Lower pretreatment serum testosterone level predicts poor prognosis in the patients with metastatic hormone-sensitive prostate cancer undergoing androgen deprivation therapy.

Abstract

This study aimed to reveal the association between pretreatment serum testosterone levels and prognosis in patients with metastatic hormone-sensitive prostate cancer treated with androgen deprivation therapy. A total of 91 patients were included in this retrospective study. Clinical data were obtained through chart review. Multivariate cox proportional hazards analyses addressed the impact of variables on castration-resistant prostate cancer-free and overall survivals. During a median follow-up of 41.7months, 61 (67%) and 49 (54%) patients developed castration-resistant prostate cancer and died, respectively. The median castration-resistant prostate cancer-free and overall survivals were 15.5 and 59.9months, respectively. The cutoff value for discriminating between low- and high-testosterone levels was determined as 450ng/dl by calculating the receiver operating characteristic curve. Patients in the low-testosterone group (n=37) had a significantly higher body mass index, worse comorbidities represented by the higher Charlson comorbidity index and higher serum lactate dehydrogenase levels, than those in the high-testosterone group (n=54). Castration-resistant prostate cancer free and overall survivals were significantly shorter in the low-testosterone group than in the high-testosterone group (P=0.021 and P<0.001, respectively). Multivariate analysis identified testosterone level of <450ng/dl as an independent factor predicting development of castration-resistant prostate cancer (hazard ratio 2.28, P=0.007), along with high-volume disease and Gleason score 9-10. Similarly, testosterone level of <450ng/dl was independently associated with shorter overall survival (hazard ratio 2.84, P=0.006), along with higher Charlson comorbidity index, visceral metastasis and higher alkaline phosphatase level. Lower baseline serum testosterone levels predict poor prognosis in patients with metastatic hormone-sensitive prostate cancer.