Mohs micrographic surgery for the treatment of primary cutaneous mucinous carcinoma

Primary cutaneous mucinous carcinoma (PCMC) is a rare adnexal tumour of the skin. Clinically, it appears as a benign cyst, but it has characteristic histopathology. It is a slow-growing tumour that rarely metastasizes but is associated with significant morbidity due to its high recurrence rate. Standard practice has been to surgically remove it with a wide local excision of 1-2-cm margin. In the last decade, increasing reports of Mohs micrographic surgery (MMS) for the treatment of PCMC have been described. MMS appears to reduce recurrence rates while allowing for more conservative margins. Given the rarity of PCMC, there are no prospective randomized control trials on treatment. This is the largest case series of PCMC treated by MMS to date.