Weight Loss for Obese Prostate Cancer Patients on Androgen Deprivation Therapy.

PURPOSE Excess fat mass (FM) contributes to poor prostate cancer (PCa) prognosis and comorbidity. However, FM gain is a common side effect of androgen deprivation therapy (ADT). We examined the efficacy of a 12-week weight loss intervention to reduce FM and maintain lean mass (LM) in ADT-treated obese PCa patients. METHODS Fourteen ADT-treated obese PCa patients (72±9years, 39.7±5.4% body-fat) were recruited for a self-controlled prospective study, with 11 completing the 6-week control period, followed by a 12-week intervention comprising 300 minutes/week of exercise including supervised resistance training and home-based aerobic exercise, and dietitian consultations advising a daily energy deficit (2100-4200kJ) and protein supplementation. Body composition was assessed by dual x-ray absorptiometry. Secondary outcomes included muscle strength (1RM), cardiorespiratory fitness (VO2max), and blood biomarkers. RESULTS There were no significant changes during the control period. Patients attended 89% of supervised exercise sessions and 100% of dietitian consultations. No changes in physical activity or energy intake were observed. During the intervention, patients experienced significant reductions in weight (-2.8±3.2kg, p=0.016), FM (-2.8±2.6kg, p<0.001), and trunk FM (-1.8±1.4kg, p<0.001), with LM preserved (-0.05±1.6kg, p=0.805). Muscle strength (4.6-24.7%, p<0.010) and VO2max (3.5±4.7mL·min·kg, p=0.041) significantly improved. Leptin significantly decreased (-2.2[-2.7-0.5]ng/mL, p=0.016) with no other changes in blood biomarkers such as testosterone and lipids (p=0.051-0.765); however, CRP (rs=-0.670, p=0.024) and triglycerides (r=-0.667, p=0.025) were associated with individual changes in LM. CONCLUSION This study shows preliminary efficacy for an exercise and nutrition weight loss intervention to reduce FM, maintain LM, and improve muscle strength and cardiorespiratory fitness in ADT-treated obese PCa patients. The change in body composition may impact blood biomarkers associated with obesity and PCa progression, however, further research is required.