Fatty liver is a risk factor for liver metastasis in Chinese patients with non-small cell lung cancer

BACKGROUND: The hepatic microenvironment, which may include chronic inflammation and fibrosis, is considered to contribute to the development of liver metastases. Hepatic steatosis (HS) might cause liver inflammation and fibrosis. However, to date, no studies have investigated the impact of HS on liver metastasis in patients with non-small cell lung cancer (NSCLC). METHODS: A retrospective cohort study was performed on patients who received NSCLC treatment at two hospitals affiliated with the Southern Medical University from January 2005 to December 2015. The patients were grouped according to the presence of HS. The clinicopathological features of patients between the two groups were compared. The effect of HS on liver metastasis and overall metastasis was evaluated, adjusting for other confounders using Cox regression analyses. RESULTS: In total, 1,873 patients with NSCLC with no distant metastases were included in this study, and 408 (21.8%) patients were diagnosed with HS (at the time of diagnosis or before diagnosis). Liver metastases occurred in 166 (8.9%) patients. Liver metastasis-free survival was significantly worse in the study (HS) group (hazard ratio (HR) 1.42; (95% CI [1.03–1.96]); P = 0.031). Multivariate regression analysis demonstrated that HS was an independent risk factor for liver metastasis (HR 1.43; 95% CI [1.02–2.01]; P = 0.039). However, HS was not associated with overall metastasis of NSCLC (HR 0.99; 95% CI [0.84–1.17]; P = 0.895). CONCLUSION: Hepatic steatosis was an independent predictor of liver metastasis from in patients with NSCLC.