Muscle wasting, visceral and subcutaneous adiposity, inflammation, nutritional deficiencies, and metastatic esophageal cancer (MEC) prognosis.

Abstract

e14595 Background: MEC, associated with fatigue and dysphagia, leads to loss of skeletal muscle mass, malnutrition, subcutaneous and visceral adiposity. Cancer inflammation mobilizes muscle and adipose tissue, potentially leading to cachexia and sarcopenia. Supportive management depends on understanding the cancer frailty determinants that lead to poor outcomes. Methods: We retrospectively identified de novo MEC patients pts treated in Toronto, Canada (2007-2014). Body composition including visceral (VA) and subcutaneous adiposity (SA) at L3 level were assessed with baseline CT scans using SliceOMatic software by two outcome-blinded radiologists (Intraclass correlation, 0.92-1.00). Sarcopenia was assessed using Skeletal Muscle Index (SMI) with cut-offs defined either by optimized-stratification (OpS) or gender-dependent consensus cutoffs (GdC). Cox proportional hazard models generated adjusted hazard ratios (aHR). Results: Of 101 patients, 82% were male; 96% Caucasian; median age at diagnosis 61y (29-88); mean body mass index (BMI) 25.4; 69%/31% adeno/squamous cell carcinoma; median overall and progression free survival were: 6.4 (OS) and 3.9 mos (PFS). Median follow-up time was 5.6 mos. SMI-OpS and SMI-GdC were correlated (Rho = 0.67). Nutritional risk index, BMI, neutrophil-to-lymphocyte and neutrophil-to-platelet ratios were not associated with outcome (p > 0.20, each comparison). However, univariable analyses identified serum albumin, LDH, and either SMI-OpS or SMI-GdC as being associated with OS. In multivariable models, sarcopenia was associated with worse OS (SMI-OpS aHR = 1.93 (1.0-3.7) p = 0.046; SMI-GdC aHR = 2.30 (1.3-4.1) p = 0.004), and worse PFS (SMI-OpS aHR = 2.16 (1.2-4.0) p = 0.01; SMI-GdC aHR = 1.66 (1.0-2.9) p = 0.07)). In 55 pts receiving chemotherapy at diagnosis, less VA (p = 0.01) and SA (p = 0.02), as continuous variables, were associated with worse OS. Conclusions: Though no associations were found between nutritional deficiencies or inflammatory markers and prognosis, there was approximately a two-fold worse prognosis in the presence of sarcopenia, and associations with loss of adiposity. (JB/AFF/DR/MM contributed equally).