[A case of multiple myeloma presenting as giant chest wall tumors with calcification]

A 60-year-old man was admitted for investigation of an abnormality detected in chest radiography: a giant tumor with calcification in the right middle lung field. A computed tomography (CT) scan revealed multiple tumors with calcification on the posterior chest wall. Histological analysis of the tumor specimen obtained by surgical biopsy demonstrated an increasing number of plasma cells accompanied with the deposition of amyloid. A bone marrow biopsy contained over 50% of plasma cells. We therefore diagnosed these tumors as multiple myeloma. It has been reported that multiple myeloma is usually characterized by osteolytic lesions; osteosclerotic changes are rare. Multiple myeloma should be taken into account as one of the causes of a chest wall tumor even if it is diffusely calcified.