Sarcopenia as a Predictive Factor for Response to Upfront Cisplatin-Based Chemotherapy in Patients with Muscle-Invasive Urothelial Bladder Cancer.

<bold>Purpose:</bold> We hypothesized sarcopenia as predictive factor as a response to upfront chemotherapy of muscle-invasive urothelial bladder cancer (MIBC). <bold>Methods:</bold> We retrospectively studied 30 patients who received upfront cisplatin-based chemotherapy for MIBC (pT2–4 N0/+ M0) before planned radical cystectomy. Skeletal muscle index (SMI) was calculated by CT at study baseline and following completion of chemotherapy. Patients were stratified according to the presence of sarcopenia. Endpoints included clinical and pathological response. <bold>Results:</bold> Sixteen of the 30 patients (53.3%) had sarcopenia at baseline. The median SMI was 51.2 cm2/m2 (IQR 45.6–57.9). Throughout the course of chemotherapy, 22 patients (73.3%) experienced a decline in SMI, which ranged from 1 to 20% (median decline 3%, p < 0.01). All 16 patients with baseline sarcopenia persisted, while 5 of 14 patients (35.7%) without baseline sarcopenia became sarcopenic (p = 0.06). None of the clinical variables were predictive of clinical or pathological response, including SMI (p = 0.78 and p = 0.59), sarcopenia (p = 0.65 and p = 0.16) and SMI kinetics (p = 0.54 and p = 0.77). <bold>Conclusion:</bold> Sarcopenia is present in a considerable proportion of patients with MIBC undergoing upfront cisplatin-based chemotherapy before planned RC. SMI decreases during treatment, but neither baseline SMI nor its kinetics is associated with response to chemotherapy. [ABSTRACT FROM AUTHOR]