[A case of solitary plasmacytoma that originated in a rib].

A 52-year-old woman was admitted to our hospital with the chief complaint of left anterior chest pain. A chest X-ray showed a tumor shadow in the left 4th rib. No abnormalities were detected in peripheral blood and aspirated bone marrow samples. The tumor was surgically resected with the involved bone, the intercostal muscle and the parietal pleura. The resected specimen contained a 3 x 6 x 3 cm lesion, and histological investigation of the tumor revealed a plasmacytoma of the rib. It relapsed as a multiple myeloma within two months after surgery. Chemotherapy was administered and the bone lesions were observed to disappear. We believe that the best way to treat solitary plasmacytoma is to first resect the solitary tumor, and then to add cobalt irradiation and chemotherapy after surgery.