Non-alcoholic fatty liver disease and colorectal cancer survival.

Purpose: Liver diseases including non-alcoholic fatty liver disease (NAFLD) and ensuing alterations to the micro-environment may affect development of liver metastasis. Mirroring the rise in obesity rates, prevalence of NAFLD is increasing globally. Our objective was to examine the association between NAFLD and mortality in colorectal cancer patients.

Methods: Colorectal Cancer-Sarcopenia and Near-term Survival (C-SCANS) is a retrospective cohort study which included 3,262 stage I-III patients, aged 18-80 years, and diagnosed between 2006 and 2011 at Kaiser Permanente Northern California. Cox proportional hazards regression was used to calculate multivariable adjusted hazard ratios (HR) and 95% confidence intervals (CI).

Results: After up to 10 years of follow-up, 879 deaths, including 451 from CRC were identified. Cases diagnosed with NAFLD before and within 1 month after CRC diagnosis (pre-existing NAFLD; n = 83) had a HR of 1.64 (95% CI 1.06-2.54) for overall and a HR of 1.85 (95% CI 1.03-3.30) for CRC-specific mortality compared to those without NAFLD. Findings did not differ significantly by sex, stage, tumor location, and smoking status, and were also similar when restricted to obese patients only.

Conclusions: Independent of body mass index and prognostic indicators, CRC patients with pre-existing NAFLD had a worse prognosis than those without NAFLD.