Residents’ Corner

Current Controversies in Mohs Micrographic Surgery

Author and Disclosure Information



A current hot topic of controversy focuses on the wide variation among Mohs surgeons in the mean number of stages used to resect a tumor. Overuse among outliers has been proposed to stem from lack of technical expertise or from abuse of the current fee-for-service payment model, which bases compensation on the number of stages performed. A study by Krishnan et al10 determined that the mean number of stages per tumor in the studied population (all physicians [N=2305] receiving Medicare payments for MMS from January 2012 to December 2014) was 1.74, with a range of 1.09 to 4.11. Persistently high outliers were more likely to perform MMS in a solo practice, with an odds ratio of 2.35.10 In response to the wide variation in mean stages used to resect a skin cancer and its implications on increased financial burden and surgery to individual patients, intervention has been proposed. Notably, it has been demonstrated that mailing out individual reports of practice patterns to high-outlier physicians resulted in a reduction in mean stages per tumor as well as an associated cost savings when compared to outlier physicians who did not receive these reports.11

Controversies in Reimbursement

Mohs micrographic surgery also has been in the spotlight for debate regarding reimbursement. The procedure has been targeted partly in response to its substantial contribution to total Medicare reimbursements paid out. In 2013, primary MMS billing codes constituted nearly 19% of total reimbursements to dermatologists and approximately 0.5% of total reimbursements to all physicians participating in Medicare.12 Mohs micrographic surgery codes have correspondingly received frequent review by the Relative Value Scale Update Committee and remained on a list of potentially misvalued services according to the Centers for Medicare & Medicaid Services for years.13 Due to continued scrutiny and review, especially by the Relative Value Scale Update Committee and Centers for Medicare & Medicaid Services, reimbursement to perform MMS and reconstructive surgery has gone down by more than 20% in the last 15 years.14 Public perception mirrors third-party payer concerns for overcompensation. An article title in the New York Times theatrically postures “Patients’ Costs Skyrocket, Specialists’ Incomes Soar.” The article recounts an MMS patient’s “outrage at charges” associated with treatment of her “minor medical problem” and the simultaneous “sharp climb” in dermatologist income over the last 2 decades.15

However, studies continue to demonstrate the cost-effectiveness of MMS. A study by Ravitskiy et al16 demonstrates the cost-effectiveness of MMS, regardless of place of service or type of tumor. Of 406 tumors studied, MMS was the least expensive surgical procedure evaluated ($805 per tumor) when compared to standard surgical excision with permanent margins ($1026 per tumor), standard surgical excision with frozen margins ($1200 per tumor), and ambulatory surgery center standard surgical excision ($2507 per tumor). Furthermore, adjusted for inflation, the cost of MMS was lower in 2009 vs 1998.16 Similar results have been consistently demonstrated.17

Controversies in the AUC

To provide clinicians, policy makers, and insurers guidance for utilization of MMS in the setting of concerns for overutilization, overcompensation, and inappropriate application, the MMS AUC were established in 2012. The guidelines were developed by a process integrating evidence-based medicine, clinical experience, and expert opinion and is applicable to 270 clinical scenarios.18

Next Article: