When many rectal cancer patients visit the clinic, the first question is often: Can I preserve my anus? This question is of great concern to the people because it is about the quality of life. And for doctors, it is a more difficult question to answer simply. As a doctor, you have an obligation to explain and interpret your condition to your patients and to communicate smoothly with them. For general patients, the examination in outpatient clinic is divided into 2 main parts: 1. Qualitative examination: i.e. colonoscopy and pathology to confirm whether the patient has rectal cancer or not. 2. 2. Staging examination: Anal preservation depends on many factors, and it depends on the staging of rectal cancer. Staging tests usually include CT, MRI, blood sampling, etc.