Mohs Micrographic Surgery for the Treatment of Basal Cell Carcinoma

Abstract

Vulval basal cell carcinoma (BCC) is a relatively uncommon malignancy, accounting for < 5% of all vulval neoplasms and only 1% of all BCCs. There are no current clinical guidelines for the management of genital BCC, and therapeutic options include wide local excision, topical imiquimod and cryotherapy. Vulval BCC should be considered a high-risk subtype due to the high rate of local recurrence, up to 20% in reported cases series. Patients usually present with nonspecific symptoms, the clinical features are often atypical, and therefore the presentation is often delayed. Lesions are difficult to delineate clinically and the borders are often poorly circumscribed. All of these factors may account for the relatively large size of lesions treated at presentation (> 1 cm). We report six patients with vulval BCC treated at our centre using Mohs micrographic surgery over the last 3 years. Cases were extracted from the Mohs database between 2013 and 2015. The median age at presentation was 71.5 years. The predominant histological subtype was nodular (five of six). Four of the patients presented with primary lesions and two cases were of a recurrence. Recurrence occurred following treatment elsewhere with curettage, imiquimod and primary excision. One patient had treatment of a presumed genital wart using cryotherapy. Over half of the presenting lesions were larger than 1 cm (four of six) and were located mostly on the labium majus (five of six). Only one was located on the labium minus. All cases were closed via direct primary closure. The postoperative outcome was excellent in all cases at the 3-month follow-up assessments, and there were no reported complications or functional issues following surgery. There have been no other reported case series of outcomes for the use of Mohs surgery for the treatment of vulval BCC. Although Mohs surgery is clearly critical for tissue preservation for important anatomical sites such as the clitoris, we would also emphasize that this procedure should be favoured based on the reportedly high rates of recurrence, as well as the difficulty in assessing clinical margins.