Metastatic extramedullary plasmacytoma: a case report and review of the literature of a rare pseudocarcinoma.

Extramedullary plasmacytomas are unusual plasma cell tumors arising outside the bone marrow. Most extramedullary plasmacytomas are solitary, but occasionally they disseminate, usually in conjunction with systemic myelomatosis. The authors report a case of disseminated extramedullary plasmacytoma with a picture suggestive of metastatic pancreatic carcinoma. This unusual presentation reconfirms the need for tissue diagnosis in all suspected cases of pancreatic carcinoma and demonstrates that extramedullary plasmacytoma can be an aggressive cancer without any sign of osseous or systemic disease.