Does size matter in prostate cancer? A cross-sectional study on genital dimensions in Caucasian men

Background: Testosterone is crucial in male genital development during puberty. This study primarily aimed to compare genital size in Caucasian men with and without clinically significant prostate cancer (csPCa). The secondary aim was to assess genital size differences in csPCa patients stratified by tumor grade. Methods: We conducted an observational cross-sectional study on consecutive patients undergoing prostate biopsy. Each patient underwent systematic and cognitive-targeted transrectal biopsy. csPCa was defined as PCa with Gleason Score (GS) ≥7, tumor volume ≥0.5 cc, or extra-prostatic extension; other PCa and negative biopsies were classified as non-csPCa. Penile length was measured with the stretched test, and testicular volume by ultrasonography. Results: A total of 156 patients (64 csPCa and 92 non-csPCa) were enrolled. Median age was comparable between groups (68.9 vs. 66.6 years; p = 0.289). Median (IQR) stretched penile length (SPL) was 15.0 (14.0–16.3) cm in the csPCa group and 15.0 (13.0–15.2) cm in the non-csPCa group (p = 0.301). Median (IQR) right testicular volume was 12 (10–14) cc in both groups (p = 0.752), while left testicular volume was 10 (7–13) cc in the csPCa group and 12 (10–14) cc in the non-csPCa group (p = 0.172). Among csPCa patients, those with GS >7 had a longer SPL (16.0 (15–17) cm) compared to GS = 7 patients (14.5 (14–15) cm) (p = 0.012), with no significant differences in testicular volume. Conclusions: In Caucasian men, genital dimensions did not differ between those with and without csPCa. Within the csPCa group, longer SPL was observed in patients with higher-grade tumors. These findings suggest a possible association between genital size and tumor aggressiveness, which warrants further investigation.