It is possible for some bowel cancer patients to continue to live for more than 20 years as they strengthen their immune system and slow down the spread of cancer cells by exercising more and supplementing nutrition. From relevant news reports and clinical studies, we can learn that cancer has the possibility of self-healing, but the probability is relatively low. The principle of cancer self-healing is mainly related to the function of the immune system in the patient’s body. If the patient’s immunity is strengthened under the action of certain factors, such as proper exercise, supplemental nutrition, and happy mood, the patient’s own immune system can kill the cancer cells. Delaying the development and deterioration of the disease, it is possible to survive for more than 20 years without treatment. The probability of cancer self-healing is relatively too low, patients with bowel cancer still need to receive regular medical treatment such as surgery, radiotherapy, chemotherapy and other treatments, in order to effectively slow down the development of the disease, and must not take it lightly, so as not to cause delay in their condition.