer (median age = 53 years, range 30-79, and 52% postmenopausal), the poster says. Most had T1-2 tumors (87%), negative nodes (64%), grade 2 (56%) or 3 (41%) tumors, and ductal histology (87%). And most were hormone receptor positive (65%). Seventy-eight percent of patients received neoadjuvant therapy (NAT), and 22% underwent upfront surgery.

In 56% of cases, oncologists changed their treatment decisions after getting the results of the HER2DX assays. In 59% of these cases, oncologists de-escalated therapy; in 41%, they escalated therapy, opting for more intense chemotherapy 65% of the time, according to the poster.

Clinician confidence in their decisions improved in 67% of cases, the researchers reported in their poster. Among 56 patients treated with neoadjuvant therapy who could be evaluated, “HER2DX pCR score was significantly associated with pCR (81% in pCR-medium/high and 32% in pCR-low; odds ratio=9.3, P = 0.001) independently of the rest of variables.”

Dr. Hoskins said the new report suggests that the assay can change treatment decisions, although he cautioned that “this study does not in itself establish its place in standard of care.” Large, prospective, randomized research is still needed, he said.

Dr. Martínez-Sáez said, in an interview, that the HER2DX assay should cost about as much as genomic assays for other breast cancer subtypes. These kinds of tests have cost several thousand dollars each in recent years.

What’s next? The decision impact study is ongoing. As for research into the assay itself, “prospective clinical trials are planned to demonstrate its clinical utility to de-escalate and guide therapy,” Dr. Martínez-Sáez said.

No funding is reported. Reveal Genomics is the developer of the HER2DX assay. Dr. Martinez- Saez reports financial relationships with Novartis, Eisai, Roche, and Reveal Genomics. Other study authors report multiple disclosures. Dr. Hoskins discloses non-financial research support from Agendia, which makes the MammaPrint early-breast-cancer assay.

Adding neoadjuvant atezolizumab to chemotherapy was associated with a significantly improved response in patients with early-stage triple-negative breast cancer, based on final data from a randomized trial.

The IMpassion031 trial showed significant improvement in pathological complete response (pCR) with the addition of atezolizumab to chemotherapy, as well as an acceptable safety profile, said Carlos H. Barrios, MD, of the Latin American Cooperative Oncology Group, Oncoclinicas, in Porto Allegre, Brazil, at the European Society for Medical Oncology (ESMO) Breast Cancer annual congress. Those findings were published in the Lancet in 2020.

Heidi Splete/MDedge News

Dr. Barrios reported data from a final analysis of the IMpassion031 trial, with data on event-free survival (EFS), disease-free survival (DFS) and overall survival (OS) in the intent-to-treat (ITT) and PD-L1–positive populations.

In the study, patients with early triple-negative breast cancer (eTNBC) and a primary tumor greater than 2 cm were randomized to 840 mg of atezolizumab once every 2 weeks plus a neoadjuvant chemotherapy regimen of nab-paclitaxel 125 mg/m² once weekly for 12 weeks, followed by doxorubicin 60 mg/m2 plus cyclophosphamide 600 mg/m² once every 2 weeks for 8 weeks. A total of 333 patients were randomized (165 atezolizumab and 168 placebo). Patients were stratified by stage II versus stage III, and by status of PD-L1, a protein that can predict treatment response (PD-L1 less than 1% vs. 1% or higher).

The primary endpoints (previously reported) were pathological complete response (pCR) in the ITT and PD-L1 populations. After a median follow-up of 39 months, the pCR was 58% in patients treated with atezolizumab versus 41% in those treated with neoadjuvant chemotherapy alone (P = .0044) in the ITT population, Dr. Barrios said. The added benefit from atezolizumab occurred regardless of the status of PD-L1.

Dr. Barrios reported the secondary outcomes of EFS, DFS, and OS in the intent-to-treat and PD-L1–positive populations. “This is a descriptive analysis, with no statistical comparison,” he emphasized.

The 2-year data on EFS, DFS, and OS consistently favored atezolizumab across key clinical subgroups, Dr. Barrios said. In the ITT population, 2-year EFS, DFS, and OS was 85%, 87%, and 95%, respectively, in the atezolizumab group and 80%, 83%, and 90%, respectively, in the placebo group. The results were similar, irrespective of PD-L1 status.

In the PD-L1–positive population, 2-year EFS, DFS, and OS was 89%, 91%, and 95%, respectively, in atezolizumab patients and 80%, 87%, and 91% in placebo patients.

Among patients without pCR at the time of surgery, 14 of 70 patients (20%) in the atezolizumab group and 33 of 99 patients (33%) in the placebo group received additional adjuvant systemic therapy. The most common adjunctive therapy was capecitabine.

As for safety, no new safety signals or treatment-related deaths were observed in the study. Overall, 70% of atezolizumab patients and 62% of placebo patients experienced grade 3 or 4 adverse events (AEs); 59% and 54% of which were treatment related. A total of 1% of patients in each group experienced grade 5 AEs. A total of 25% of atezolizumab patients and 20% of placebo patients experienced AEs leading to treatment discontinuation.

In a further exploratory analysis, pCR was highly predictive of long-term outcomes. Exploratory analysis of circulating tumor DNA (ctDNA) showed clearance in 89% of atezolizumab patients and 86% of placebo patients by the time of surgery.

Looking at the relationship between ctDNA, DFS, and OS, positive ctDNA was associated with a worse prognosis following surgery. As demonstrated in previous studies, pCR patients with negative ctDNA had the best DFS and OS. “In non-pCR patients with positive ctDNA, a numerical trend suggests improved overall survival with atezolizumab,” although the caveat is the very small numbers, Dr. Barrios said.

More research is needed, but in the final analysis, the significant pCR benefit seen with the addition of atezolizumab to chemotherapy for eTNBC translated into numerically improved EFS, DFS and OS, said Dr. Barrios. Additionally, “we should further analyze ctDNA to help select patients for further therapy.”

In a question-and-answer session, Dr. Barrios was asked how the results compared with other studies.

“We should not overinterpret the results,” he said. However, “what the IMpassion031 study shows is consistency; the results are aligned with previous studies addressing the same question of introducing immunotherapy,” in the patient population. Although the numbers in the IMpassion031 study did not reach statistical significance, it is important to recognize that they reflect previous research.

