The symptoms of lung cancer metastasis to intestine include: 1. blood in stool, the surface of metastatic tumor is different from normal mucous membrane, which can bleed easily after rubbing with stool. 2. change of defecation habit, the metastatic tumor itself secretes mucus and secondary inflammation changes, not only increase mucus stool, but also stimulate intestinal peristalsis to increase the number of defecation, shapeless stool or thin stool, the lower the intestinal lesion, the more obvious the symptoms, there can be slight abdominal pain before defecation 3. abdominal pain may appear as hidden pain and be ignored. At this time, symptoms such as bowel sounds, abdominal pain, abdominal distension, constipation and difficulty in stool may appear. 6. Systemic symptoms, due to chronic blood loss, cancer ulceration, infection, toxin absorption, etc., patients appear anemia, emaciation, weakness, low fever, etc.