Bone metastatic carcinoma coexisting with plasma cell myeloma: a case report.

Objective: Multiple myeloma is a clonal plasma cell proliferation often causing bone lytic lesions. It is sometimes challenging to differentiate these lytic lesions associated with multiple myeloma from bone destruction due to a metastasis. Although coexistence of solid tumors and plasma cell myeloma in one patient has been described, synchronous skeletal metastases from both neoplasms occurring in the same bone lesion is exceptional.