If there are symptoms, the following may indicate colon cancer: 1  Abdominal pain and tenderness in the lower abdomen. 2  Blood in the stool. 3  Diarrhea, constipation, or other change in bowel habits. 4  Narrow stools. 5  Weight loss with no known reason.
Diarrhea may be caused by: lactose intolerance. bacterial infection. damage to intestinal wall. hormone-producing tumors (including certain types of pancreatic neuroendocrine tumors) inflammation or ulceration of the bowel. malabsorption caused by surgery that has shortened the intestines. pancreatic enzyme insufficiency.
Diarrhea: Very common after surgery: Many patients have diarrhea after surgery. This is caused by a lack of pancreatic enzymes which affects digestion. Adjuvant chemotherapy may aggravate pre-existing diarrhea. Medication to replace pancreatic enzymes taken with meals and possibly dietary changes. Depression: Common