Merkel cell carcinoma: a case report with treatment summary and updates.

Merkel cell carcinoma (MCC) is a rare primary cutaneous neoplasm known for its propensity to develop early regional and distant metastasis. Fewer than 400 cases occur annually in the United States. MCC ranks as the most deadly of cutaneous malignancies, with a fatality rate of approximately 25%. Because of its aggressive nature, MCC is often resistant to surgery, radiation, and chemotherapy regimens. Standardized treatment patterns have not been established, and difficulty arises finding appropriate treatment for the elderly, who comprise the majority of patients with MCC.