The role of multiparametric magnetic resonance ımaging in the diagnosis of granulomatous prostatitis mimicking prostate cancer

Abdom Radiol (NY). 2024 Jul;49(7):2305-2310. doi: 10.1007/s00261-024-04288-7. Epub 2024 Apr 23.

Abstract

Purpose: Aimed to investigate the role of multiparametric magnetic resonance imaging (mp-MRI) in the diagnosis of granulomatous prostatitis caused by intravesical Bacillus Calmette-Guérin (BCG).

Methods: In this prospective, single-center study, 10 male patients who were given intravesical BCG due to intermediate- and high-risk bladder cancer were included. Before transurethral resection of bladder tumors (TURB), all patients were evaluated by mp-MRI, serum prostate-specific antigen (PSA), and digital rectal examination (DRE). Serum PSA levels and DRE findings were evaluated before and after intravesical BCG treatment. Prostate mp-MRI was performed for patients with elevated levels of serum PSA and/or with abnormal DRE findings. Then, MRI fusion + systematic prostate biopsy was performed. Demographic data of the patients before and after intravesical BCG were compared.

Results: The average age of the patients was 66.9 years (55-87 years). While PSA was 1.7 ng/ml before intravesical BCG treatment, it was 4.3 ng/ml after intravesical BCG treatment (p = 0.005). PSA density (PSAD) was 0.04 and 0.10 before and after the treatment, respectively (p = 0.012). DRE findings of all patients were normal before the treatment. However, abnormal findings were detected in 80% of them after the treatment (p = 0.008). PI-RADS ≥ 3 lesions were found to be significantly higher in all patients after intravesical BCG (p = 0.004).

Conclusion: Granulomatous prostatitis is a rare complication of intravesical BCG. High PSA, abnormal DRE, and PI-RADS ≥ 3 lesions detected after intravesical BCG should suggest granulomatous prostatitis and unnecessary biopsies may be avoided.

Keywords: Bacillus Calmette-Guerin; Image-guided prostate biopsy; Multiparametric magnetic resonance imaging; Prostatitis.

MeSH terms

  • Administration, Intravesical
  • Aged
  • Aged, 80 and over
  • BCG Vaccine* / adverse effects
  • Diagnosis, Differential
  • Digital Rectal Examination
  • Granuloma* / chemically induced
  • Granuloma* / diagnostic imaging
  • Humans
  • Male
  • Middle Aged
  • Multiparametric Magnetic Resonance Imaging* / methods
  • Prospective Studies
  • Prostate-Specific Antigen / blood
  • Prostatic Neoplasms / diagnostic imaging
  • Prostatitis* / chemically induced
  • Prostatitis* / diagnostic imaging
  • Urinary Bladder Neoplasms / diagnostic imaging
  • Urinary Bladder Neoplasms / prevention & control

Substances

  • BCG Vaccine
  • Prostate-Specific Antigen