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Palliative Gastrectomy and Survival in Patients With Metastatic Gastric Cancer: A Propensity Score-Matched Analysis
Qin Li1, Jiahua Zou2, Mingfang Jia3
1Cancer Center, Renmin Hospital of Wuhan University, Wuhan, China.
Objectives:
The role of palliative gastrectomy in the management of metastatic gastric cancer remains inadequately clarified.
Methods:
We analyzed patients with metastatic gastric cancer enrolled in the Surveillance, Epidemiology, and End Results registry from January 2004 to December 2012. Propensity score (PS) analysis with 1:1 matching and the nearest neighbor matching method was performed to ensure well-balanced characteristics of the groups of patients who undergone gastrectomy and those without gastrectomy. Data were analyzed by Kaplan-Meier and Cox proportional hazards regression models to evaluate the overall survival and cancer-specific survival rates with corresponding 95% confidence intervals (CIs).
Results:
In general, receiving any kind of gastrectomy was associated with an improvement in survival in the multivariate analyses (hazard ratio [HR]os = 0.64, 95% CI = 0.59-0.70, HRcss = 0.63, 95% CI = 0.57-0.68) and PS matching (PSM) analyses (HRos = 0.63, 95% CI = 0.56-0.70, HRcss = 0.62, 95% CI = 0.55-0.70). After PSM, palliative gastrectomy was found to be associated with remarkably improved survival for patients with stage M1 with only 1 metastasis but not associated with survival of patients with stage M1 with extensive metastasis (≥2 metastatic sites).
Discussion:
The results obtained from the Surveillance, Epidemiology, and End Results database suggest that patients with metastatic gastric cancer might benefit from palliative gastrectomy on the basis of chemotherapy. However, a PSM cohort study of this kind still has a strong selection bias and cannot replace a properly conducted randomized controlled trial.
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