Does Surgical Resection Improve the Survival of Patients with Gastric Cancer Liver Metastases? A Population-Based, Propensity Score–Adjusted Analysis

Abstract Purpose The use of surgery in the management of patients with gastric cancer liver metastases (GCLM) has been debatable. We aimed to assess whether surgical resection is associated with improved patient survival. Methods Patients with GCLM were identified in the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Adult gastric cancer patients (aged ≥ 18 years) with liver metastases living longer than one month were eligible for this analysis. The overlap weighting method based on lasso regression with penalty factors (OW_pLasso) was applied to reduce the selection bias. The survival times of patients who underwent surgery and those who did not were compared using OW_pLasso adjusted Kaplan-Meier curves and Cox proportional hazards models. Results A total of 3694 patients with GCLM were identified. Of those, 354 (9.58%) patients underwent cancer-directed surgery (CDS). After OW_pLasso adjustment, the median overall survival was 12 months [95% confidence interval (CI) 11–16] in the CDS group and 6 months [95% CI 5–6] in the Non-CDS group. In Cox regression analysis, primary cancer resection was associated with a significantly better overall survival [hazard ratio (HR) 0.562, 95% confidence interval (CI) 0.482–0.656]. The benefit of surgical resection persisted in patients with worse conditions (large size and high-grade tumors, advanced T stages, and limited lymph node metastases). Conclusions In this population-based cohort analysis of patients with gastric cancer and liver metastases, surgical resection was linked to a better overall survival. As a result, surgery has the potential to be an option for treating patients with liver metastases.