Primary Urethra Non-Hodgkin Lymphoma in a 46-Year-Old Man on FDG PET/CT.

Primary lymphoma of the male urethra is exceptionally rare. A 46-year-old man complained of low back pain, hematuria, and dysuria. Cystourethroscopy revealed a pale, annular thickening of the urethral mucosa. A biopsy revealed that the patient had diffuse large B-cell lymphoma. Before treatment, an 18 F-FDG PET/CT was used for staging. The urethra and left inguinal lymph nodes showed increased FDG uptake. The patient was then diagnosed with primary urethral lymphoma that had invaded the left inguinal lymph node.