Abstract: Objective To investigate the predisposing factors carried out in patients with secondary primary esophageal cancer and the related factors affecting its prognosis.Methods Patients with pathologically definite esophageal cancer diagnosis from 2000~2019 in the Surveillance/Epidemiology and End Results (SEER) database were selected,from which the data of patients with other malignancies as the first and esophageal cancer as the second primary (Secondary Primary Esophageal cancer-SPE) were screened,and logistic regression was used to analyze the independent risk factors in patients with secondary primary esophageal cancer,and the independent risk factors affecting the prognosis of such patients were analyzed by Cox proportional hazard model.Results A total of 13520 patients with multiple primary malignancies with esophageal cancer,including a total of 8308 patients with secondary primary esophageal cancer.Multiple logistic analysis showed that age,tumor site,tumor differentiation,pathological examines,SEER neoplasm invasiveness and regional lymph node adoption were independent factors influencing the occurrence of SPE,while multiple Cox risk proportion analysis suggested that age,year of diagnosis,race,tumor differentiation,SEER neoplasm invasiveness,surgery,chemotherapy,radiotherapy,and triple therapy were independent risk factors influencing SPE.Conclusion This study identified risk factors for secondary primary esophageal cancer,and surgery may be an effective treatment for SPE,which clinicians can use as a reference for diagnosis and treatment.

Key words: secondary primary esophageal cancer, surveillance/epidemiology and end results database, prognosis