Non-alcoholic Fatty Liver Is A Risk Factor For Liver Metastasis In Patients With Non-small Cell Lung Cancer

Background:Non-small cell lung cancer(NSCLC)is one of the malignant tumors with high incidence in human beings.Liver is the common site of blood metastasis of lung cancer,among which 38%?44%patients may have liver metastasis.Patients with liver metastases develop rapidly.Compared with other distant metastases,the efficacy of chemotherapy for liver metastases is poor and the survival period is short.Most patients die within 7 month NAFLD.Therefore,liver metastasis is an important factor affecting the prognosis of NSCLC.In order to prolong the overall survival of NSCLC patients,it is important to explore the risk factors of liver metastasis of NSCLC so as to implement medical intervention.However,to date,no studies have investigated the impact of NAFLD on liver metastasis in patients with non-small cell lung cancer(NSCLC).Therefore,we designed this two-center cohort study to observe whether liver metastasis in patients with non-metastatic non-small cell lung cancer could be affected by NAFLD.Methods:Patients who underwent treatment for NSCLC at two affiliated hospitals of Southern Medical University,between January 1,2005 and December 31,2015,were retrospectively reviewed.NSCLC patients were divided into the study and control groups based on the presence of NAFLD,examined by abdominal ultrasound.Thefollow-up duration was calculated from the day of pathological biopsy to the day of liver metastasis,or to the last liver imaging.Liver metastasis-free survival(LMS)and distant metastasis-free survival(DMS)were calculated using the Kaplan-Meier method,multivariable analysis was performed using a Cox proportional hazards regression model.The clinical pathological features of patients between the two groups were compared.The effect of NAFLD on liver metastasis and overall metastasis was evaluated,adjusting for other confounders using Cox regression analyses.A p value<0.05 was used to determine statistical significance and all p values were based on 2-sided tests.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 NAFLD(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(NAFLD)group(hazard ratio(HR)(1.42;95%CI 1.03-1.96;P=0.031).Multivariate regression analysis demonstrated that NAFLD was an independent risk factor for liver metastasis HR(1.43;95%CI 1.02-2.01;P=0.039).However,NAFLD was not associated with overall metastasis of NSCLC HR(0.99;95%CI 0.84-1.17;P=0.895).Conclusion:NAFLD was an independent predictor of liver metastasis from in patients with NSCLC.