“In my opinion, looking at the whole field, immunotherapy is something we need to consider as part of the treatment of these patients,” said Dr. Barrios. However, more research is needed to better identify which patients do and do not need chemotherapy.
 

Phase 2 data show increased response with added atezolizumab for PD-L1–negative patients

In a second study known as ABSCG-52/ATHENE, researchers evaluated neoadjuvant atezolizumab in combination with dual HER2 blockade plus epirubicin for the treatment of patients with early HER2-positive breast cancer.

Heidi Splete/MDedge News

For most of these patients, the current standard of care is neoadjuvant dual HER2 blockade with trastuzumab (T) and pertuzumab (P) plus poly-chemotherapy, said Gabriel Rinnerthaler, MD, of the Salzburg (Austria) Cancer Research Institute, said in his presentation at the meeting. However, de-escalation of chemotherapy has been a major focus of research in recent years, and more research is needed on a combination of anthracyclines, such as epirubicin and idarubicin, and immune-checkpoint modulators.

In the phase 2 study, the researchers randomized patients with previously untreated, histologically confirmed HER2-positive early breast cancer (defined as a clinical prognostic stage cT1c–4a-d, N0-3, M0) in a 1:1 ratio to two 3-weekly cycles of a chemotherapy-free induction phase (part 1) with TP plus 1,200 mg atezolizumab (TP-A) or TP alone.

“We hypothesized that the additive effect of immune checkpoint inhibitors plus anti-HER2 therapy and chemotherapy would not be linear,” he said.

At the end of this period, all patients underwent four cycles of TP-A in combination with epirubicin (part 2). The primary endpoint was pCR (defined as absence of invasive cancer in the breast and axillary nodes, or ypT0/Tis ypN0) in the overall study population, and a pCR of 40% was considered a positive result.

A total of 29 patients were randomized to TP-A and 29 to TP alone in nine treatment centers in Austria. The study population ranged from 33 to 82 years, with a median age of 57 years. Most patients (72.4%) had hormone receptor (HR)–positive tumors; a total of 45 patients had stage IIA cancer, and 13 had stage IIB.

The primary endpoint of pCR occurred in 35 patients overall (60.3%). In a univariate analysis, the response rates were lower in HR-positive patients, in premenopausal patients, and in histologies other than NST (invasive carcinoma of no special type), Dr. Rinnerthaler said, but none of the differences were statistically significant, likely because of the small numbers in each group.

In an exploratory analysis of the ITT population with available PD-L1 data, the pCR was 69.2% for PD-L1–negative patients and 55.2% for PD-L1–positive patients.

“We observed the highest pCR rates in PD-L1–negative patients treated in the TP-A group and the lowest in PD-L1–positive patients treated with TP alone,” Dr. Rinnerthaler said.

No new safety concerns were observed during the study, Dr. Rinnerthaler noted. AEs of grade 3 or higher occurred in 17 patients (29.3%), including 9 in the TP-A group and 8 in the TP group. The most common AEs in both groups were nausea, diarrhea, and fatigue. No AEs of special interest of grade 3 or higher (defined as immune-related AEs, cardiac disorders, or infusion-related reactions) were observed.

The study findings were limited by the small sample size, but the resulting pCR rate of 60.3% was higher than the predefined threshold of 40% and supports additional research, said Dr. Rinnerthaler.

“For HER2-positive early breast cancer, a neoadjuvant chemotherapy de-escalation immunotherapy regimen with trastuzumab, pertuzumab, atezolizumab, and epirubicin is highly effective and safe and merits further investigation,” he concluded.

During a question-and-answer session, Dr. Rinnerthaler was asked why pCR increased in PD-L1 negative patients.

Previous data have shown that PD-L1 is up-regulated in certain tumors, and may serve as a surrogate for sensitivity, he said. In previous studies the additional effect of atezolizumab was seen in a PD-L1–negative group.

Dr. Rinnerthaler said he hopes to clarify this question when his research team reviews biopsy data from baseline and after the induction phase.
 

Defining response is key to de-escalation

In the IMpassion031 trial, “what we saw is a tendency to better outcomes for those patients who received atezolizumab,” said Matteo Lambertini, MD, of the University of Genova (Italy), who served as discussant for the two studies. The IMpassion031 study raises the question of where we are in the use of immuno-oncology for eTNBC. The study is now one of five neoadjuvant trials in this population.

Heidi Splete/MDedge News

Dr. Lambertini cited the KEYNOTE-522 study, which showed significant results in EFS. However, sample sizes and statistical design were different between these studies. “I think we need large studies of data in the adjuvant and postneoadjuvant setting for patients with triple-negative breast cancer.”

Postneoadjuvant considerations from the IMpassion031 trial showed good outcomes with no additional benefit of an immune checkpoint inhibitors.

For those patients with a pCR, it is definitely time to de-escalate treatment,” he said. In patients without pCR, escalation is needed, but an improved definition of pCR is also needed.

With regard to the ATHENE study, “it may be considered a positive study because the threshold of 40% was reached,” he said. The question is what is the optimum chemotherapy backbone. There appears to be no added benefit to adding an immune checkpoint inhibitor.

There are needs for defining the role of immunotherapy in HER2-positive breast cancer and more biomarker research to inform patient selection and study design, he said.

Finally, “I am not sure that the addition of an immune checkpoint inhibitor can be considered a de-escalation,” he noted.

IMpassion031 was supported by F. Hoffmann–La Roche. Dr. Barrio disclosed financial relationships with numerous companies. ABSCG-52/ATHENE was supported by the Austrian Breast and Colorectal Cancer Study Group and Roche Austria. Dr. Rinnerthaler disclosed relationships with multiple companies including Amgen, Daiichi Sankyo, Lilly, Gilead, MSD, Novartis, Pfizer, Roche, Seagen, and Pierre Fabre. Dr. Lambertini disclosed relationships with multiple companies including Roche, Novartis, AstraZeneca, Lilly, Exact Sciences, Pfizer, MSD, Seagen, Gilead, Takeda, Sandoz, Ipsen, Libbs, Knight, and Daiichi Sankyo.

