Novel use of computed tomography-derived body composition to facilitate risk assessment in patients with bladder cancer.

BACKGROUND: Comprehensive geriatric assessments (CGA) inform risk stratification in bladder cancer (BC) care but are time- and resource-intensive. PURPOSE: To investigate whether body composition analysis (BCA) on computed tomography (CT) is associated with CGA. METHODS: Patients with BC (any stage) were enrolled in a prospective observational cohort study between September 2020 and July 2021. Patients completed CGA, including grip strength (GS), Timed Up and Go (TUG), and Clinical Frailty Scale. BCA was derived from staging CT at vertebral levels T12 and L3, including cross-sectional area (CSA) and density of skeletal muscle (SM), subcutaneous adipose tissue (SAT), and intermuscular adipose tissue (IMAT). Generalized linear models were used to assess associations between BCA and GS, TUG, and frailty. RESULTS: Amongst 56 patients (median age 71 years; 84% male), increased SM CSA and density at T12 and L3 were associated with lower odds of abnormally low GS (L3: odds ratio [OR] 0.73; 95% confidence interval [CI]: 0.57, 0.94; P = 0.02, and OR 0.65; 95% CI: 0.44, 0.94; P = 0.002, respectively). Increased SM density at T12 and decreased IMAT CSA at T12 and L3 were associated with lower odds of abnormally low TUG (T12: OR 0.58; 95% CI: 0.37, 0.89; P = 0.01, and OR 4.24; 95% CI: 1.31, 13.70; P = 0.02). There was insufficient evidence of an association between BCA and frailty. CONCLUSIONS: BCA at T12 and L3 is associated with CGA components GS and TUG. These findings support future investigation of predictive ability of CT-derived biomarkers, including their potential use as surrogates for selected CGA components and their ability to facilitate guideline-concordant risk stratification.