Lower skeletal muscle index and early complications in patients undergoing radical cystectomy for bladder cancer

BACKGROUND Radical cystectomy (RC) is the standard treatment for patients with muscle-invasive bladder cancer (BC), and it is also a valid option for selected patients with high-risk non-muscle-invasive BC. The purpose of this study was to evaluate the effect on the lower skeletal muscle index (SMI) of short-term postoperative complications of radical cystectomy (RC) in patients with bladder cancer (BC). METHODS A total of 247 patients who received RC for BC and 204 age-matched healthy population-based controls were retrospectively assessed. SMI was measured by preoperative computed tomography scans at the L4 to L5 level. Early complications were graded by Clavien-Dindo classification; severity of grade III or greater was identified as a severe complication. Logistic regression was utilized to determine the relationships between covariables and severe complications. RESULTS A total of 125 (50.61%)/19 (7.69%) patients exhibited overall/severe complications during the early postoperative period. SMI was strongly associated with gender (P <0.01), but not age and body mass index (BMI), among patients with BC. Compared with the matched control group, BC patients exhibited lower SMI. The difference was statistically significant in the subgroup of male patients (P = 0.03). In the multivariate analysis, SMI was an independent predictor of developing severe complications. Each 1 cm²/m² increase in SMI was associated with a decrease in the odds of morbidity by 4.8%. CONCLUSIONS A lower SMI is frequently observed in bladder cancer patients undergoing RC and is shown to be strongly associated with early complications following surgery.