Abstract:Objective: To investigate the clinical factors affecting the prognosis of elderly patients with advanced gastric cancer. Methods: SEER*Stat software was used to extract patients with advanced gastric cancer aged 65-85 years with pathological diagnosis from 2010 to 2016.The univariate and multivariate Cox regression analysis were used to investigate the clinical factors affecting the prognosis of elderly patients with advanced gastric cancer. Results: Cox multivariate regression showed that the HR for 75-85 years was 1.33 (95%CI=1.20-1.49, P=0.000); the HR for middle and high differentiation was 0.82 (95%CI=0.71-0.93, P=0.003), and 0.61 (95%CI=0.43-0.86, P=0.005); HR of tumor size in 31-60 mm, 61-90 mm, ≥91 mm were 1.16 (95%CI=1.01-1.33, P=0.035), 1.2 (95%CI=1.01-1.42, P=0.035), and 1.53 (95%CI=1.26-1.85, P=0.000). With the increase of LNR, the HR also increased (P≤0.001); the HR of bone metastases was 1.4 (95%CI=1.08-1.81, P=0.01), and the HR of multiple metastatic sites was 1.54 (95%CI=1.30-1.83, P=0.000); and the HR for multiple primary cancer was 0.66 (95%CI=0.48-0.92, P=0.013). Conclusion: Independent prognostic factors affecting advanced gastric cancer in the elderly include age, degree of differentiation, tumor size, LNR, number of tumors, and metastatic sites. However, because LNR information and access are dependent on the implementation of surgery, but the proportion of advanced gastric cancer surgery is low, so it’s practical application value in the prognosis prediction of advanced gastric cancer is debatable.