Clinicopathological features and prognostic significance of site-specific metastasis in gastric cancer: a population-based, propensity score-matched analysis.

Abstract

Objective: Distant metastasis complicates gastric cancer management and worsens patient outcomes. Understanding the clinicopathological characteristics and prognostic impact of site-specific metastases is crucial for improving treatment strategies and survival prediction.

Methods: Data from 8338 metastatic gastric cancer patients (2010-2015) were retrieved from the SEER database. Patients were categorized by metastatic organ involvement. Chi-square tests analyzed clinicopathological differences. Cancer-specific survival (CSS) was assessed using Kaplan-Meier curves and the log-rank test. Independent prognostic factors were identified through Cox regression analysis. Propensity score matching minimized group heterogeneity.

Results: The liver was the most common metastatic site (43.20%). Patients with bone, brain, or lung metastases had significantly shorter CSS compared to those without these metastases. CSS differences between liver metastasis and non-metastasis were not significant. Propensity score matching confirmed shorter CSS in patients with bone and lung metastases. Single-site metastasis had a better prognosis than multiple-site metastasis, with liver-only metastasis showing the best survival and bone-only metastasis the worst. Multivariate Cox regression identified bone, brain, and lung metastases, age, histology, tumor grade, T stage, N stage, primary tumor resection, and chemotherapy as independent prognostic factors.

Conclusions: The metastatic site significantly influences the prognosis of gastric cancer. Single-site metastasis offers a survival advantage over multiple-site involvement, with liver metastasis showing a better prognosis and bone metastasis the worst. These findings emphasize the importance of site-specific management and the prognostic value of metastatic patterns in gastric cancer.