Abstract: Background and purpose: Esophageal cancer is one of the common malignant tumors in China, and it ranks in the top ten among all cancers in terms of morbidity and mortality. To date, there are few articles reporting the survival status of esophageal cancer patient and its related risk factors in Chongqing. The aim of this study was to analyze the survival of esophageal cancer patients who had special medical insurance in Chongqing in order to provide clinical evidence for evaluation of prognosis and prevention in the future. Methods: The retrospective cohort study was conducted, and a total of 1 622 patients with esophageal cancer were enrolled from Jan. 2000 to Dec. 2018 in the Chongqing Malignant Tumor Treatment System. Observation indicators included demographic characteristics (age, gender, ethnicity, marriage, occupation), clinical treatment and pathological examination (surgery, pathological type, TNM staging), results of patient follow-up (survival status) and analysis of prognostic factors. Follow-up by telephone were implemented among out-patients. The endpoint was the patient's death, and follow-up time was until Dec. 31, 2018. The measurement data were described as x±s, and the counting data were expressed as absolute number (%); survival rate was calculated using Kaplan-Meier method; log-rank test was used for single factor analysis. The Cox proportional hazards regression model was used for multivariate analysis, and survival curves were plotted using GraphPad Prism 8.0. Results: The demographic characteristics of 1 622 patients with esophageal cancer were: 28-99 years old, with an average age of (65.37±9.99) years; 1 425 male patients (87.25%); 1 601 Han patients (98.71%); 1 529 married patients (94.27%). The number of patient whose occupation was enterprise unit and/or worker was large, with 473 cases (29.16%). Results of clinical treatment and pathology showed that 741 patients received surgical treatment (45.68%), and the most common pathological type of the patients was squamous cell carcinoma with about 1 272 cases (83.68%). A total of 1 042 patients had clinical stages, 758 of which were Ⅲ-Ⅳ (72.74%), and 511 patients (82.82%) had highly differentiated cancer. Follow-up results indicated 1 289 cases (79.47%) were followed up. The median survival time was 20.57 months (95% CI: 18.31-22.83), and the 1-, 3-, and 5-year observed survival rates were 65.22%, 37.14%, 26.93%, respectively. Univariate analysis showed that there were statistically significant differences in survival prognosis among groups of age, marital status, infiltration depth (T), positive lymph node (N), distant metastasis (M), clinical stage and operation and prognosis. There was no significant difference in survival prognosis among patients with different gender, nationality, occupation and degree of tissue differentiation. Multivariate analysis demonstrated that surgery, depth of infiltration (T) and presence of positive lymph nodes (N) were independent risk factors for the survival and prognosis of these esophageal cancer patients. Conclusion: The prognosis of esophageal cancer was poor, and it was affected by many factors. Among these factors, surgical treatment and depth of invasion (T ₁ -T ₂ and T ₃ ) were protective factors.

Key words: Esophageal cancer, Special disease patients, Survival follow-up, Observed survival rate, Prognosis