A review of Mohs micrographic surgery for skin cancer. Part 1: Melanoma and rare skin cancers.

Mohs micrographic surgery (MMS) is a precise and effective method commonly used to treat high-risk basal cell carcinoma and squamous cell carcinoma on the head and neck. Although the majority of evidence for MMS relates to keratinocyte cancers, there is published evidence for other types of skin cancer. This review aims to discuss the evidence for using MMS to treat six different types of skin cancer [malignant melanoma, lentigo maligna, dermatofibrosarcoma protuberans, atypical fibroxanthoma (AFX), microcystic adnexal carcinoma and pleomorphic dermal sarcoma (PDS)] particularly in the context of survival rates and cancer recurrence. These cancers were chosen because there was sufficient literature for inclusion and because MMS is most useful when cancers are contiguous, rather than for cancers with marked metastatic potential such as angiosarcoma or Merkel cell carcinoma. We searched MEDLINE, PubMed and Embase using the keywords: 'melanoma', 'mohs micrographic surgery', 'lentigo maligna', 'dermatofibrosarcoma protuberans', 'atypical fibroxanthoma', 'microcystic adnexal carcinoma' and 'pleomorphic dermal sarcoma' along with their appropriate synonyms, to identify the relevant English-language articles from 2000 onwards, given that literature for MMS on nonkeratinocyte cancers is sparse prior to this year. AMSTAR (A MeaSurement Tool to Assess systematic Review) was used to assess the validity of systematic reviews. Further high-quality, multicentre randomized trials are necessary to establish the indications and efficacy of MMS for rarer cancers, particularly for AFX and PDS, for which only limited studies were identified.