Inverse association between age and risk of lymph node metastasis in patients with early gastric cancer: a surveillance, epidemiology, and end results analysis.

Recent studies have shown that young patients with gastric cancer are at a more advanced stage and have poor survival, but the cause is still unclear. The prognosis of gastric cancer is closely related to LNM, but the relationship between age and LNM in early gastric cancer (EGC) is currently unclear. Therefore, we aimed to study the relationship between age and the risk of LNM in EGC. We screened out patients with EGC who underwent surgery from the SEER research database from 1975 to 2016, and retrospectively analyzed the proportion of LNM in different age groups. We grouped age into 18-39, 40-49, 50-59, 60-69, 70-79, and ≥ 80 years old, and used univariate analysis and multivariate logistic regression to analyze the correlation between age and LNM. We included 9231 patients with EGC, with LNM rates of 20.3%, 23.3%, 21.0%, 19.8%, 18.1%, and 13.2% in the age groups of 18-39 years old (2.3%), 40-49 (6.1%), 50-59 years old (15.7%), 60-69 years old (24.8%), 70-79 years old (27.2%) and ≥80 years old (23.9%), respectively. We found that when older than 39 years old, the risk of LNM and postoperative survival time of EGC patients decrease (<0.001). Multivariate analysis results showed that age, tumor size, the number of retrieved lymph nodes (rN), tumor grade, and tumor location were related to LNM. This study found that age in patients with EGC was inversely related to the risk of LNM, and positively correlated with postoperative survival. For older patients with EGC, endoscopic treatment is more appropriate. For young patients with EGC, LNM should be considered when choosing endoscopic treatment.