The Influence of Endogenous Testosterone on Incidental Prostate Cancer after Transurethral Prostate Resection

Objective: The aim of the study was to test the hypothesis that endogenous total testosterone (TT) may relate to incidental prostate cancer (iPCA) in patients with lower urinary tract symptoms (LUTS) associated with prostate enlargement undergoing transurethral resection of the prostate (TURP). Methods: The hypothesis was tested in contemporary cohort of patients who underwent TURP because of LUTS due to prostate enlargement after excluding the suspect of PCA. In period running from January 2017 to November 2019, 389 subjects were evaluated. Endogenous testosterone was measured preoperatively between 8:00 and 10:00 o'clock in the morning. Relationships between TT and iPCA were evaluated by statistical methods. Results: Overall, iPCA was detected in 18 cases (4.6%) with clinical stage cT1a or International Society of Urologic Pathology (ISUP) < 2 in 11 patients (61.1%). Endogenous testosterone was inversely associated with age and BMI in the study population but not in the subgroup with iPCA in wholly endogenous TT strongly correlated to both number of chips involved by cancer (Pearson's correlation coefficient, r = 0.553; p = 0.017) and ISUP > 2 (r = 0.504; p = 0.033). The positive association of endogenous TT with both tumor load and tumor grade was confirmed by the linear regression model with high-regression coefficients for the former (regression coefficient, b = 0.307; 95% confidence interval, 95% CI: 0.062-0.551; and p = 0.017) as for the latter (b = 5.898; 95% CI: 0.546-11.249; and p = 0.033). Conclusions: Preoperative endogenous TT is associated with features of iPCA. The influence of iPCA on endogenous testosterone needs to be addressed by a large multicenter prospective trial.