The association of body composition with postoperative complications and length of hospital stay after radical or partial nephrectomy in patients with renal cell cancer: a multicenter population-based cohort study

Abstract

Background: Body mass index (BMI) and body composition have been associated with postoperative outcomes in oncological surgery. Evidence in renal cell cancer (RCC) is limited and inconsistent. Therefore, we examined BMI and body composition in relation to postoperative outcomes in patients with RCC.Methods: We conducted a multicenter population-based historical cohort study including 801 patients with RCC treated with radical (79%) or partial (21%) nephrectomy between 2008-2012. Computed Tomography images at third lumbar vertebrae were assessed for skeletal muscle (SM) index, SM density, visceral adipose tissue (VAT) index and subcutaneous adipose tissue index (SATI). Multivariable multilevel logistic regression analyses were used to examine associations between BMI, body composition and (major) postoperative complications and extended length of hospital stay (LOHS) (≥7 days). Discrimination of models for major complications was compared using receiver operating characteristics (ROC) curves.Results: In total, 19.6% of the patients had postoperative complications (6.2% Clavien grade ≥III) and 24.1% had extended LOHS. A 10-unit increase in SM density was inversely associated with extended LOHS [odds ratio (OR) 0.58; 95% confidence interval (95% CI): 0.44-0.78]. Associations of high BMI and lower SM density with risk of major complications and of higher VAT index with extended LOHS were also observed but statistical significance differed according to surgical procedure. Models predicting major complications with or without body composition parameters were not different.Conclusions: Lower SM density was associated with extended LOHS and non-significantly associated with higher risk of major postoperative complications. High BMI was associated with higher risk of major postoperative complications. Higher VAT was non-significantly associated with higher risk of extended LOHS. Results by surgical procedure were in the same direction but were only statistically significant for some subgroups. Validation of these results and investigation of the added value of body composition parameters to anatomic classification systems is needed.

Predicting adverse outcomes in oncological nephrectomy: let’s take a look at the patient around the tumor

“…Still, the present study (7) connects with previous research on locally advanced (22), and cytoreductive nephrectomy (23) to suggest a possible role for CT-based body composition analysis in subgroups with such an elevated risk that it becomes clinically significant. Patients with vena cava thrombus, metastatic disease, and those >80 years old are at particular risk of adverse outcomes, for whom we often hesitate to propose surgery.…”

“…The present study (7) adds to the existing evidence by showing increased LOS in patients with low SMD. Interestingly, low SMD was associated with major complications in subgroups of patients undergoing radical (but not partial), and laparoscopic/ robot-assisted (but not open) nephrectomy (7).…”

“…The lack of significant association between SAT, and especially visceral adipose tissue with complications in this (7) and previous studies (11,18) leaves the value of this marker to be determined. Accordingly, skeletal muscle and adipose tissue indexes failed to improve the accuracy of a model based on established predictors of major complications [age, stage, and American Society of Anesthesiologists (ASA) score] as reported by Maurits et al (7).…”

“…The lack of significant association between SAT, and especially visceral adipose tissue with complications in this (7) and previous studies (11,18) leaves the value of this marker to be determined. Accordingly, skeletal muscle and adipose tissue indexes failed to improve the accuracy of a model based on established predictors of major complications [age, stage, and American Society of Anesthesiologists (ASA) score] as reported by Maurits et al (7). In their series, 78% of patients undergoing radical nephrectomy harbored a pT1 tumor, suggesting that the utility of CT-based body composition analysis in the general RCC population RCC is limited by its heterogeneity and the low number of major complications in the study population.…”

“…The study presented by Maurits et al ( 7 ) on this issue of Translational Andrology and Urology addresses the equally important, and less investigated, determinant of nephrectomy outcomes: patient features. More specifically, they investigated whether body composition variables—skeletal muscle density (SMD), body mass index (BMI), and adipose tissue distribution—impact on postoperative morbidity of RCC patients.…”