Primary Mucinous Carcinoma of the Skin: The Mayo Clinic Experience Over the Past 2 Decades

BACKGROUNDPrimary mucinous carcinoma of the skin (PMCS) is a rare adnexal eccrine sweat gland neoplasm, often mistaken for metastasis from extracutaneous sites or misdiagnosed. Primary mucinous carcinoma of the skin is a slow-growing tumor with a high recurrence rate after conventional excision.OBJECTIVETo describe clinicopathologic features, rate of recurrence, and metastasis and to review relevant literature.MATERIALS AND METHODSThe authors identified patients with PMCS treated from January 1992 through December 2012 at Mayo Clinic. The authors retrospectively reviewed medical records and histology slides. Relevant publications were identified through Ovid MEDLINE and PubMed.RESULTSSix patients with PMCS were identified (1 male). The average age at diagnosis was 63 years. Tumor size ranged from 0.5 to 2.0 cm, and all were confined within the dermis. No evidence of metastatic mucinous adenocarcinoma was documented at the time of diagnosis. Five patients underwent Mohs micrographic surgery, and 1 was treated with wide local excision. There were no episodes of recurrence or metastases after a median follow-up of 20 months (range, 0.5-207 months).CONCLUSIONMohs micrographic surgery may offer reduced recurrence rates and better outcomes in PMCS. Further studies with longer follow-up and bigger cohorts of patients with PMCS are warranted.