Effect of Bacillus Calmette-Guerin Exposure on Prostate Cancer Detection Using Magnetic Resonance Imaging: A Cohort...

Area of Science:

• Urology
• Oncology
• Radiology

Background:

• Granulomatous prostatitis is a condition that can resemble prostate cancer.
• Bacillus Calmette-Guérin (BCG) treatment for urothelial carcinoma can lead to granulomatous prostatitis.

Purpose of the Study:

• To evaluate if BCG-exposure confounds prostate cancer diagnosis using multiparametric prostate magnetic resonance imaging (mpMRI) and Prostate Imaging and Data System (PI-RADS) classification.
• To assess the impact of BCG-exposure on the risk of malignancy and significant tumor in patients undergoing mpMRI-targeted prostate biopsy.

Main Methods:

• A cohort study included 712 males at risk for prostate cancer undergoing mpMRI-targeted biopsy.
• Patients with prior BCG-exposure within 3 years were compared to unexposed patients.
• Statistical analyses included chi-square and logistic-regression tests.

Main Results:

• BCG-exposure was associated with a significantly lower risk of malignancy (OR: 0.15) and significant tumor (OR: 0.39).
• For PI-RADS 4 lesions, malignancy risk was 61.6% in non-exposed vs. 16.7% in BCG-exposed patients.
• For PI-RADS 5 lesions, malignancy risk was 90.7% in non-exposed vs. 22.2% in BCG-exposed patients.

Conclusions:

• Granulomatous prostatitis due to BCG-exposure acts as a confounding factor in prostate MRI interpretation.
• The risk of malignancy and significant tumor is substantially lower in BCG-exposed patients across PI-RADS categories.
• This finding is crucial for accurate diagnosis and management of prostate cancer in BCG-treated patients.