FIT: Functional and imaging testing for patients with metastatic cancer.

Abstract

208 Background: Despite multiple cancer cachexia (CC) trials evaluating novel agents, the FDA has not approved a single drug to date. One key challenge in CC trials is selection of endpoints. The aim of this study was to explore changes in body composition and associations with functional and patient-reported outcomes (PROs) to clarify CC trial endpoint selection. Methods: We identified metastatic solid tumor cancer patients receiving cancer-directed therapies at a single cancer center (2016-2018). Patients completed all assessments at study enrollment and 3 months from enrollment. We analyzed body composition utilizing cross-sectional computed tomography (CT) scans at the third lumbar vertebra. Functional assessments included the 6-minute walk test (6MWT), Timed Up-and-Go (TUG) test, and Short Physical Performance Battery (SPPB). PROs included the Functional Assessment of Anorexia/Cachexia Therapy (FAACT) and Functional Assessment of Cancer Therapy Fatigue (FACT-F). We examined changes in body composition and functional assessments from enrollment to 3 months using paired t-tests. We utilized linear regression models to assess the relationship between changes in body composition and changes in functional assessment adjusting for age and sex. Results: A total of 57 patients completed baseline assessments; 19 patients did not complete 3-month assessments (5 died, 1 hospice, 13 withdrew). Of the 38 patients with complete data (mean age 61.8 years, 47% female, 71% GI malignancy), 50% received chemotherapy, 16% immunotherapy, and 34% combination therapy. From enrollment to 3 months, we observed an increase in total adipose tissue (16.9±52.4 cm2, 95% CI -33.79-0.63; p = 0.059), but not weight or skeletal muscle. Greater losses in skeletal muscle were associated with greater declines in 6MWT (B = 0.036, p = 0.014) and SBBP (B = 2.444, p = 0.002), but not the TUG. We observed no association with change in weight with all functional outcomes or PROs. Moreover, we found no association with body composition and PROs from enrollment to 3 months. Conclusions: In future CC trials, changes in longitudinal body composition rather than weight should be utilized. Furthermore, changes in skeletal muscle and the 6MWT and/or SBBP may be preferred endpoints.