Brain metastasis of Merkel cell carcinoma. Case report and review of the literature.

Merkel cell carcinoma (MCC) is a rare primary cutaneous neuroendocrine tumor that is locally aggressive and has potential for metastatic spread. However, brain metastases are rare, and therapy for such tumors has never reported. The authors present a 48-year-old woman with MCC of the left elbow and a right cerebellar metastasis. After the right cerebellar mass was totally resected, radiation treatment and chemotherapy were performed. Eight cases of brain metastasis have been reported in the literature, but only 5 have been presented in sufficient detail for analysis. Therapy for brain metastases has always been palliative whole-brain irradiation and chemotherapy except for our patient, who underwent total removal of the tumor and survived for 11 months without neurological deficit. Except in the case of 1 with a particularly radiosensitive MCC, the patients with brain metastases died within 9 months after detection of the brain lesions. If possible, aggressive excision of brain metastases as well as of the primary lesion should be done.