Factors associated with testosterone recovery after androgen deprivation therapy in patients with prostate cancer

PURPOSE: We investigated factors affecting testosterone recovery after androgen deprivation therapy (ADT) withdrawal in patients with prostate cancer. MATERIALS AND METHODS: The medical records of patients who underwent radical prostatectomy with ADT were retrospectively reviewed. In all, 221 patients were included in the analysis. Testosterone recovery was defined as supra-castration (SC) (testosterone levels in serum >50 ng/dL) or out of hypogonadism (OH) (>300 ng/dL) after ADT withdrawal. Kaplan-Meier analyses were used to estimate testosterone recovery after ADT cessation. Cox regression analyses were used to determine the factors affecting the recovery of testosterone. RESULTS: After ADT, 206 patients (93.2%) recovered to the SC level and 122 patients (55.2%) recovered to the OH level. Patients treated with ADT for ≤18 months recovered to OH in a mean of 6.8 months (74.6%), but patients treated with ADT for >18 months recovered in a mean of 9.7 months (27.5%). In multivariate analyses, age (hazard ratio [HR], 0.915; p<0.001), serum level of sex hormone-binding globulin (SHBG) (HR, 1.015; p=0.002), initial testosterone level (HR, 1.002; p=0.002), and ADT duration (HR, 0.915; p<0.001) were associated with recovery to the OH level after ADT withdrawal, and hypertension (HR, 0.697; p=0.029) and duration of ADT (HR, 0.979; p=0.012) were significantly associated with recovery to SC. CONCLUSIONS: In patients treated with ADT for ≤18 months, testosterone recovers to the OH level more often and faster after ADT cessation. Age, SHBG level, initial testosterone level, and ADT duration are associated with testosterone recovery.