Establishing Consensus for Mohs Micrographic Surgical Techniques in the Treatment of Melanoma in Situ for Future Clinical Trials: A Modified Delphi Study
Background: Mohs micrographic surgery (MMS) is a promising treatment modality for melanoma in situ (MIS). However, variations in surgical technique limit the generalizability of existing data and may impede future study of MMS in clinical trials. Methods: A modified Delphi method was selected to establish consensus on optimal MMS techniques for treating MIS in future clinical trials. The Delphi method was selected due to the limited current data, the wide range of techniques used in the field, and the intention to establish a standardized technique for future clinical trials. A literature review and interviews with experienced MMS surgeons were performed to identify dimensions of the MMS technique for MIS that (1) likely impacted costs or outcomes of the procedure, and (2) showed significant variability between surgeons. A total of 8 dimensions of technical variation were selected. The Delphi process consisted of 2 rounds of voting and commentary, during which 44 expert Mohs surgeons across the United States rated their agreement with specific recommendations using a Likert scale. Results: Five of eight recommendations achieved consensus in Round 1. All 3 of the remaining recommendations achieved consensus in Round 2. Techniques achieving consensus in Round 1 included the use of a starting peripheral margin of ≤5 mm, application of immunohistochemistry, frozen tissue processing, and resecting to the depth of subcutaneous fat. Consensus on the use of Wood’s lamp, dermatoscope, and negative tissue controls was established in Round 2. Conclusions: This study generated 8 consensus recommendations intended to offer guidance for Mohs surgeons treating MIS. The adoption of these recommendations will promote standardization to facilitate comparisons of aggregate data in multicenter clinical trials.
Xanthomatous Dermal Changes in a Patient With Locally Advanced Basal Cell Carcinoma Treated Using Vismodegib
Abstract: Basal cell carcinoma (BCC) is the most commonly diagnosed cutaneous cancer in the United States with more than 2.5 million treated annually. Genetic studies have revealed that approximately 90% of BCCs have a mutation in the hedgehog-signaling pathway. Patients with BCC usually have an excellent prognosis with surgical modalities, however, patients with locally advanced BCC may potentially experience significant cosmetic or functional impairment, with only surgical intervention. Vismodegib is a hedgehog pathway inhibitor that has been successful in treating patients with locally advanced BCC. We report a patient with BCC with a good response to vismodegib and a novel xanthomatous change in the excision specimen.