Changes in sex hormone levels after radical prostatectomy: Results of a longitudinal cohort study

The changes in testosterone and gonadotropin levels in patients who have undergone radical prostatectomy (RP) for clinically localized prostate cancer (PCa) remain unclear. The aim of the present study was to prospectively evaluate the changes in serum testosterone (Te), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels in the early months after RP for PCa and the correlation between these hormones at various follow-up times. A total of 100 male patients with clinically localized PCa were consecutively included in the study. The serum levels of Te, LH and FSH were measured prior to RP (baseline) and at 1 and 3 months post-operatively. Changes in the levels of Te, LH and FSH between the baseline and at 1 and 3 months after RP were analyzed with paired sample t-tests. The correlations between LH and Te levels at the various follow-up times were evaluated with a Spearman's rank correlation coefficient. At 1 month subsequent to RP, the Te levels were significantly decreased (baseline vs. 1 month, P=0.021) and subsequently recovered to the pre-operative value at 3 months (baseline vs. 3 months, P=0.372). The mean Te level at baseline was 15.3 nmol/l, while at 1 and 3 months it was 13.8 and 14.4 nmol/l, respectively. By contrast, the levels of LH and FSH were significantly increased at 1 and 3 months post-surgery, compared with the baseline value (baseline vs. 1 or 3 months, P<0.0001). The pre-operative correlation between LH and Te was lost 1 month after RP and recovered after 3 months. Notably, the LH level at 1 month was markedly correlated with the Te levels recorded after 3 months. In the present study, patients developed compensated hypergonadotropic hypogonadism 3 months after RP.