Preoperative endogenous total testosterone predicts prostate cancer progression: results in 580 consecutive patients treated with robot assisted radical prostatectomy for clinically localized disease

Purpose: To test the role of endogenous total testosterone (ETT) as a predictor of prostate cancer (PCa) progression in patients treated with robot assisted radical prostatectomy for clinically localized disease. Methods: Between November 2014 and December 2019, 580 consecutive patients were evaluated. Preoperative ETT levels were classified as ≤ 350 ng/dL vs. > 350 ng/dL. The associations between ETT levels and the risk of PCa progression, defined as any event of biochemical recurrence and/or local recurrence and/or distant metastases, or other clinical and pathological factors were evaluated by regression analyses. Results: Preoperative ETT levels resulted ≤ 350 ng/dL in 173 (29.8%) patients. Disease progression occurred in 101 (17.1%) cases. Progressing patients were more likely to present with PSA levels > 10 ng/mL, as well as with unfavorable tumor grade (ISUP 4-5) and stage (pT3b) at final pathology, but less likely to have ETT levels ≤ 350 ng/mL. On clinical multivariable Cox regression models, ETT ≤ 350 ng/mL exhibited a statistically significant protective effect on tumor progression (hazard ratio: 0.57, p = 0.013). Subjects presenting with ETT levels ≤ 350 ng/mL were less likely to harbor ISUP 4-5 tumor grade either at biopsy (odds ratio [OR]: 0.46, p = 0.028) or final pathology (OR: 0.45, p = 0.032). Conclusions: At PCa diagnosis, ETT, which associates with ISUP tumor grade, is an independent predictor of disease progression. Accordingly, as ETT decreases to levels ≤ 350 ng/dL, the risk of unfavorable tumor grade decreases, and a more favorable prognosis is expected. Preoperative ETT levels may allow further patient stratification along prognostic risk groups.