MERKEL CELL-CARCINOMA

BACKGROUND. Merkel cell carcinoma is an aggressive tumor with nonspeci fic clinical features. The prognosis in general is worse than malignan t melanoma. Local recurrence rates are high with one-third of patients having recurrence within one year of excision. The tumor invades bloo d vessels and lymphatics. This frequent lymphatic dissemination leads later to satellite lesions and recurrence. Distant metastases occur in one-third of patients. One-, two- and three-year survival rates are p oor, being estimated at 88%, 72%, and 55%, respectively.OBJECTIVE. TO increase awareness of the behavior of this uncommon tumor. METHODS. A review of the current literature and recommendations regarding this tu mor. RESULTS. Wide local excision with 3-cm margin shows significant r eduction in local recurrence compared with 2-cm margins. Two-thirds of patients with local recurrence ultimately die from their disease. Rad iation therapy has a role to play in the local and regional clearance of the tumor. CONCLUSION. Prompt diagnosis and surgical excision are n ecessary to improve survival. Mohs micrographic surgery offers potenti al advantages in evaluating both the lateral and the deep margins. Fol low-up studies of patients treated with this modality will be benefici al.