Adding neoadjuvant atezolizumab to chemotherapy was associated with a significantly improved response in patients with early-stage triple-negative breast cancer, based on final data from a randomized trial.

The IMpassion031 trial showed significant improvement in pathological complete response (pCR) with the addition of atezolizumab to chemotherapy, as well as an acceptable safety profile, said Carlos H. Barrios, MD, of the Latin American Cooperative Oncology Group, Oncoclinicas, in Porto Allegre, Brazil, at the European Society for Medical Oncology (ESMO) Breast Cancer annual congress. Those findings were published in the Lancet in 2020.

Heidi Splete/MDedge News

Dr. Barrios reported data from a final analysis of the IMpassion031 trial, with data on event-free survival (EFS), disease-free survival (DFS) and overall survival (OS) in the intent-to-treat (ITT) and PD-L1–positive populations.

In the study, patients with early triple-negative breast cancer (eTNBC) and a primary tumor greater than 2 cm were randomized to 840 mg of atezolizumab once every 2 weeks plus a neoadjuvant chemotherapy regimen of nab-paclitaxel 125 mg/m² once weekly for 12 weeks, followed by doxorubicin 60 mg/m2 plus cyclophosphamide 600 mg/m² once every 2 weeks for 8 weeks. A total of 333 patients were randomized (165 atezolizumab and 168 placebo). Patients were stratified by stage II versus stage III, and by status of PD-L1, a protein that can predict treatment response (PD-L1 less than 1% vs. 1% or higher).

The primary endpoints (previously reported) were pathological complete response (pCR) in the ITT and PD-L1 populations. After a median follow-up of 39 months, the pCR was 58% in patients treated with atezolizumab versus 41% in those treated with neoadjuvant chemotherapy alone (P = .0044) in the ITT population, Dr. Barrios said. The added benefit from atezolizumab occurred regardless of the status of PD-L1.

Dr. Barrios reported the secondary outcomes of EFS, DFS, and OS in the intent-to-treat and PD-L1–positive populations. “This is a descriptive analysis, with no statistical comparison,” he emphasized.

The 2-year data on EFS, DFS, and OS consistently favored atezolizumab across key clinical subgroups, Dr. Barrios said. In the ITT population, 2-year EFS, DFS, and OS was 85%, 87%, and 95%, respectively, in the atezolizumab group and 80%, 83%, and 90%, respectively, in the placebo group. The results were similar, irrespective of PD-L1 status.

In the PD-L1–positive population, 2-year EFS, DFS, and OS was 89%, 91%, and 95%, respectively, in atezolizumab patients and 80%, 87%, and 91% in placebo patients.

Among patients without pCR at the time of surgery, 14 of 70 patients (20%) in the atezolizumab group and 33 of 99 patients (33%) in the placebo group received additional adjuvant systemic therapy. The most common adjunctive therapy was capecitabine.

As for safety, no new safety signals or treatment-related deaths were observed in the study. Overall, 70% of atezolizumab patients and 62% of placebo patients experienced grade 3 or 4 adverse events (AEs); 59% and 54% of which were treatment related. A total of 1% of patients in each group experienced grade 5 AEs. A total of 25% of atezolizumab patients and 20% of placebo patients experienced AEs leading to treatment discontinuation.

In a further exploratory analysis, pCR was highly predictive of long-term outcomes. Exploratory analysis of circulating tumor DNA (ctDNA) showed clearance in 89% of atezolizumab patients and 86% of placebo patients by the time of surgery.

Looking at the relationship between ctDNA, DFS, and OS, positive ctDNA was associated with a worse prognosis following surgery. As demonstrated in previous studies, pCR patients with negative ctDNA had the best DFS and OS. “In non-pCR patients with positive ctDNA, a numerical trend suggests improved overall survival with atezolizumab,” although the caveat is the very small numbers, Dr. Barrios said.

More research is needed, but in the final analysis, the significant pCR benefit seen with the addition of atezolizumab to chemotherapy for eTNBC translated into numerically improved EFS, DFS and OS, said Dr. Barrios. Additionally, “we should further analyze ctDNA to help select patients for further therapy.”

In a question-and-answer session, Dr. Barrios was asked how the results compared with other studies.

“We should not overinterpret the results,” he said. However, “what the IMpassion031 study shows is consistency; the results are aligned with previous studies addressing the same question of introducing immunotherapy,” in the patient population. Although the numbers in the IMpassion031 study did not reach statistical significance, it is important to recognize that they reflect previous research.

“In my opinion, looking at the whole field, immunotherapy is something we need to consider as part of the treatment of these patients,” said Dr. Barrios. However, more research is needed to better identify which patients do and do not need chemotherapy.
 

Phase 2 data show increased response with added atezolizumab for PD-L1–negative patients

In a second study known as ABSCG-52/ATHENE, researchers evaluated neoadjuvant atezolizumab in combination with dual HER2 blockade plus epirubicin for the treatment of patients with early HER2-positive breast cancer.

Heidi Splete/MDedge News

For most of these patients, the current standard of care is neoadjuvant dual HER2 blockade with trastuzumab (T) and pertuzumab (P) plus poly-chemotherapy, said Gabriel Rinnerthaler, MD, of the Salzburg (Austria) Cancer Research Institute, said in his presentation at the meeting. However, de-escalation of chemotherapy has been a major focus of research in recent years, and more research is needed on a combination of anthracyclines, such as epirubicin and idarubicin, and immune-checkpoint modulators.

In the phase 2 study, the researchers randomized patients with previously untreated, histologically confirmed HER2-positive early breast cancer (defined as a clinical prognostic stage cT1c–4a-d, N0-3, M0) in a 1:1 ratio to two 3-weekly cycles of a chemotherapy-free induction phase (part 1) with TP plus 1,200 mg atezolizumab (TP-A) or TP alone.

“We hypothesized that the additive effect of immune checkpoint inhibitors plus anti-HER2 therapy and chemotherapy would not be linear,” he said.

At the end of this period, all patients underwent four cycles of TP-A in combination with epirubicin (part 2). The primary endpoint was pCR (defined as absence of invasive cancer in the breast and axillary nodes, or ypT0/Tis ypN0) in the overall study population, and a pCR of 40% was considered a positive result.

