Common symptoms of bowel cancer include blood in stool, abdominal pain, change of bowel habit and so on. 1. Blood in stool: in the early stage of bowel cancer, the symptom of bloody stool will appear, because the location of lesion is relatively close to anus, and the color of blood is mainly dark red. 2. Abdominal pain: clinically, it is often manifested as abdominal pain, which is mostly seen in right-sided colorectal cancer. The pain mainly manifests as dull pain in the right abdomen, or pain in the right upper abdomen or middle-upper abdomen. 3. Change of defecation habit: when patients have colorectal cancer, the tumor in rectum will produce irritating secretion. The patient will feel urgency and heaviness during defecation, and the frequency of defecation will be increased. At the same time, patients with colorectal cancer will also suffer from intestinal obstruction, anemia, fever and emaciation, etc. At this time, they should consult a doctor in time, and under the guidance of a professional doctor, clarify the cause of the disease and correctly treat it, so as to avoid delaying the condition.