It is not scientific to say that “the small intestine is not cancerous”, but the small intestine is also at risk of cancer, which generally refers to primary small bowel cancer. Primary small bowel cancer is relatively rare, and its incidence is 1% of gastrointestinal tumors. The disease is related to adenomatous polyps, and smoking, Crohn’s disease and other diseases will increase the incidence of small bowel cancer, and common types of small bowel cancer include adenocarcinoma, carcinoid tumor, sarcoma, etc. The symptoms are not obvious at first, and as the disease progresses, it may become cancerous. The symptoms of small bowel cancer are not obvious at first, and as the disease progresses, abdominal pain, nausea, weight loss, pyloric obstruction, gastrointestinal bleeding, anemia and other symptoms may appear. When uncomfortable symptoms appear in the body, it is recommended to go to the hospital in time, under the guidance of physicians to conduct relevant examinations, and carry out relevant treatments after clarifying the cause of the disease.