A total of 29 patients were randomized to TP-A and 29 to TP alone in nine treatment centers in Austria. The study population ranged from 33 to 82 years, with a median age of 57 years. Most patients (72.4%) had hormone receptor (HR)–positive tumors; a total of 45 patients had stage IIA cancer, and 13 had stage IIB.

The primary endpoint of pCR occurred in 35 patients overall (60.3%). In a univariate analysis, the response rates were lower in HR-positive patients, in premenopausal patients, and in histologies other than NST (invasive carcinoma of no special type), Dr. Rinnerthaler said, but none of the differences were statistically significant, likely because of the small numbers in each group.

In an exploratory analysis of the ITT population with available PD-L1 data, the pCR was 69.2% for PD-L1–negative patients and 55.2% for PD-L1–positive patients.

“We observed the highest pCR rates in PD-L1–negative patients treated in the TP-A group and the lowest in PD-L1–positive patients treated with TP alone,” Dr. Rinnerthaler said.

No new safety concerns were observed during the study, Dr. Rinnerthaler noted. AEs of grade 3 or higher occurred in 17 patients (29.3%), including 9 in the TP-A group and 8 in the TP group. The most common AEs in both groups were nausea, diarrhea, and fatigue. No AEs of special interest of grade 3 or higher (defined as immune-related AEs, cardiac disorders, or infusion-related reactions) were observed.

The study findings were limited by the small sample size, but the resulting pCR rate of 60.3% was higher than the predefined threshold of 40% and supports additional research, said Dr. Rinnerthaler.

“For HER2-positive early breast cancer, a neoadjuvant chemotherapy de-escalation immunotherapy regimen with trastuzumab, pertuzumab, atezolizumab, and epirubicin is highly effective and safe and merits further investigation,” he concluded.

During a question-and-answer session, Dr. Rinnerthaler was asked why pCR increased in PD-L1 negative patients.

Previous data have shown that PD-L1 is up-regulated in certain tumors, and may serve as a surrogate for sensitivity, he said. In previous studies the additional effect of atezolizumab was seen in a PD-L1–negative group.

Dr. Rinnerthaler said he hopes to clarify this question when his research team reviews biopsy data from baseline and after the induction phase.
 

Defining response is key to de-escalation

In the IMpassion031 trial, “what we saw is a tendency to better outcomes for those patients who received atezolizumab,” said Matteo Lambertini, MD, of the University of Genova (Italy), who served as discussant for the two studies. The IMpassion031 study raises the question of where we are in the use of immuno-oncology for eTNBC. The study is now one of five neoadjuvant trials in this population.

Heidi Splete/MDedge News

Dr. Lambertini cited the KEYNOTE-522 study, which showed significant results in EFS. However, sample sizes and statistical design were different between these studies. “I think we need large studies of data in the adjuvant and postneoadjuvant setting for patients with triple-negative breast cancer.”

Postneoadjuvant considerations from the IMpassion031 trial showed good outcomes with no additional benefit of an immune checkpoint inhibitors.

For those patients with a pCR, it is definitely time to de-escalate treatment,” he said. In patients without pCR, escalation is needed, but an improved definition of pCR is also needed.

With regard to the ATHENE study, “it may be considered a positive study because the threshold of 40% was reached,” he said. The question is what is the optimum chemotherapy backbone. There appears to be no added benefit to adding an immune checkpoint inhibitor.

There are needs for defining the role of immunotherapy in HER2-positive breast cancer and more biomarker research to inform patient selection and study design, he said.

Finally, “I am not sure that the addition of an immune checkpoint inhibitor can be considered a de-escalation,” he noted.

IMpassion031 was supported by F. Hoffmann–La Roche. Dr. Barrio disclosed financial relationships with numerous companies. ABSCG-52/ATHENE was supported by the Austrian Breast and Colorectal Cancer Study Group and Roche Austria. Dr. Rinnerthaler disclosed relationships with multiple companies including Amgen, Daiichi Sankyo, Lilly, Gilead, MSD, Novartis, Pfizer, Roche, Seagen, and Pierre Fabre. Dr. Lambertini disclosed relationships with multiple companies including Roche, Novartis, AstraZeneca, Lilly, Exact Sciences, Pfizer, MSD, Seagen, Gilead, Takeda, Sandoz, Ipsen, Libbs, Knight, and Daiichi Sankyo.

Adding neoadjuvant atezolizumab to chemotherapy was associated with a significantly improved response in patients with early-stage triple-negative breast cancer, based on final data from a randomized trial.

The IMpassion031 trial showed significant improvement in pathological complete response (pCR) with the addition of atezolizumab to chemotherapy, as well as an acceptable safety profile, said Carlos H. Barrios, MD, of the Latin American Cooperative Oncology Group, Oncoclinicas, in Porto Allegre, Brazil, at the European Society for Medical Oncology (ESMO) Breast Cancer annual congress. Those findings were published in the Lancet in 2020.

Heidi Splete/MDedge News

Dr. Barrios reported data from a final analysis of the IMpassion031 trial, with data on event-free survival (EFS), disease-free survival (DFS) and overall survival (OS) in the intent-to-treat (ITT) and PD-L1–positive populations.

In the study, patients with early triple-negative breast cancer (eTNBC) and a primary tumor greater than 2 cm were randomized to 840 mg of atezolizumab once every 2 weeks plus a neoadjuvant chemotherapy regimen of nab-paclitaxel 125 mg/m² once weekly for 12 weeks, followed by doxorubicin 60 mg/m2 plus cyclophosphamide 600 mg/m² once every 2 weeks for 8 weeks. A total of 333 patients were randomized (165 atezolizumab and 168 placebo). Patients were stratified by stage II versus stage III, and by status of PD-L1, a protein that can predict treatment response (PD-L1 less than 1% vs. 1% or higher).

The primary endpoints (previously reported) were pathological complete response (pCR) in the ITT and PD-L1 populations. After a median follow-up of 39 months, the pCR was 58% in patients treated with atezolizumab versus 41% in those treated with neoadjuvant chemotherapy alone (P = .0044) in the ITT population, Dr. Barrios said. The added benefit from atezolizumab occurred regardless of the status of PD-L1.

