Sarcopenia and systemic inflammation are associated with decreased survival after cytoreductive nephrectomy for metastatic renal cell carcinoma

Abstract

BACKGROUND:This study was aimed at assessing the associations of sarcopenia, muscle density, adiposity, and inflammation with overall survival (OS) after cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma. METHODS: In all, 158 patients undergoing CN from 2001 to 2014 had digitized preoperative imaging for tissue segmentation via Slice-O-Matic software (version 5.0) at the mid-L3 level. The skeletal muscle index was calculated with the skeletal muscle area (cm 2 ) normalized for height (m 2 ), and the skeletal muscle density (SMD) was calculated with average Hounsfield units. Adiposity was measured with the cross-sectional area (cm 2 ) of visceral, subcutaneous, and intramuscular adiposity compartments and was similarly normalized for height. The average fat density was obtained in Hounsfield units. OS was estimated with the Kaplan-Meier method. Associations between body composition, inflammation metrics, and relevant clinicopathology and OS were assessed with univariable and multivariate Cox analyses. RESULTS: Seventy-six of the 158 patients (48%) were sarcopenic. Sarcopenia was associated with elevated neutrophil to lymphocyte ratios (NLRs; P = .02), increased age (P = .001), lower body mass indices (P = .009), greater modified Motzer scores (P = .019), and lower SMD (P = .006). The median OS was 15.0 and 29.4 months for sarcopenic and nonsarcopenic patients, respectively (P = .04). Elevated inflammation (NLR or C-reactive protein), in addition to sarcopenia, was independently associated with OS, with an elevated NLR ≥ 3.5 and sarcopenia associated with the poorest OS at 10.2 months. No associations were observed between measurements of muscle density or adiposity and OS. CONCLUSIONS: Sarcopenia and measures of high systemic inflammation are additively associated with inferior OS after CN and may be of use in preoperative risk stratification.

Prognostic significance of sarcopenia and systemic inflammation for patients with renal cell carcinoma following nephrectomy

“…BMI has previously been regarded as a prognostic indicator of tumors. In this paper, sarcopenia was found associated with a low BMI, while multivariable analysis revealed that BMI was not an independent predictor for OS, which was in agreement with prior studies examining BMI and RCC ( 15 , 22 ). However, a recent research pointed out that longer survival occurred in patients with higher BMI, and it was restricted to males, but not to females ( 23 ).…”

“…( 14 ) found the combined utility of sarcopenia and the elevated mGPS for predicting reduced survival and earlier recurrence in patients with localized RCC. Sarcopenia with elevated NLR or CRP as a negative predictor of OS after cytoreductive nephrectomy in metastatic RCC was later investigated ( 15 ). Similarly, the poor prognostic effects of sarcopenia and NLR in colorectal cancer ( 11 ), as well as sarcopenia and LMR in gastric cancer ( 13 ) have explored.…”

“…Moreover, the combination of sarcopenia and inflammation could lead to worse prognosis of malignant tumors (11)(12)(13). In RCC studies, sarcopenia with elevated inflammation, e.g., the modified Glasgow Prognostic Score (mGPS), neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP), was investigated for predicting inferior overall survival (OS) (14,15). Although systemic inflammation was proved to be associated with sarcopenia risk in RCC patients of China (16), the combined impact of these two factors on survival have not been well explored yet.…”

Data regarding covariates significantly associated with sarcopenia and varying albumin statuses in patients with renal cell carcinoma

“…Preoperative axial CT and MRI images were segmented at the mid-L3 vertebral level as previously described. [ 1 , 2 ] Imaging segmentation was completed by 4 trained observers following training requiring <1% inter-observer and intra-observer variability. Each observer was blinded to patient history and outcomes.…”

“…Image processing was completed using Slice-O-Matic software (version 5.0; Tomovision) using predesignated thresholds for skeletal muscle (-29 to +150 Hounsfield units for CT and region growing tool for MRI). [1] , [2] , [3] , [4] Skeletal muscle area (SMA) in cm 2 was determined by measuring the combined surface area of the psoas, quadratus lumborum, erector spinae, transversus abdominis, internal oblique, external oblique, and rectus abdominis. Skeletal muscle index (SMI; cm 2 /m 2 ) was calculated by normalizing the SMA by height in meters squared.…”