Is sarcopenia and sarcopenic obesity associated with clinical and pathological outcomes in patients undergoing radical nephroureterectomy?

PURPOSE: To investigate the association between sarcopenia and sarcopenic obesity on clinical, perioperative, and oncologic outcomes in patients with upper-tract urothelial carcinoma (UTUC) undergoing radical nephroureterectomy (RNU). METHODS: Retrospective review of our institutional UTUC database was performed to identify all patients who underwent radical nephroureterectomy from 2002-2016. Skeletal Muscle Index (SMI) was measured at the L3 vertebral level and standardized according to patient height (cm2/m2). Sarcopenia was defined as<55cm2/m2 for men and<39cm2/m2 for women. Sarcopenic obesity was also assessed in patients with BMI>30kg/m2. Unadjusted logistic regression and Wilcoxon rank sum tests examined the relationship between sarcopenia and variables. RESULTS: A total of 100 patients (66 men and 34 women) with a mean age of 68 years, BMI of 30, Charlson comorbidity index of 4.0, tumor size of 3.5, and SMI of 50.8cm2/m2 were included. Furthermore, 42 patients (42%) were sarcopenic, and 18 patients (18%) had sarcopenic obesity. Median EBL was 150ml, OR duration was 322 minutes, and length of stay was 5.0 days. Sarcopenia was associated with several clinical factors including decreasing BMI, male sex, and coronary artery disease, albeit without association with any perioperative or oncologic outcomes. Sarcopenic obesity was similarly associated with several clinical variables including male sex, diabetes mellitus, hyperlipidemia, as well as increased EBL (P = 0.047) and non-bladder cancer disease relapse (P = 0.049). CONCLUSIONS: This contemporary cohort of patients undergoing RNU highlights the association of nonmodifiable risk factors with sarcopenia and disease relapse with sarcopenic obesity. Larger studies are necessary to further validate these observations.