487 Background: Patients with GU cancers experience declines in physical function and QOL during treatment. Exercise may improve QOL, potentially by reducing fatigue. We evaluated whether adherence to a remote exercise program improves QOL, if fatigue mediates this effect, and whether treatment type or cancer subtype influences outcomes. Methods: Patients with metastatic prostate, bladder, or kidney cancer initiating systemic therapy were assessed at baseline (T1) and after 12 weeks (T2) using FACT-G (0-108). Fatigue was assessed on a 0-5 scale. Participants joined a remote exercise program (3-5 h/week, resistance + aerobic) via Vedius platform. Adherence was categorized as moderate-to-high (≥6 weeks) or low (≤5 weeks). Linear mixed models evaluated FACT-G over time, including treatment type, cancer group, and interactions. Mediation analysis assessed whether fatigue changes from T1 to T2 mediated exercise adherence effects on FACT-G. Results: Seventy-five patients were recruited (median age 71, 81% male, 47% college educated). Cancer types: prostate 47% (chemotherapy 85%, ± hormonal blockade 57%), kidney 37% (immunotherapy 67%, combination regimens 18%, tyrosine kinase inhibitors 15%), bladder 16% (chemotherapy 58%, antibody-drug conjugate 42%). FACT-G showed no significant effects by cancer type or treatment. Adherence predicted larger fatigue reductions (B=-1.36, p<0.001). Fatigue changes predicted FACT-G at T2 (B=-2.18, p=0.02). The direct effect of adherence on FACT-G was not significant (B=2.57, p=0.41), but the indirect effect through fatigue was significant (effect=2.98, BootSE=1.48, 95% CI 1.08, 5.79), indicating that improvements in QOL with exercise are mediated by fatigue reduction. Conclusions: Participation in a remote exercise program was associated with improved QOL in patients with metastatic GU cancers, primarily through reductions in fatigue. These benefits were observed across cancer types and treatment modalities, highlighting the value of structured exercise interventions as an integral component of supportive care in this population. Exercise adherence, fatigue change, and quality of life. Analysis Predictor Outcome B / F SE t / df p-value 95% CI Linear Mixed Model Treatment Type FACT-G - - F(3,8)=0.62 0.624 - GU Cancer Group FACT-G - - F(2,8)=0.98 0.415 - FACT-G T1 FACT-G - - F(29,8)=2.76 0.068 - FACT-G × Treatment FACT-G - - F(7,8)=1.69 0.238 - FACT-G × GU Group FACT-G - - F(4,8)=0.86 0.525 - Mediation Analysis Exercise Adherence Fatigue -1.36 0.27 -5.06 <0.001 -1.90, -0.83 Fatigue Change FACT-G -2.18 1.23 -1.78 0.020 -4.64, -0.27 Direct Effect (Adherence → FACT-G) FACT-G 2.57 3.12 0.82 0.41 -3.66, 8.79 Indirect Effect via Fatigue FACT-G <jats:td co
Bergerot et al. (Sun,) studied this question.