Dr. Barrios reported the secondary outcomes of EFS, DFS, and OS in the intent-to-treat and PD-L1–positive populations. “This is a descriptive analysis, with no statistical comparison,” he emphasized.

The 2-year data on EFS, DFS, and OS consistently favored atezolizumab across key clinical subgroups, Dr. Barrios said. In the ITT population, 2-year EFS, DFS, and OS was 85%, 87%, and 95%, respectively, in the atezolizumab group and 80%, 83%, and 90%, respectively, in the placebo group. The results were similar, irrespective of PD-L1 status.

In the PD-L1–positive population, 2-year EFS, DFS, and OS was 89%, 91%, and 95%, respectively, in atezolizumab patients and 80%, 87%, and 91% in placebo patients.

Among patients without pCR at the time of surgery, 14 of 70 patients (20%) in the atezolizumab group and 33 of 99 patients (33%) in the placebo group received additional adjuvant systemic therapy. The most common adjunctive therapy was capecitabine.

As for safety, no new safety signals or treatment-related deaths were observed in the study. Overall, 70% of atezolizumab patients and 62% of placebo patients experienced grade 3 or 4 adverse events (AEs); 59% and 54% of which were treatment related. A total of 1% of patients in each group experienced grade 5 AEs. A total of 25% of atezolizumab patients and 20% of placebo patients experienced AEs leading to treatment discontinuation.

In a further exploratory analysis, pCR was highly predictive of long-term outcomes. Exploratory analysis of circulating tumor DNA (ctDNA) showed clearance in 89% of atezolizumab patients and 86% of placebo patients by the time of surgery.

Looking at the relationship between ctDNA, DFS, and OS, positive ctDNA was associated with a worse prognosis following surgery. As demonstrated in previous studies, pCR patients with negative ctDNA had the best DFS and OS. “In non-pCR patients with positive ctDNA, a numerical trend suggests improved overall survival with atezolizumab,” although the caveat is the very small numbers, Dr. Barrios said.

More research is needed, but in the final analysis, the significant pCR benefit seen with the addition of atezolizumab to chemotherapy for eTNBC translated into numerically improved EFS, DFS and OS, said Dr. Barrios. Additionally, “we should further analyze ctDNA to help select patients for further therapy.”

In a question-and-answer session, Dr. Barrios was asked how the results compared with other studies.

“We should not overinterpret the results,” he said. However, “what the IMpassion031 study shows is consistency; the results are aligned with previous studies addressing the same question of introducing immunotherapy,” in the patient population. Although the numbers in the IMpassion031 study did not reach statistical significance, it is important to recognize that they reflect previous research.

“In my opinion, looking at the whole field, immunotherapy is something we need to consider as part of the treatment of these patients,” said Dr. Barrios. However, more research is needed to better identify which patients do and do not need chemotherapy.
 

Phase 2 data show increased response with added atezolizumab for PD-L1–negative patients

In a second study known as ABSCG-52/ATHENE, researchers evaluated neoadjuvant atezolizumab in combination with dual HER2 blockade plus epirubicin for the treatment of patients with early HER2-positive breast cancer.

Heidi Splete/MDedge News

For most of these patients, the current standard of care is neoadjuvant dual HER2 blockade with trastuzumab (T) and pertuzumab (P) plus poly-chemotherapy, said Gabriel Rinnerthaler, MD, of the Salzburg (Austria) Cancer Research Institute, said in his presentation at the meeting. However, de-escalation of chemotherapy has been a major focus of research in recent years, and more research is needed on a combination of anthracyclines, such as epirubicin and idarubicin, and immune-checkpoint modulators.

In the phase 2 study, the researchers randomized patients with previously untreated, histologically confirmed HER2-positive early breast cancer (defined as a clinical prognostic stage cT1c–4a-d, N0-3, M0) in a 1:1 ratio to two 3-weekly cycles of a chemotherapy-free induction phase (part 1) with TP plus 1,200 mg atezolizumab (TP-A) or TP alone.

“We hypothesized that the additive effect of immune checkpoint inhibitors plus anti-HER2 therapy and chemotherapy would not be linear,” he said.

At the end of this period, all patients underwent four cycles of TP-A in combination with epirubicin (part 2). The primary endpoint was pCR (defined as absence of invasive cancer in the breast and axillary nodes, or ypT0/Tis ypN0) in the overall study population, and a pCR of 40% was considered a positive result.

A total of 29 patients were randomized to TP-A and 29 to TP alone in nine treatment centers in Austria. The study population ranged from 33 to 82 years, with a median age of 57 years. Most patients (72.4%) had hormone receptor (HR)–positive tumors; a total of 45 patients had stage IIA cancer, and 13 had stage IIB.

The primary endpoint of pCR occurred in 35 patients overall (60.3%). In a univariate analysis, the response rates were lower in HR-positive patients, in premenopausal patients, and in histologies other than NST (invasive carcinoma of no special type), Dr. Rinnerthaler said, but none of the differences were statistically significant, likely because of the small numbers in each group.

In an exploratory analysis of the ITT population with available PD-L1 data, the pCR was 69.2% for PD-L1–negative patients and 55.2% for PD-L1–positive patients.

“We observed the highest pCR rates in PD-L1–negative patients treated in the TP-A group and the lowest in PD-L1–positive patients treated with TP alone,” Dr. Rinnerthaler said.

No new safety concerns were observed during the study, Dr. Rinnerthaler noted. AEs of grade 3 or higher occurred in 17 patients (29.3%), including 9 in the TP-A group and 8 in the TP group. The most common AEs in both groups were nausea, diarrhea, and fatigue. No AEs of special interest of grade 3 or higher (defined as immune-related AEs, cardiac disorders, or infusion-related reactions) were observed.

The study findings were limited by the small sample size, but the resulting pCR rate of 60.3% was higher than the predefined threshold of 40% and supports additional research, said Dr. Rinnerthaler.

“For HER2-positive early breast cancer, a neoadjuvant chemotherapy de-escalation immunotherapy regimen with trastuzumab, pertuzumab, atezolizumab, and epirubicin is highly effective and safe and merits further investigation,” he concluded.

During a question-and-answer session, Dr. Rinnerthaler was asked why pCR increased in PD-L1 negative patients.

