Sarcopenia as a marker to assess the surveillance necessity after a 5-year cancer-free period in patients who undergo radical cystectomy: A multi-institutional retrospective study.

Abstract

871 Background: Although continuous surveillance after a 5-year cancer-free period in patients with bladder cancer (BC) who undergo radical cystectomy (RC) is recommended, optimal candidates for continuous surveillance remain unclear. Sarcopenia is associated with unfavorable prognosis in various malignancies. Thus, we hypothesized that sarcopenia, characterized by low muscle quantity, might be a useful marker to assess the necessity of surveillance after a 5-year cancer-free period in patients who underwent RC. Methods: This multi-institutional retrospective study included 274 patients with muscle-invasive bladder cancer (MIBC) who had a 5-year cancer-free period after RC. Muscle quantity was evaluated using the psoas muscle index (PMI) using computed tomography images five years after RC. The optimal cut-off values for all-cause mortality were calculated separately for men and women using receiver operating characteristic curves. Patients with lower PMI values than the cut-off values were diagnosed with sarcopenia. Recurrence-free survival (RFS) and overall survival (OS) after a 5-year cancer-free period were evaluated using the Kaplan–Meier method and compared using the log-rank test. Moreover, univariable and multivariable Cox proportional hazards regression analyses were performed to evaluate the impact of sarcopenia on OS. Results: The median age and follow-up period after the 5-year cancer-free period were 73 years and 63 months, respectively. Of the 274 patients, 129 (47%) were diagnosed with sarcopenia five years after RC. By the end of the follow-up period after the 5-year cancer-free period, 14 (5.1%) and 77 (28%) patients experienced recurrence and died from any cause, respectively. The 10-year RFS rate was 93%. RFS was not significantly different between the two groups, whereas OS in the sarcopenia group was significantly shorter than that in the non-sarcopenia group. After adjustment for confounding variables, sarcopenia was significantly associated with shorter OS (Table). Conclusions: Patients with sarcopenia might not need continuous surveillance after a 5-year cancer-free period, considering the high mortality rate. Multivariable analysis for OS. Factor P value Hazard ratio 95% CI Age Continuous <0.001 1.065 1.027–1.105 Performance status Continuous 0.012 1.829 1.145–2.922 Hypertension Positive 0.011 1.897 1.157–3.110 eGFR Continuous 0.168 0.990 0.976–1.004 Urinary diversion Neobladder 0.033 0.546 0.313–0.953 Sarcopenia Positive 0.025 1.801 1.076–3.012