[A case of malignant lymphoma of the prostate].

We report a case of primary malignant lymphoma of the prostate. A 76-year-old man was refer to our clinic with a chief complaint of dysuria. Based on a benign prostatic hypertrophy, transurethral resection of the prostate was performed. Histological findings showed diffuse, large cell type malignant lymphoma. His clinical stage was 1 A prostate (+) according to the Ann Abor classification. The combination chemotherapy with THP-COP was performed for 3 courses, followed by irradiation at 30 Gy. His prostate has showed no recurrence for 10 month after treatment. Primary malignant lymphoma of the prostate is rare. About 30 cases have been reported in the japanese literature. Preoperative diagnosis of malignant lymphoma of the prostate is difficult. All cases have been diagnosed after prostatic surgery or biopsy.