Previous data have shown that PD-L1 is up-regulated in certain tumors, and may serve as a surrogate for sensitivity, he said. In previous studies the additional effect of atezolizumab was seen in a PD-L1–negative group.

Dr. Rinnerthaler said he hopes to clarify this question when his research team reviews biopsy data from baseline and after the induction phase.
 

Defining response is key to de-escalation

In the IMpassion031 trial, “what we saw is a tendency to better outcomes for those patients who received atezolizumab,” said Matteo Lambertini, MD, of the University of Genova (Italy), who served as discussant for the two studies. The IMpassion031 study raises the question of where we are in the use of immuno-oncology for eTNBC. The study is now one of five neoadjuvant trials in this population.

Heidi Splete/MDedge News

Dr. Lambertini cited the KEYNOTE-522 study, which showed significant results in EFS. However, sample sizes and statistical design were different between these studies. “I think we need large studies of data in the adjuvant and postneoadjuvant setting for patients with triple-negative breast cancer.”

Postneoadjuvant considerations from the IMpassion031 trial showed good outcomes with no additional benefit of an immune checkpoint inhibitors.

For those patients with a pCR, it is definitely time to de-escalate treatment,” he said. In patients without pCR, escalation is needed, but an improved definition of pCR is also needed.

With regard to the ATHENE study, “it may be considered a positive study because the threshold of 40% was reached,” he said. The question is what is the optimum chemotherapy backbone. There appears to be no added benefit to adding an immune checkpoint inhibitor.

There are needs for defining the role of immunotherapy in HER2-positive breast cancer and more biomarker research to inform patient selection and study design, he said.

Finally, “I am not sure that the addition of an immune checkpoint inhibitor can be considered a de-escalation,” he noted.

IMpassion031 was supported by F. Hoffmann–La Roche. Dr. Barrio disclosed financial relationships with numerous companies. ABSCG-52/ATHENE was supported by the Austrian Breast and Colorectal Cancer Study Group and Roche Austria. Dr. Rinnerthaler disclosed relationships with multiple companies including Amgen, Daiichi Sankyo, Lilly, Gilead, MSD, Novartis, Pfizer, Roche, Seagen, and Pierre Fabre. Dr. Lambertini disclosed relationships with multiple companies including Roche, Novartis, AstraZeneca, Lilly, Exact Sciences, Pfizer, MSD, Seagen, Gilead, Takeda, Sandoz, Ipsen, Libbs, Knight, and Daiichi Sankyo.

Bariatric surgery for obesity is associated with a reduced risk of developing breast cancer, new data suggest.

In a matched cohort study of more than 69,000 Canadian women, risk for incident breast cancer at 1 year was 40% higher among women who had not undergone bariatric surgery, compared with those who had. The risk remained elevated through 5 years of follow-up.

The findings were “definitely a bit surprising,” study author Aristithes G. Doumouras, MD, MPH, assistant professor of surgery at McMaster University, Hamilton, Ont., said in an interview. “The patients that underwent bariatric surgery had better cancer outcomes than patients who weighed less than they did, so it showed that there was more at play than just weight loss. This effect was durable [and] shows how powerful the surgery is, [as well as] the fact that we haven’t even explored all of its effects.”

The study was published online in JAMA Surgery.
 

Protective association

To determine whether there is a residual risk for breast cancer following bariatric surgery for obesity, the investigators analyzed clinical and administrative data collected between 2010 and 2016 in Ontario. They retrospectively matched women with obesity who underwent bariatric surgery with women without a history of bariatric surgery. Participants were matched by age and breast cancer screening status. Covariates included diabetes status, neighborhood income quintile, and measures of health care use. The population included 69,260 women (mean age, 45 years).

Among participants who underwent bariatric surgery for obesity, baseline body mass index was greater than 35 for those with related comorbid conditions, and BMI was greater than 40 for those without comorbid conditions. The investigators categorized nonsurgical control patients in accordance with the following four BMI categories: less than 25, 25-29, 30-34, and greater than or equal to 35. Each control group, as well as the surgical group, included 13,852 women.

Participants in the surgical group were followed for 5 years after bariatric surgery. Those in the nonsurgical group were followed for 5 years after the index date (that is, the date of BMI measurement).

In the overall population, 659 cases of breast cancer were diagnosed in the overall population (0.95%) during the study period. This total included 103 (0.74%) cancers in the surgical cohort; 128 (0.92%) in the group with BMI less than 25; 143 (1.03%) among those with BMI 25-29; 150 (1.08%) in the group with BMI 30-34; and 135 (0.97%) among those with BMI greater than or equal to 35.

Most cancers were stage I. There were 65 cases among those with BMI less than 25; 76 for those with BMI of 25-29; 65 for BMI of 30-34; 67 for BMI greater than or equal to 35, and 60 for the surgery group.

Most tumors were of medium grade and were estrogen receptor positive, progesterone receptor positive, and ERBB2 negative. No significant differences were observed across the groups for stage, grade, or hormone status.

There was an increased hazard for incident breast cancer in the nonsurgical group, compared with the postsurgical group after washout periods of 1 year (hazard ratio, 1.40), 2 years (HR, 1.31), and 5 years (HR, 1.38).

In a comparison of the postsurgical cohort with the nonsurgical cohort with BMI less than 25, the hazard of incident breast cancer was not significantly different for any of the washout periods, but there was a reduced hazard for incident breast cancer among postsurgical patients than among nonsurgical patients in all high BMI categories (BMI ≥ 25).

“Taken together, these results demonstrate that the protective association between substantial weight loss via bariatric surgery and breast cancer risk is sustained after 5 years following surgery and that it is associated with a baseline risk similar to that of women with BMI less than 25,” the investigators write.

Nevertheless, Dr. Doumouras said “the interaction between the surgery and individuals is poorly studied, and this level of personalized medicine is simply not there yet. We are working on developing a prospective cohort that has genetic, protein, and microbiome [data] to help answer these questions.”

There are not enough women in subpopulations such as BRCA carriers to study at this point, he added. “This is where more patients and time will really help the research process.”
 

A universal benefit?

