Data were collected from the electronic medical records of Xijing Hospital. Each record is entered by two team members working simultaneously to ensure data accuracy.
The goal of this observational study is to learn about in describe participant population. The main questions it aims to answer are:~What are the risk factors of postoperative pulmonary infection in patients with esophageal cancer？~Whether we could establish a clinical prediction model to provide basis for early clinical intervention or not? Participants will describe the main tasks participants will be asked to do, treatments they'll be given and use bullets if it is more than 2 items. If there is a comparison group: Researchers will compare insert groups to see if insert effects.