[Cases of bacillus Calmette-Guerin-induced granulomatous prostatitis and prostatic stromal invasion of the bladder carcinoma in situ, showing similar clinical findings].

Intravesical instillation of bacillus Calmette-Guerin (BCG) is the first-line therapeutic option for flat carcinoma in situ (CIS) of the bladder. Intravesical BCG instillation has been demonstrated to cause granulomatous prostatitis. Bladder CIS often also is known to show prostatic stromal invasion. We report a case of BCG-induced granulomatous prostatitis and a case of prostatic stromal invasion of bladder CIS accompanied by locally advanced prostate cancer, which showed similar clinical findings after the intravesical BCG therapy. In these 2 patients, urinary symptoms such as dysuria were prolonged regardless of anti-tuberculous medication, hard nodules were palpable at the prostate, and hypoechoic lesions were visualized by transrectal ultrasound. Both patients were treated by transurethral resection of the prostate, and the diagnoses were made by histopathological examination. Urinary symptoms were resolved in both patients after surgery, but the prostatic stromal tumor showed recurrence of growth. We report the usefulness of transurethral resection of the prostate for medication-resistant BCG-induced granulomatous prostatitis, and the importance of the correct diagnosis of prostatic stromal invasion of bladder CIS especially in the cases with concurrent prostate cancer.