“Although these findings are important overall for the general population at risk for breast cancer, we raise an important caveat: The benefit of surgical weight loss may not be universal,” write Justin B. Dimick, MD, MPH, surgical innovation editor for JAMA Surgery, and Melissa L. Pilewskie, MD, both of the University of Michigan, Ann Arbor, in an accompanying commentary.

“In addition to lifestyle factors, several nonmodifiable risk factors, such as a genetic predisposition, strong family history, personal history of a high-risk breast lesion, or history of chest wall radiation, impart significant elevation in risk, and the data remain mixed on the impact of weight loss for individuals in these high-risk cohorts,” they add.

“Further study to elucidate the underlying mechanism associated with obesity, weight loss, and breast cancer risk should help guide strategies for risk reduction that are specific to unique high-risk cohorts, because modifiable risk factors may not portend the same benefit among all groups.”

Commenting on the findings, Stephen Edge, MD, breast surgeon and vice president for system quality and outcomes at Roswell Park Comprehensive Cancer Center, Buffalo, N.Y., said, “The importance of this study is that it shows that weight loss in midlife can reduce breast cancer risk back to or even below the risk of similar people who were not obese. This has major implications for counseling women.”

The investigators did not have information on the extent of weight loss with surgery or on which participants maintained the lower weight, Dr. Edge noted; “However, overall, most people who have weight reduction surgery have major weight loss.”

At this point, he said, “we can now tell women with obesity that in addition to the many other advantages of weight loss, their risk of getting breast cancer will also be reduced.”

The study was supported by the Ontario Bariatric Registry and ICES, which is funded by an annual grant from the Ontario Ministry of Health and the Ontario Ministry of Long-Term Care. Dr. Doumouras, Dr. Dimick, Dr. Pilewskie, and Dr. Edge reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Bariatric surgery for obesity is associated with a reduced risk of developing breast cancer, new data suggest.

In a matched cohort study of more than 69,000 Canadian women, risk for incident breast cancer at 1 year was 40% higher among women who had not undergone bariatric surgery, compared with those who had. The risk remained elevated through 5 years of follow-up.

The findings were “definitely a bit surprising,” study author Aristithes G. Doumouras, MD, MPH, assistant professor of surgery at McMaster University, Hamilton, Ont., said in an interview. “The patients that underwent bariatric surgery had better cancer outcomes than patients who weighed less than they did, so it showed that there was more at play than just weight loss. This effect was durable [and] shows how powerful the surgery is, [as well as] the fact that we haven’t even explored all of its effects.”

The study was published online in JAMA Surgery.
 

Protective association

To determine whether there is a residual risk for breast cancer following bariatric surgery for obesity, the investigators analyzed clinical and administrative data collected between 2010 and 2016 in Ontario. They retrospectively matched women with obesity who underwent bariatric surgery with women without a history of bariatric surgery. Participants were matched by age and breast cancer screening status. Covariates included diabetes status, neighborhood income quintile, and measures of health care use. The population included 69,260 women (mean age, 45 years).

Among participants who underwent bariatric surgery for obesity, baseline body mass index was greater than 35 for those with related comorbid conditions, and BMI was greater than 40 for those without comorbid conditions. The investigators categorized nonsurgical control patients in accordance with the following four BMI categories: less than 25, 25-29, 30-34, and greater than or equal to 35. Each control group, as well as the surgical group, included 13,852 women.

Participants in the surgical group were followed for 5 years after bariatric surgery. Those in the nonsurgical group were followed for 5 years after the index date (that is, the date of BMI measurement).

In the overall population, 659 cases of breast cancer were diagnosed in the overall population (0.95%) during the study period. This total included 103 (0.74%) cancers in the surgical cohort; 128 (0.92%) in the group with BMI less than 25; 143 (1.03%) among those with BMI 25-29; 150 (1.08%) in the group with BMI 30-34; and 135 (0.97%) among those with BMI greater than or equal to 35.

Most cancers were stage I. There were 65 cases among those with BMI less than 25; 76 for those with BMI of 25-29; 65 for BMI of 30-34; 67 for BMI greater than or equal to 35, and 60 for the surgery group.

Most tumors were of medium grade and were estrogen receptor positive, progesterone receptor positive, and ERBB2 negative. No significant differences were observed across the groups for stage, grade, or hormone status.

There was an increased hazard for incident breast cancer in the nonsurgical group, compared with the postsurgical group after washout periods of 1 year (hazard ratio, 1.40), 2 years (HR, 1.31), and 5 years (HR, 1.38).

In a comparison of the postsurgical cohort with the nonsurgical cohort with BMI less than 25, the hazard of incident breast cancer was not significantly different for any of the washout periods, but there was a reduced hazard for incident breast cancer among postsurgical patients than among nonsurgical patients in all high BMI categories (BMI ≥ 25).

“Taken together, these results demonstrate that the protective association between substantial weight loss via bariatric surgery and breast cancer risk is sustained after 5 years following surgery and that it is associated with a baseline risk similar to that of women with BMI less than 25,” the investigators write.

Nevertheless, Dr. Doumouras said “the interaction between the surgery and individuals is poorly studied, and this level of personalized medicine is simply not there yet. We are working on developing a prospective cohort that has genetic, protein, and microbiome [data] to help answer these questions.”

There are not enough women in subpopulations such as BRCA carriers to study at this point, he added. “This is where more patients and time will really help the research process.”
 

A universal benefit?

“Although these findings are important overall for the general population at risk for breast cancer, we raise an important caveat: The benefit of surgical weight loss may not be universal,” write Justin B. Dimick, MD, MPH, surgical innovation editor for JAMA Surgery, and Melissa L. Pilewskie, MD, both of the University of Michigan, Ann Arbor, in an accompanying commentary.

“In addition to lifestyle factors, several nonmodifiable risk factors, such as a genetic predisposition, strong family history, personal history of a high-risk breast lesion, or history of chest wall radiation, impart significant elevation in risk, and the data remain mixed on the impact of weight loss for individuals in these high-risk cohorts,” they add.

“Further study to elucidate the underlying mechanism associated with obesity, weight loss, and breast cancer risk should help guide strategies for risk reduction that are specific to unique high-risk cohorts, because modifiable risk factors may not portend the same benefit among all groups.”

