Sigmoid colon cancer in the middle and late colon cancer stage has a better effect if it is actively treated. The prognosis of sigmoid colon cancer depends on the patient’s tumor stage, typing, his/her physique, treatment method and treatment effect, and is judged comprehensively. Therefore, it is difficult to accurately judge the prognosis of a patient only based on the information of middle and late stage of sigmoid colon cancer. If actively treated, the possibility of cure for mid-stage sigmoid colon cancer can even reach 70%-80%; while the 5-year survival rate of advanced sigmoid colon cancer can reach 50% after active and effective treatment. Sigmoid colon cancer is a cancer that occurs in the colon area, which is mainly related to environmental factors, such as long-term dietary fiber insufficiency, smoking, alcohol, obesity, less activity, etc. Some patients have family history, and most of the patients develop the disease after 50 years old. Once sigmoid colon cancer is detected, it is recommended to seek medical treatment as soon as possible and under the guidance of doctors.