[Multiple myeloma causing obstructive jaundice by extramedullary plasmacytoma after Bence Jones protein loss--an autopsy case report].

A 63-year-old man was admitted to our hospital with a chief complaint of general malaise in March 1986. A diagnosis of Bence Jones protein (kappa) type of multiple myeloma was made from increased atypical plasma cells in the bone marrow, urinary BJP (kappa) and osteolytic lesions. Urinary BJP (kappa) was decreased by MP and VENP therapies. In April 1987, he visited us again with the complaint of pain on the left shoulder. An examination revealed multiple osteolytic lesions and bilateral pleural effusion containing atypical plasma cells. Jaundice was developed at the end of July 1987. An ultrasound examination revealed a hypoechoic mass in the area of pancreatic head. The effusion was gradually increased without response to the treatment. He died of respiratory failure on July 31, 1987. On autopsy, extramedullary plasmacytoma was found in the head of pancreas. It was a rare case of multiple myeloma in which pleural effusion and multiple plasmacytomas, and finally obstructive jaundice were developed although urinary BJP (kappa) was reduced by treatment.