A Merkel cell carcinoma treatment algorithm.

Merkel cell carcinoma is a rare and aggressive malignancy of the skin. Approximately 2000 cases of Merkel cell carcinoma have been reported since its first published description in 1972. Owing to its rarity, scientific studies have been difficult. Our current knowledge is based on retrospective case studies and case reports. Although many treatment modalities have been used, no definitive management strategy has yet been elucidated. Current strategies include local excision, Mohs surgery, sentinel lymph node biopsy, lymph node dissection, irradiation, and chemotherapy. We present several recent cases to demonstrate the heterogeneity of this cancer, then we review the literature to suggest a treatment algorithm for this rare but aggressive cancer.