Etzkorn, Jeremy R.

BACKGROUND The use of Mohs micrographic surgery as a treatment for melanoma is rising, but the reliability of Mohs surgeons in assessing MART-1 melanoma en-face margins has not been evaluated. OBJECTIVE To evaluate interrater and intrarater reliability of Mohs surgeons in interpreting margins of early-stage melanoma. METHODS Twenty Mohs surgeons were asked to independently review images of frozen section MART-1 en-face peripheral margins of in situ or early-stage melanoma. Surgeons determined margins as positive or negative at initial evaluation and 6 weeks later. Primary outcomes were interrater and intrarater reliability. RESULTS Interrater agreement was 84.1% (95% confidence interval [CI]: 75.5%–92.8%) for assessment 1 and 87.5% (95% CI: 78.4%–96.4%) for assessment 2, with kappa values 0.68 (95% CI: 0.50–0.82) and 0.75 (95% CI: 0.57–0.88). Average intrarater percent agreement was 95.0% (95% CI: 70.6%–100.0%) with average kappa 0.90 (95% CI: 0.50–1.00). CONCLUSION Substantial interrater and nearly perfect intrarater agreement was identified among surgeons assessing melanoma margins utilizing MART-1 immunostaining, demonstrating consistent and reproducible assessment of melanoma margins during Mohs cases.

BACKGROUND Mohs micrographic surgery (MMS) for cutaneous melanoma is becoming more prevalent, but surgical technique varies. OBJECTIVE To define variations in published techniques for MMS for melanoma. METHODS AND MATERIALS A systematic review was performed of PubMed, EMBASE, and Scopus databases to identify all articles describing surgical techniques for MMS for melanoma. Technical details were recorded for the preoperative, intraoperative, and postoperative phases of MMS. RESULTS Twenty-four articles were included. Mohs surgeons vary in how they assess clinical margins, how wide a margin they excise on the first MMS layer, and how they process tissue to determine tumor stage and margin clearance during MMS for melanoma. CONCLUSION Mohs micrographic surgery for melanoma is performed with varied surgical techniques. To establish best practices, additional research is necessary to determine how different techniques affect outcomes.

During the coronavirus disease 2019 (COVID‐19) pandemic, providers and patients must engage in shared decision making regarding the pros and cons of early versus delayed interventions for localized skin cancer. Patients at highest risk of COVID‐19 complications are older; are immunosuppressed; and have diabetes, cancer, or cardiopulmonary disease, with multiple comorbidities associated with worse outcomes. Physicians must weigh the patient's risk of COVID‐19 complications in the event of exposure against the risk of worse oncologic outcomes from delaying cancer therapy. Herein, the authors have summarized current data regarding the risk of COVID‐19 complications and mortality based on age and comorbidities and have reviewed the literature assessing how treatment delays affect oncologic outcomes. They also have provided multidisciplinary recommendations regarding the timing of local therapy for early‐stage skin cancers during this pandemic with input from experts at 11 different institutions. For patients with Merkel cell carcinoma, the authors recommend prioritizing treatment, but a short delay can be considered for patients with favorable T1 disease who are at higher risk of COVID‐19 complications. For patients with melanoma, the authors recommend delaying the treatment of patients with T0 to T1 disease for 3 months if there is no macroscopic residual disease at the time of biopsy. Treatment of tumors ≥T2 can be delayed for 3 months if the biopsy margins are negative. For patients with cutaneous squamous cell carcinoma, those with Brigham and Women's Hospital T1 to T2a disease can have their treatment delayed for 2 to 3 months unless there is rapid growth, symptomatic lesions, or the patient is immunocompromised. The treatment of tumors ≥T2b should be prioritized, but a 1‐month to 2‐month delay is unlikely to worsen disease‐specific mortality. For patients with squamous cell carcinoma in situ and basal cell carcinoma, treatment can be deferred for 3 months unless the individual is highly symptomatic.

BACKGROUND Extramammary Paget's disease (EMPD) is a rare intraepithelial malignancy with high recurrence rates following standard surgical treatments, ranging from 22% to 60% in large retrospective reviews. OBJECTIVE To evaluate the local recurrence rate of Mohs micrographic surgery (MMS) supplemented with intraoperative immunohistochemistry for cytokeratin-7 (MMS + CK-7) for primary and recurrent EMPD. MATERIALS AND METHODS Retrospective, multi-center, cross-sectional study of patients treated using MMS + CK-7. Demographic, clinicopathologic, treatment, and follow-up data were obtained by chart review. RESULTS The observed local recurrence rate for MMS + CK-7 is 3.3% (2/61 tumors) with a mean follow-up of 43.5 months (1–120 months). Local recurrence occurred in 2.3% (1/43) of primary tumors and 5.6% (1/18) of recurrent tumors. Kaplan–Meier 5-year tumor-free rates are 94.6% overall, 97.1% for primary tumors, and 80.0% for recurrent tumors. The Kaplan–Meier 5-year tumor-free rates for all EMPD tumors treated with MMS + CK-7 versus a historical cohort of MMS alone are 94.6% versus 72.0% (p = .012). CONCLUSION MMS + CK-7 is an effective treatment for EMPD, demonstrating improved outcomes compared with historical controls.