Impact of sarcopenia on outcomes of patients treated with trimodal therapy for muscle invasive bladder cancer

Abstract

Objective: We sought to investigate the incidence of sarcopenia and its impact on main oncological outcomes in patients with muscle invasive bladder cancer (MIBC) treated with trimodal therapy (TMT).

Patients and methods: This was a retrospective analysis of 141 MIBC patients treated with TMT in the period 2002 to 2018. Sarcopenia was identified through pretreatment computed tomography scans and defined as a skeletal muscle index of <55 cm²/m² for men and <39 cm²/m² for women. Body mass index (BMI)-adjusted definition of sarcopenia was used to evaluate for sarcopenic obesity. Uni- and multivariable analyses were performed to assess the impact of sarcopenia on initial complete response and overall survival (OS) to TMT.

Results: Median age at diagnosis was 73 years [range: 65-81] and median follow up was 32 months (Inter Quartile Range: 18-66). Median OS was 67 months (95% CI: 53-83). The incidence of sarcopenia and BMI-adjusted sarcopenia was 56.7% and 40.4%, respectively. On multivariable analysis, Eastern Cooperative Oncology Group performance status (HR = 2.37, 95% CI: 2.1-5.67, P = 0.001) and complete response to treatment (HR = 0.26, 95% CI: 0.14-0.049, P = 0.001] were independently associated with improved OS. Sarcopenia and BMI-adjusted sarcopenia were not independently associated with either complete response to TMT or OS. Similarly, in a subpopulation of 74 patients considered fit for radical cystectomy, we found that neither sarcopenia (P = 0.49) nor BMI-adjusted sarcopenia (P = 0.22) had an impact on OS.

Conclusion: Sarcopenia and BMI-adjusted sarcopenia are prevalent in patients with MIBC undergoing TMT. TMT is a suitable treatment modality for patients with MIBC irrespective of their sarcopenia status.

Keywords: Bladder cancer; Chemoradiation; Sarcopenia; Trimodal therapy; Urothelial cancer.