Muscle Cross-sectional Area Improves With Home-based Training During Metastatic Castration-resistant Prostate Cancer

Abstract

PURPOSE: Exercise training improves regional body composition in localized prostate cancer, but it is unknown if training has similar effects in advanced disease. Goals of this analysis were to determine changes in leg muscle cross-sectional area (CSA) and quality (MQ) values following home-based exercise training during metastatic castration-resistant prostate cancer (mCRPC) and to compare CSA values to healthy controls (CON). METHODS: Sedentary mCRPC patients undergoing androgen deprivation therapy (ADT) including next generation androgen receptor signaling inhibitors (n = 17, age = 71y ± 8, BMI = 32.0 kg/m2 ± 6.5) underwent CSA and MQ analyses using B-mode ultrasound for the vastus lateralis (VL) muscle before and after a 12-week home-based exercise protocol. Age- and BMI-matched CON (n = 17, age = 69y ± 2, BMI = 32.8kg/m2 ± 6.5) completed baseline scans only. RESULTS: At baseline, VL CSA was lower in mCRPC (9.12cm2+ 3.15) relative to CON (36.55cm2 ± 7.04, p<0.001, d=4.95). For mCRPC patients, the 12-week intervention did not change VL MQ, but increased CSA by 15.2% following the intervention (pre: 8.28cm2 ± 2.85, post: 9.54 ± 3.56, p<0.001, d= 0.39) with no change in MQ. CONCLUSIONS: Patients undergoing ADT for advanced prostate cancer exhibit lower muscle size compared to CON; however preliminary results suggest that home-based exercise training induces a moderate degree of regional muscle hypertrophy. The finding of regional hypertrophy is consistent with work conducted in patients with localized disease on ADT and may be an important outcome to monitor if increases in muscle CSA translate into improvements in physical function and quality of life. Supported by Physical Activity and Cancer Survivorship Pilot Funding.