Intravesical BCG therapy-induced granulomatous prostatitis in a patient with non-muscle invasive bladder cancer and prostate adenocarcinoma

Granulomatous prostatitis (GP) is a rare inflammatory condition that may mimic prostate cancer (PC) progression. We present the case of a 64-year-old man with low-risk PC on active surveillance who developed Bacillus Calmette-Guérin (BCG)-induced GP following intravesical therapy for non-muscle invasive bladder cancer. Clinical and imaging findings suggested PC progression, but biopsy confirmed granulomatous inflammation without malignancy upstaging. This case underscores the similarities in clinical presentation, as well as the importance of histopathological evaluation in differentiating GP from PC.