-Case Reports-

A Case of Primary Malignant Lymphoma of the Prostate Gland Presenting as Right Lower Back Pain and Dysuria

Shotaro Yasuoka¹, Go Kimura¹, Yuka Toyama¹, Keichi Moriya², Keigo Takahashi¹, Ryo Matsuoka¹, Keita Shibayama¹, Kotaro Obayashi¹, Yasushi Inoue¹, Takao Shindo¹, Shigeki Iigaya¹, Yuki Endo¹, Jun Akatsuka¹, Tatsuro Hayashi¹, Satoko Nakayama¹, Tsutomu Hamasaki¹, Koiti Inokuchi² and Yukihiro Kondo¹

¹Department of Urology, Nippon Medical School Hospital
²Department of Hematology, Nippon Medical School Hospital

A 73-year-old man presented with right lower back pain and dysuria. Right hydronephrosis and a large pelvic large mass were seen on computed tomography (CT). Although his prostate-specific antigen (PSA) was 0.5 ng/mL, an irregularly enlarged, stony, hard prostate was palpable on digital rectal examination. A prostate tumor was suspected, and a transrectal prostate biopsy and right transurethral ureteral stent placement were performed. Histological and immunohistochemical studies revealed diffuse large B-cell lymphoma. Positron emission tomography-computed tomography showed abnormal uptake in the stomach, cecum, right obturator lymph nodes, para-aortic lymph nodes, and dorsal left kidney. No abnormal findings were seen on bone marrow histology. Clinical stage IVA was confirmed according to Ann Arbor criteria. The patient achieved a complete response after 8 cycles of combination chemotherapy with rituximab, pirarubicin, cyclophosphamide, vincristine, and prednisolone.

J Nippon Med Sch 2018; 85: 236-240

Keywords
malignant lymphoma, prostate, dysuria, hydronephrosis, International Prognostic Index (IPI)

Correspondence to
Shotaro Yasuoka, Department of Urology, Nippon Medical School Hospital, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan
syasuoka0317@gmail.com

Received, January 17, 2018
Accepted, February 20, 2018