Current Use of Neoadjuvant Hedgehog Inhibitors Among Mohs Surgeons: Results of a Cross-Sectional Survey

Recent studies have demonstrated functional and cosmetic benefits with the use of hedgehog pathway inhibitors in the neoadjuvant setting for basal cell carcinoma (BCC). In one open label study, investigators demonstrated a mean decrease in surgical defect size by 27% for locally advanced BCCs with 3 months of treatment with vismodegib.¹ In the VISMONEO neoadjuvant study, investigators found a 29%-66% size reduction in high risk BCCs after treatment with vismodegib for 4-10 months.² And in the 27 patients who underwent surgery in the VISORB neoadjuvant trial for BCCs threatening the lacrimal drainage system, 67% of patients had no histologic evidence of disease during subsequent surgical intervention.³ Promising results in the literature have led Mohs surgeons to incorporate vismodegib as a neoadjuvant tumor modifying agent prior to definitive Mohs surgery. The purpose of this study is to investigate the current use of neoadjuvant therapy by Mohs surgeons for the treatment of BCC.

An anonymous REDcap survey was approved by the American College of Mohs Surgery (ACMS) executive committee and distributed to its members via their seasonal ACMS newsletter. Participants who completed the survey and reported use of neoadjuvant hedgehog pathway inhibitors prior to Mohs surgery answered follow-up multiple choice and free-text questions about parameters for use. Participants who reported not using neoadjuvant hedgehog pathway inhibitors prior to Mohs surgery answered yes/no questions about reasons they were hesitant to use hedgehog inhibitors. Differences between groups were analyzed with chi-square and t-tests with statistical significance defined as P<0.05.

A total of 50 participants completed the survey (mean age 45+10, 30 [60%] male, 35 [70%] in private practice). A total of 11 (22%) participants reported current use of neoadjuvant hedgehog inhibitors prior to Mohs surgery. Regarding size, 4/11 (36%) reported initiating hedgehog pathway inhibitors for BCCs greater than 3.0 cm and 7/11 (64%) reported size was not a factor in decision to use hedgehog pathway inhibitors. Regarding location, 2/11 (18%) participants reported use for tumors in area H of the Mohs appropriate-use criteria, 5/11 (45%) reported use in tumors with periocular involvement, and 4/11 (36%) reported location was not a factor. For target reduction in tumor size prior to Mohs surgery, 1/11 (9%) participants reported 21-30%, 4/11 (36%) participants reported greater than 30%, and 6/11 (55%) reported reduction in size was not a factor. For average length of therapy prior to Mohs surgery, 1/11 (9%) participants reported 1-2 months, 6/11 (55%) participants reported 3-4 months, and 4/11 (36%) participants reported 4-6 months. All participants reported vismodegib was the hedgehog pathway inhibitor of choice. The average number of BCC cases treated with neoadjuvant hedgehog pathway inhibitors per year was 2.36.