Age-specific impact on the survival of gastric cancer patients with distant metastasis: an analysis of SEER database

Abstract

The age-specific impact on the survival of gastric cancer patients with distant metastasis is still unclear. In this study, we identified 11, 299 gastric cancer patients with distant metastasis between 2004 and 2013 from Surveillance, Epidemiology, and End Results population-based dataset. Patients were divided into young (≤60) and elderly groups (>60). Kaplan-Meier methods and multivariable Cox regression were used for the analysis of long-term survival outcomes and risk factors. There were significant differences between the two groups in terms of race, primary site, grade, histologic type, surgery, marital status and clinical T stage (P<0.05). The 1- and 3-year cancer specific survival rates were 29.0% and 6.2% in young group and 22.8% and 4.8% in elderly group in both univariate (X²=116.430, P<0.001) and multivariate analysis (P<0.001). Young patients had significantly better 1- and 3-year cancer specific survival than elderly patients in each T stage. Age was further validated as an independent survival factor in all T stages (T1, T2, T3, T4 and T_X, P<0.05). In conclusion, age was an independent prognostic factor for gastric cancer patients with distant metastasis.

Keywords: age; distant metastasis; gastric cancer; survival.

Figure 1. Survival curves in GC patients with M1 of different primary site, surgical treatment, marital status and T stage

(A) Primary site. X² = 162.320, P<0.001; (B) Surgery. X² = 313.299, P<0.001; (C) Marital status. X² = 119.561, P<0.001; (D) T stage. X² =252.356, P<0.001.

Figure 2. Survival curves in GC patients with M1 of different age

(A) All patients. Young group vs. Elderly group, X² = 116.430, P<0.001; (B) T1 stage. Young group vs. Elderly group, X²= 9.817, P=0.002; (C) T2 stage. Young group vs. Elderly group, X² = 20.034, P<0.001; (D) T3 stage. Young group vs. Elderly group, X² = 8.278, P=0.004; (E) T4 stage. Young group vs. Elderly group, X² = 22.753, P<0.001; (F) Tx stage. Young group vs. Elderly group, X² = 51.779, P<0.001.