Reasons for Non-reversal of Temporary Stomas After Surgeries of Mid-low Rectal Cancer （NORESTO Study）

The goal of this observational study is to learn about in mid-low rectal patients who received temporary ostomies after surgery of the primary tumors. The main questions it aims to answer are: * To explore the proportion of temporary stomas that cannot be reversed after radical surgery for mid-low rectal cancer and their main causes. * To use the basic information we collected from patients before and during surgery to develop an individualized model for predicting the time of stoma reversal and explore the risk factors affecting stoma reversal.