Prostate magnetic resonance imaging findings in patients treated for testosterone deficiency while on active surveillance for low-risk prostate cancer

Objective To investigate the multiparametric prostate magnetic resonance imaging (mpMRI) findings in patients treated with testosterone replacement therapy (TRT) while on active surveillance for low-risk prostate cancer. Methods We retrospectively reviewed 12 patients who underwent mpMRI before and after TRT while on active surveillance. Changes in serum testosterone level, prostate-specific antigen (PSA), prostate biopsy findings, prostate volume, and Prostate Imaging Reporting and Data System Version 2 (PI-RADSv2) score before and after TRT were summarized. Results After TRT, there was a significant increase in serum testosterone (516.5 ng/dl vs. 203.0 ng/dl), PSA (4.2 ng/ml vs. 3.3 ng/ml), and prostate volume (55.2 cm³ vs. 39.4 cm³). In total, 2 patients had biopsy progression during the study period. The PI-RADSv2 scores before and after TRT were unchanged in 10/12 patients; none of these demonstrated biopsy progression on post-TRT. The PI-RADSv2 scores increased after TRT in 2/12 patients; both showed Gleason score upgrade on follow-up biopsy. Of these 2 patients, 1 patient underwent radical treatment due to clinical progression. The area under the curve for detecting biopsy progression calculated from PI-RADSv2 score after TRT was 0.90, which was better than that calculated from post-TRT PSA level (0.48). Conclusions After TRT, mpMRI findings remained stable in patients without biopsy progression, whereas PI-RADSv2 score increase was identified in patients with Gleason score upgrade on follow-up biopsy.