Lung cancer has been the leading cause of cancer-related mortality for decades. It is also predicted to remain as the leading cause of cancer-related mortality through 2030.1 Platinum-based chemotherapy, including carboplatin and paclitaxel, was introduced 3 decades ago and revolutionized the management of advanced non–small cell lung cancer (NSCLC). A more recent advancement has been mutant epidermal growth factor receptor–tyrosine kinase (EGFR-TK) inhibitors.1 EGFR is a transmembrane protein that functions by transducing essential growth factor signaling from the extracellular milieu to the cell. As 60% of the advanced NSCLC expresses this receptor, blocking the mutant EGFR receptor was a groundbreaking development in the management of advanced NSCLC.2 Development of mutant EGFR-TK inhibitors has revolutionized the management of advanced NSCLC. This study was conducted to determine the safety profile of mutant EGFR-TK inhibitors in the management of advanced NSCLC.
This meta-analysis was conducted according to Cochrane Collaboration guidelines and reported as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The findings are summarized in the PRISMA flow diagram (Figure 1). Two authors (MZ and MM) performed a systematic literature search using databases such as MEDLINE (via PubMed), Embase, and Cochrane Library using the medical search terms and their respective entry words with the following search strategy: safety, “mutant EGFR-TK inhibitors,” advanced, “non–small cell,” “lung cancer,” “adverse effect,” and literature. Additionally, unpublished trials were identified from clinicaltrials.gov, and references of all pertinent articles were also scrutinized to ensure the inclusion of all relevant studies. The search was completed on June 1, 2021, and we only included studies available in English. Two authors (MM and MZ) independently screened the search results in a 2-step process based on predetermined inclusion/exclusion criteria. First, 890 articles were evaluated for relevance on title and abstract level, followed by full-text screening of the final list of 140 articles. Any disagreements were resolved by discussion or third-party review, and a total of 9 articles were included in the study.
The following eligibility criteria were used: original articles reporting adverse effects (AEs) of mutant EGFR-TK inhibitors in patients with advanced NSCLC compared with control groups receiving platinum-based chemotherapy. All the patients included in the study had an EGFR mutation but randomly assigned to either treatment or control group. All articles with subjective data on mutant EGFR-TK inhibitors AEs in patients with advanced NSCLC compared with control groups receiving platinum-based chemotherapy were included in the analysis. Only 9 articles qualified the aforementioned selection criteria for eligibility. All qualifying studies were nationwide inpatient or pooled clinical trials data. The reasons for exclusion of the other 71 articles were irrelevant (n = 31), duplicate (n = 13), reviews (n = 14), and poor data reporting (n = 12). Out of the 9 included studies, 9 studies showed correlation of AEs, including rash, diarrhea, nausea, and fatigue. Seven studies showed correlation of AEs including neutropenia, anorexia, and vomiting. Six studies showed correlation of anemia, cough, and stomatitis. Five studies showed correlation of elevated aspartate aminotransferase (AST), alanine aminotransferase (ALT), and leucopenia. Four studies showed correlation of fever between mutant EGFR-TK inhibitors and platinum-based chemotherapy.
The primary endpoints were reported AEs including rash, diarrhea, elevated ALT, elevated AST, stomatitis, nausea, leucopenia, fatigue, neutropenia, anorexia, anemia, cough, vomiting, and fever, respectively. Data on baseline characteristics and clinical outcomes were then extracted, and summary tables were created. Summary estimates of the clinical endpoints were then calculated with risk ratio (RR) and 95% confidence intervals (CIs) using the random-effects model. Heterogeneity between studies was examined with the Cochran Q I2 statistic which can be defined as low (25% to 50%), moderate (50% to 75%), or high (> 75%). Statistical analysis was performed using Comprehensive Meta-Analysis Software CMA Version 3.0.
A total of 9 studies including 3415 patients (1775 in EGFR-TK inhibitor treatment group while 1640 patients in platinum-based chemotherapy control group) were included in the study. All 9 studies were phase III randomized control clinical trials conducted to compare the safety profile of mutant EGFR-TK inhibitors in patients with advanced NSCLC. Mean age was 61 years in both treatment and control groups. Further details on study and participant characteristics and safety profile including AEs are summarized in Tables 1 and 2. No evidence of publication bias was found.
Rash developed in 45.8% of patients in the treatment group receiving mutant EGFR-TK inhibitors vs only 5.6% of patients in the control group receiving platinum-based chemotherapy. Overall RR of 7.38 with the 95% CI noted, which was statistically significant, confirming higher rash event rates in patients receiving EGFR-TK inhibitors for their advanced NSCLC (Figure 2).
Diarrhea occurred in 33.6% of patients in the mutant EGFR-TK inhibitors treatment group vs 13.5% of patients in the control group receiving platinum-based chemotherapy. Overall RR of 2.63 and 95% CI was noted, which was statistically significant, confirming higher diarrheal rates in patients receiving EGFR-TK inhibitors for their advanced NSCLC (Figure 3).