Relationship between body composition and hormone sensitivity for androgen deprivation therapy in metastatic prostate cancer patients.

Abstract

e16500 Background: Obesity has been reported to have an influence on prostate cancer incidence and its aggressive phenotype but this remains controversial. Body mass index (BMI) is useful marker of obesity but it does not represent body fat percentage precisely. The relationship between body composition and the efficacy of androgen deprivation therapy (ADT) has not well been studied. Here, we investigated whether body composition features including the psoas muscle may be predictive factors of ADT. Methods: This study enrolled hormone-sensitive metastatic prostate cancer patients who were treated with primary ADT from April 2006 to August 2009 in Kyushu University Hospital, and who underwent a CT scan prior to primary ADT for calculating body fat percentage, psoas muscle ratio (psoas muscle, cm3/height, cm2), and BMI. Results: Of the 178 patients enrolled, 60 patients died during follow-up. Median follow-up was 32 months, and progression-free survival (PFS) and overall survival (OS) were 28 and 80 months, respectively. Multivariate analysis revealed that the psoas muscle ratio was correlated with OS (hazard ratio [HR]: 0.448; 95% CI = 0.206–0.922; P= 0.028). Conclusions: This study demonstrated that higher psoas muscle ratio predicts longer OS among non-localized prostate cancer patients treated with primary ADT. [Table: see text]