Safety of Megestrol Acetate in Palliating Anorexia-Cachexia Syndrome in Patients with Castration-Resistant Prostate Cancer

ABSTRACT

There are concerns whether megestrol acetate (MA) stimulates the growth of prostate cancer in castration-resistant prostate cancer (CRPC). We evaluated the effect of cumulative doses of MA on the disease-specific survival (DSS) in patients with CRPC who were receiving Docetaxel-based chemotherapy. From July 2003 through June 2009, we identified 109 consecutive patients with CRPC and who had received docetaxel-based chemotherapy. Of these patients, 68 (62.4%) have not received MA, whereas 21 patients (19.3%) and 20 patients (18.3%) had received low dose MA (total 18,400 mg), respectively. We assessed the effect of several variables on DSS. None of the clinicopathological variables differed among the three groups. When comparing DSS using Kaplan-Meier analysis, there was no statistically significant survival differences among the three groups (P = 0.546). Using multivariate Cox proportional analyses with backward elimination, the number of docetaxel cycles was only significant factor predicting DSS (HR 0.578, 95% CI 0.318-0.923, P = 0.016). Cumulative doses of MA as adjuvant treatment for patients with CRPC and who are receiving docetaxel-based chemotherapy, did not affect their DSS. Therefore, MA can be safely administered in cachexic patients with CRPC.