Ten percent of people with small intestinal cancers have no symptoms. Most have abdominal pain or distension because of a partial or complete obstruction of the small bowel. There may also be weight loss, nausea and vomiting, fever, change in bowel habits and a general malaise , or weakness that may result from anemia caused by bleeding or malabsorption. The bowel may also become perforated, which can cause acute symptoms. With adenocarcinomas, jaundice may appear when the tumor is in the mid-duodenum, blocking drainage of the common bile duct. Blockage of the bowel may also be caused by what is called pseudolymphoma, a benign overgrowth of the lymph nodes .
