Impact of sarcopenia on kidney function during neoadjuvant chemotherapy and post cystectomy complications in patients treated for localized muscle-invasive bladder cancer.

Abstract

387 Background: Sarcopenia is suspected to influence the complication rates in patients undergoing radical cystectomy. The aim of our study was to assess variations in sarcopenia in patients scheduled for neoadjuvant cisplatin-based chemotherapy (NAC) and radical cystectomy for muscle invasive bladder cancer (MIBC) and to explore the impact of sarcopenia on complications linked to NAC and surgery. Methods: Between January 2012 and December2017, 82 consecutive patients who underwent NAC and RC for cT2-T4 N0 M0 MIBC were retrospectively selected. Using CT scan before and after NAC, Lumbar Skeletal Muscle Index (SMI) was assessed by two observers blinded to patient’s status. We defined severe sarcopenia as SMI < 50 cm2/m2 for men and SMI < 35 cm2/m2 for women. We evaluated pre- and post-NAC cisplatin-based chemotherapy renal function and post-operative complication rates after cystectomy using the Clavien-Dindo classification. We explored risk factors of complications by logistic regression models. Results: According to the SMI cut offs, 47 patients (57.3%) were classified as sarcopenic and 35 patients (42.7%) non-sarcopenic. Patients’ characteristics between sarcopenic and non-sarcopenic patients were not significantly different except for BMI (p < 0.001). Among patients non-sarcopenic before NAC, 9 (19.1%) became sarcopenic after NAC. In multivariate analysis, sarcopenia was an independent significant predictor of renal impairment after NAC (OR 3.01; 95% CI 1.13–8.05; p = 0.02). There was a trend towards a higher rate of stage 3B kidney failure (GFR < 45 mL/min/1.73m2) after NAC in sarcopenic patients (OR 2.79; 95% CI 0.70–11.1) but the difference was not statistically significant (p = 0.14). Moreover, sarcopenia and ASA score were independent significant predictors of postoperative early complications ≤90 days (p = 0.01 and p = 0.02 respectively). Conclusions: We observed significant changes in sarcopenic status during NAC. Sarcopenia, estimated by the lumbar SMI measurement, was an independent predictor associated with the risk of renal impairment during NAC and early postoperative complications after RC.