I. What is colorectal cancer? There are often inquiries about colorectal cancer from patients, so today we will talk about the problem of colorectal cancer. The colon is divided into colon and rectum, so colon cancer and rectal cancer are both called colorectal cancer, and the standard name for professionals should be “colorectal cancer”. Colorectal cancer is a kind of digestive system tumor with high incidence, but compared with liver cancer, pancreatic cancer and gastric cancer, its prognosis is better, if found early and without distant metastasis, it can often survive for many years, so it must be treated regularly. Second, about the surgical treatment of colorectal cancer: Early colorectal cancer can be treated minimally invasively under endoscopy, but colorectal cancer often has no manifestation in the early stage of its development, and when it is seen for symptoms such as blood in stool and intestinal obstruction, it is often in the middle and late stage, which is why most colorectal cancers often need surgical treatment when they are found, and some more advanced patients with distant metastasis even lose the chance of surgery, and the purpose of surgery is often just to relieve obstruction and other symptoms. The purpose of surgery is often just to relieve obstruction and other conditions. Therefore, surgery is often the first choice for colorectal cancer, and those who can be operated should be treated surgically as much as possible. For rectal cancer, if it is too close to the anus, it is impossible to keep the anus, and it is necessary to bring a fecal bag. Third, about chemotherapy for colorectal cancer: Except for early colorectal cancer, most intestinal cancers, even if completely removed by surgery and without lymph node metastasis, may have micro-metastases invisible to the naked eye, therefore, chemotherapy is necessary after surgery, that is, to help kill those invisible cancer cells. It should be noted that this process is just like weeding with a harvester, the grass is removed and sometimes the seedlings are also pulled up, which is why chemotherapy has side effects, nausea, and bone marrow suppression (mainly manifested as a drop in white blood cells). Targeted therapy is equivalent to manual weeding, which is directed to pull up the seedlings, and the damage to the seedlings is small, but the force is limited, so it can only selectively weed, and its efficacy is also selective. Regarding the selection of chemotherapy drugs, fortunately than other tumors, there are standard chemotherapy regimens for colorectal cancer, and these regimens have been well proven in the clinical process. Several important regimens are as follows: 1. FORFOX regimen, a regimen based on oxaliplatin (also called platinum oxalate) and 5-fluorouracil, is the preferred regimen after surgery; 2. Selox regimen, a regimen based on oxaliplatin and Siroda, has basically the same efficacy as the first regimen, and if the patient is very weak and cannot tolerate chemotherapy, Siroda alone can be used, but the effect is less effective; 3. FOLFIRI is an irinotecan and 5-fluorouracil-based regimen, mainly used for patients with inoperable mid- to late-stage tumors; 4. If liver metastases have occurred, the combination of bevacizumab or cetuximab should be considered. The course of treatment should be at least six months, and the tumor should be evaluated during the drug administration. IV. Medicine is a complex science and disease treatment is a scientific process: Several issues should be emphasized in the treatment of colorectal cancer, which are also frequently asked by patients: 1. Tumors should be removed as much as possible; 2. Medium and advanced tumors must be combined with adjuvant chemotherapy after surgery, excluding Chinese medicine, which is not chemotherapy; 3. Chemotherapy must be evaluated during chemotherapy and should be reviewed regularly to monitor disease recurrence; 4. What indicators: during chemotherapy, blood routine, tumor markers, liver and kidney function should be checked. After the result of chemotherapy, it is necessary to review colonoscopy, CT, and tumor markers regularly. It should be emphasized with you that the treatment of any disease is a very complicated issue, to be guided by doctors, the bias prescriptions, experience exchange of patients can not be trusted, often there are patients hope to give a specific medication program on the Internet, Chinese medicine to see, smell, ask, cut, Western medicine to see, touch, tap, listen, said to be and patients full communication, otherwise, direct medication is very dangerous.