Abstract
Merkel cell carcinoma (MCC), first described by Toker in 1972, is a rare superficial subcutaneous carcinoma presumably derived from neurotactile cells of the dermis. Lymph node metastasis is frequent, but bone metastasis is rarely reported. A 66 year-old man was referred showing an osteolytic destructive lesion in his right proximal tibia. Simple resection of a left buttock tumor had been performed in another hospital two years previously. Open biopsy revealed small round cell carcinoma, positive to EMA, NSE, S-100, and negative to keratin, LCA, which all concurred with the primary buttock tumor. After knee rotation-plasty by segmental amputation, six courses of chemotherapy with adriamycin and ifosfamide was performed, diffuse metastasis in the pelvis was reduced by lineac 46 Gy irradiation. In our study, MCC is thought to be neurogenic as well as epithlial. Electron microscopy revealed multiple membrane bound neurosecretory granules.
