Clinical significance of prostate volume and testosterone reduction on lower urinary tract symptoms in patients with prostate cancer undergoing androgen deprivation therapy

To investigate the effect of both prostate volume and serum testosterone changes on lower urinary tract symptoms in patients with prostate cancer undergoing androgen deprivation therapy. A total of 167 patients who received androgen deprivation therapy for prostate cancer treatment from January 2010 to August 2020 were enrolled in this retrospective study. Changes in the International Prostate Symptom Score (IPSS) in the patient groups stratified by prostate volume and the amount of testosterone reduction were assessed every 4 weeks until 12 weeks after androgen deprivation therapy initiation. Longitudinal mixed models were used to assess the adjusted effects of prostate volume and testosterone reduction on IPSS change. All mean values of IPSS-total score (IPSS-total), voiding subscore (IPSS-vs), and storage subscore (IPSS-ss) significantly decreased from baseline to week 12 in both patients with small (< 33 mL) and large (≥ 33 mL) prostates. The mean values of IPSS-total, IPSS-vs, and IPSS-ss similarly decreased in patients with large prostate with a baseline IPSS-total of ≥ 13. However, in those with small prostate, IPSS-ss specifically remained unchanged, while IPSS-total and IPSS-vs significantly decreased. In addition, only in patients with small prostate (< 33 mL), patients with lesser testosterone reduction (< Δ400 ng/dL) showed greater improvement in IPSS-ss by 7.5% compared with those with greater testosterone reduction (≥ Δ400 ng/dL). In conclusion, although androgen deprivation therapy generally improves lower urinary tract symptoms, it may worsen specifically storage symptoms in patients with relatively small prostate and greater testosterone reduction. Our finding suggests that testosterone may influence lower urinary tract symptoms in these patients.