Metastatic Merkel cell carcinoma in the rectum: report of a case.

Merkel cell carcinoma is a rare, aggressive skin malignancy of neuroendocrine origin with predominant occurrence in the elderly males. Approximately 50 percent of patients with Merkel cell carcinoma develop distant metastasis at some point during the disease course; hence, Merkel cell carcinoma always has a poor prognosis. Distant metastasis has never been disclosed in the rectum to the best of our knowledge. We present a 76-year-old male with clinical manifestation of massive hematochezia and final diagnosis of metastatic Merkel cell carcinoma in the rectum. We conclude that radical resection of rectal metastatic Merkel cell carcinoma is important in the management strategy of a patient with recurrence and lymph node metastases.