Commenting on the findings, Stephen Edge, MD, breast surgeon and vice president for system quality and outcomes at Roswell Park Comprehensive Cancer Center, Buffalo, N.Y., said, “The importance of this study is that it shows that weight loss in midlife can reduce breast cancer risk back to or even below the risk of similar people who were not obese. This has major implications for counseling women.”

The investigators did not have information on the extent of weight loss with surgery or on which participants maintained the lower weight, Dr. Edge noted; “However, overall, most people who have weight reduction surgery have major weight loss.”

At this point, he said, “we can now tell women with obesity that in addition to the many other advantages of weight loss, their risk of getting breast cancer will also be reduced.”

The study was supported by the Ontario Bariatric Registry and ICES, which is funded by an annual grant from the Ontario Ministry of Health and the Ontario Ministry of Long-Term Care. Dr. Doumouras, Dr. Dimick, Dr. Pilewskie, and Dr. Edge reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Bariatric surgery for obesity is associated with a reduced risk of developing breast cancer, new data suggest.

In a matched cohort study of more than 69,000 Canadian women, risk for incident breast cancer at 1 year was 40% higher among women who had not undergone bariatric surgery, compared with those who had. The risk remained elevated through 5 years of follow-up.

The findings were “definitely a bit surprising,” study author Aristithes G. Doumouras, MD, MPH, assistant professor of surgery at McMaster University, Hamilton, Ont., said in an interview. “The patients that underwent bariatric surgery had better cancer outcomes than patients who weighed less than they did, so it showed that there was more at play than just weight loss. This effect was durable [and] shows how powerful the surgery is, [as well as] the fact that we haven’t even explored all of its effects.”

The study was published online in JAMA Surgery.
 

Protective association

To determine whether there is a residual risk for breast cancer following bariatric surgery for obesity, the investigators analyzed clinical and administrative data collected between 2010 and 2016 in Ontario. They retrospectively matched women with obesity who underwent bariatric surgery with women without a history of bariatric surgery. Participants were matched by age and breast cancer screening status. Covariates included diabetes status, neighborhood income quintile, and measures of health care use. The population included 69,260 women (mean age, 45 years).

Among participants who underwent bariatric surgery for obesity, baseline body mass index was greater than 35 for those with related comorbid conditions, and BMI was greater than 40 for those without comorbid conditions. The investigators categorized nonsurgical control patients in accordance with the following four BMI categories: less than 25, 25-29, 30-34, and greater than or equal to 35. Each control group, as well as the surgical group, included 13,852 women.

Participants in the surgical group were followed for 5 years after bariatric surgery. Those in the nonsurgical group were followed for 5 years after the index date (that is, the date of BMI measurement).

In the overall population, 659 cases of breast cancer were diagnosed in the overall population (0.95%) during the study period. This total included 103 (0.74%) cancers in the surgical cohort; 128 (0.92%) in the group with BMI less than 25; 143 (1.03%) among those with BMI 25-29; 150 (1.08%) in the group with BMI 30-34; and 135 (0.97%) among those with BMI greater than or equal to 35.

Most cancers were stage I. There were 65 cases among those with BMI less than 25; 76 for those with BMI of 25-29; 65 for BMI of 30-34; 67 for BMI greater than or equal to 35, and 60 for the surgery group.

Most tumors were of medium grade and were estrogen receptor positive, progesterone receptor positive, and ERBB2 negative. No significant differences were observed across the groups for stage, grade, or hormone status.

There was an increased hazard for incident breast cancer in the nonsurgical group, compared with the postsurgical group after washout periods of 1 year (hazard ratio, 1.40), 2 years (HR, 1.31), and 5 years (HR, 1.38).

In a comparison of the postsurgical cohort with the nonsurgical cohort with BMI less than 25, the hazard of incident breast cancer was not significantly different for any of the washout periods, but there was a reduced hazard for incident breast cancer among postsurgical patients than among nonsurgical patients in all high BMI categories (BMI ≥ 25).

“Taken together, these results demonstrate that the protective association between substantial weight loss via bariatric surgery and breast cancer risk is sustained after 5 years following surgery and that it is associated with a baseline risk similar to that of women with BMI less than 25,” the investigators write.

Nevertheless, Dr. Doumouras said “the interaction between the surgery and individuals is poorly studied, and this level of personalized medicine is simply not there yet. We are working on developing a prospective cohort that has genetic, protein, and microbiome [data] to help answer these questions.”

There are not enough women in subpopulations such as BRCA carriers to study at this point, he added. “This is where more patients and time will really help the research process.”
 

A universal benefit?

“Although these findings are important overall for the general population at risk for breast cancer, we raise an important caveat: The benefit of surgical weight loss may not be universal,” write Justin B. Dimick, MD, MPH, surgical innovation editor for JAMA Surgery, and Melissa L. Pilewskie, MD, both of the University of Michigan, Ann Arbor, in an accompanying commentary.

“In addition to lifestyle factors, several nonmodifiable risk factors, such as a genetic predisposition, strong family history, personal history of a high-risk breast lesion, or history of chest wall radiation, impart significant elevation in risk, and the data remain mixed on the impact of weight loss for individuals in these high-risk cohorts,” they add.

“Further study to elucidate the underlying mechanism associated with obesity, weight loss, and breast cancer risk should help guide strategies for risk reduction that are specific to unique high-risk cohorts, because modifiable risk factors may not portend the same benefit among all groups.”

Commenting on the findings, Stephen Edge, MD, breast surgeon and vice president for system quality and outcomes at Roswell Park Comprehensive Cancer Center, Buffalo, N.Y., said, “The importance of this study is that it shows that weight loss in midlife can reduce breast cancer risk back to or even below the risk of similar people who were not obese. This has major implications for counseling women.”

The investigators did not have information on the extent of weight loss with surgery or on which participants maintained the lower weight, Dr. Edge noted; “However, overall, most people who have weight reduction surgery have major weight loss.”

At this point, he said, “we can now tell women with obesity that in addition to the many other advantages of weight loss, their risk of getting breast cancer will also be reduced.”

The study was supported by the Ontario Bariatric Registry and ICES, which is funded by an annual grant from the Ontario Ministry of Health and the Ontario Ministry of Long-Term Care. Dr. Doumouras, Dr. Dimick, Dr. Pilewskie, and Dr. Edge reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.