Extramedullary plasmacytoma is an uncommon neoplasm and it occurs most frequently in the upper respiratory tract. Among the extramedullary plasmacytomas, retroperitoneal plasmacytoma is an extremely rare tumor with only about 10 cases having been reported in the world. Herein, we reported on a extramedullary plasmacytoma in the retroperitoneum. A 68-year-old man presented with left flank pain. The initial clinical diagnosis was retroperitoneal tumor. Retroperitoneal tumor mass excision along with left nephrectomy was performed and the histopathology showed plasmacytoma. There was no evidence of multiple myeloma. After the operation, he was treated with radiotherapy and the out-patient department follow-up is going on.
Aged ; Diagnosis ; Flank Pain ; Follow-Up Studies ; Humans ; Multiple Myeloma ; Nephrectomy ; Outpatients ; Plasmacytoma* ; Radiotherapy ; Respiratory System ; Retroperitoneal Neoplasms