Risk Factors Analysis of Long-term Prognosis in Patients with D2 Radical Surgery for Stage Ⅲ Gastric Cancer after Adjuvant Chemoradiotherapy: Based on the Data of 10-year Follow-up

Background Locally advanced gastric cancer mainly includes stage Ⅲ gastric cancer, which is mainly treated with comprehensive therapy. Postoperative recurrence is a key factor affecting the prognosis of patients. Objective To explore the influencing factors of long-term prognosis in patients with stage Ⅲ gastric cancer undergoing D2 radical surgery and adjuvant chemotherapy. Methods Gastric cancer patients who underwent D2 radical surgery and adjuvant chemoradiotherapy were collected from the Department of Radiotherapy at Zhongshan Hospital affiliated to Fudan University from 2009 to 2014. They were pathologically diagnosed with stage Ⅲ gastric cancer according to the International Union of Cancer (UICC) and American Cancer Federation (AJCC) 8th edition TNM staging system for gastric cancer. All postoperative patients were followed up every 3 months in the first year, every 6 months for the following 2 years, and once a year thereafter. The deadline for follow-up is December 15, 2021. Survival rates of subgroups were compared using Log-rank tests.The influencing factors of overall survival (OS) and disease-free survival (DFS) were compared using Cox proportional hazards regression analysis, and the prediction of clinicopathological features were analyzed by Nomogram. Comparison of survival differences among patients with different pTNM stagings, age, metastatic lymph node radios (LNR), and gastrectomy methods using Kaplan-Meier method. Results A total of 135 qualified patients were included, with a median follow-up time of 10.48 years. Within 5 years, there were 70 cases of recurrence and 62 deaths. The 5-year DFS rate and OS rate were 48.1% (65/135) and 54.1% (73/135), respectively; Within 10 years, there were 74 cases of recurrence and 74 deaths. The 10-year DFS rate nd OS rate were both 45.2% (61/135). The Log-rank test results showed that there was a statistically significant difference in 5-year survival rates among patients with different pTNM stagings, pT stagings, LNRs, cancer nodules, tumor locations, and gastrectomy methods (P50%, OS: HR=1.74, 95%CI=1.03-2.94; DFS: HR=1.73, 95%CI=1.02-2.94), and gastrectomy method (total gastrectomy, OS: HR=2.07, 95%CI=1.22-3.50; DFS: HR=2.02, 95%CI=1.20-3.41) were independent influencing factors for OS and DFS in patients with stageⅢ gastric cancer undergoing D2 radical surgery with adjuvant chemotherapy (P