What are the oral chemotherapeutic drugs for rectal cancer? Rectal cancer, the occurrence of this disease is not harmful to patients, it is also a common malignant tumor in the anorectal department. Clinical diagnosis is not so easy. Chemotherapy is a common method for treating the disease. So, what are the oral chemotherapy drugs for rectal cancer?

　　I. Capecitabine

　　Capecitabine is an oral fluorouracil It can be converted into 5-FU by thymidine phosphorylase (TP), which is highly expressed in tumor tissues. Using the characteristics of higher TP activity in tumor tissues than normal tissues, the purpose of selective intratumoral activation is achieved, thereby maximizing tumor killing effect and reducing damage to normal human cells. At the same time, the twice-daily administration mode can simulate the continuous infusion of 5-FU to provide steady-state blood drug concentration at the site of drug action.

　　Second, oxaliplatin

　　oxaliplatin is a new third-generation platinum-based chemotherapy drug, which is the same as other platinum-based drugs. DNA is the site of action. Platinum atoms form intra- and inter-chain cross-links with DNA chains, blocking DNA replication and transcription. Oxaliplatin binds faster with DNA and has a certain effect on RNA.

　　Three. Irinotecan

　　Irinotecan is a semi-synthetic derivative of natural camptothecin, which acts as a cell by inhibiting topoisomerase Toxic effect. It can selectively act on topoisomerase Ⅰ, has a very important intervention function on the process of DNA spatial configuration, replication, recombination, transcription and mitosis, breaks DNA single and double strands, thereby inducing cancer cell apoptosis.

　　Four, bevacizumab

　　bevacizumab is a 149-KD recombinant human monoclonal IgG1 against VEGF-A antibody. It can selectively bind VEGF in circulating blood, prevent VEGF from binding to receptors on cell membranes, inhibit microangiogenesis, limit the blood supply of tumor cells, reduce tissue interstitial pressure, increase vascular permeability, accelerate the delivery of chemotherapy drugs, and promote tumors Apoptosis of endothelial cells.

　　 generally should be highly vigilant in patients with stool hemorrhage clinically, do not rashly diagnosed as "dysentery", "internal hemorrhoids", etc., must be further checked to rule out the possibility of cancer. For the early diagnosis of rectal cancer, we must pay attention to the application of digital rectal examination, rectal endoscopy or sigmoidoscopy.