Introduction: Granulomatous prostatitis is a benign inflammatory condition of the prostate that may mimic prostatic adenocarcinoma on magnetic resonance imaging findings. Even in the era of multiparametric magnetic resonance imaging, the differential diagnosis of granulomatous prostatitis from malignancy remains difficult.
Case presentation: A 69-year-old man with abnormal magnetic resonance imaging and positron emission tomography/magnetic resonance imaging findings, and a prostate-specific antigen value of 2.48 ng/mL underwent prostate needle biopsy. He had a history of urinary tract infection 3 months prior to presentation. Multiparametric magnetic resonance imaging showed low-intensity signals on T2-weighted images, slightly high-intensity signals on diffusion-weighted images, and low values on apparent diffusion coefficients. The prostate imaging-reporting and data system version 2 score was 3. Histological examination revealed granulomatous prostatitis.
Conclusion: For patients with preceding urinary tract infections, granulomatous prostatitis should be considered as a differential diagnosis, even when magnetic resonance imaging and positron emission tomography suggest prostatic adenocarcinoma.
Keywords: MRI; PET; apparent diffusion coefficient; granulomatous prostatitis; multiparametric MRI; urinary tract infection.
© 2021 The Authors. IJU Case Reports published by John Wiley & Sons Australia, Ltd on behalf of the Japanese Urological Association.