Endogenous testosterone density predicts unfavorable disease at final pathology in intermediate risk prostate cancer

Objective: To test the hypothesis that endogenous testosterone (ET) density could be associated with tumor load (TL) in patients with intermediate risk (IR) prostate cancer (PCa).

Materials and methods: Endogenous testosterone density (ETD, ratio between ET and prostate volume [PV]), biopsy positive cores density (BPCD, the ratio between the number of positive cores and PV) and prostate-specific antigen density (PSAD, ratio between total PSA and PV) were retrospectively evaluated on a prospectively collected data on 430 patients with IR PCa submitted to radical prostatectomy (RP). Tumor load (TL) was measured as the percentage of prostatic volume occupied by cancer at final pathology. Unfavorable disease (UD) was defined as tumor upgrading (ISUP grading group 4, 5) and/or upstaging (pT3a or 3b) in prostate specimens. Associations were assessed by the logistic regression and linear regression models.

Results: Overall, UD, which was detected in 122 out of 430 IR patients (28.4%), was predicted by BPCD (odd ratio, OR = 1.356; 95% CI 1.048-1.754; p = 0.020) with a sensitivity 98.4% and overall accuracy 71.9%. On multivariate analysis, BPCD was independently predicted by PSAD (regression coefficient, b = 1.549; 95% CI 0.936-2.162; p < 0.0001), ETD (b = 0.032; 95% CI 0.023-0.040; p < 0.0001) and TL (b = 0.009; 95% CI 0.005-0.014; p < 0.0001). As BPCD increased, ETD and ET levels increased accordingly, but patients with BPCD > 1.0%/mL had significantly lower ET levels.

Conclusions: As ETD increased, BPCD and TL increased, accordingly; furthermore, patients with lower ET levels were more likely to have occult UD. The influence of tumor load, and unfavorable disease on ET and ETD needs to be addressed by further studies.