The effect of 5-alpha reductase inhibitors on the detection of prostate cancer with multiparametric magnetic resonance imaging and prostate biopsy.

Aim: To evaluate the effect of 5 alpha-reductase inhibitor (5-ARI) treatment on prostate cancer detection by multiparametric magnetic resonance imaging (mpMRI).

Methods: We retrospectively collected data on 429 patients who underwent mpMRI before prostate biopsy in the Urology Department of Giresun University Training and Research Hospital between March 2018 and December 2021. The patients were categorized as those who had never been treated with 5-ARI (n=359) and those who were treated with 5-ARI for more than six months (n=70). The two groups were compared in terms of age, mpMRI findings, and pathology results.

Results: The number of patients with Prostate Imaging-Reporting and Data System (PIRADS) 3 score was significantly higher in the 5-ARI group (37.1% vs 20.6%; P=0.009). The groups did not differ in terms of malignant pathological findings (48.5% in the non-5-ARI vs 47.1% in the 5-ARI group; P=0.505). The detection rates of malignant pathological findings in PIRADS 3 and PIRADS 5 patients were similar between the 5-ARI and non-5-ARI group. However, malignancy detection rate in PIRADS 4 patients was significantly higher in the non-5-ARI group (P=0.031). In the non-5-ARI group, the sensitivity was 56.4% and the specificity was 79.7%. In the 5-ARI group, the sensitivity was 84.9% and the specificity was 56.8%.

Conclusion: In patients with suspected prostate cancer, 5-ARI intake may alter lesion mpMRI characteristics and PIRADS distribution on mpMRI. 5-ARI intake should be reported to the radiologist.