There are different kinds of tumors that can arise in the small intestine, although cancer of this organ is far less common than colorectal cancer. Symptoms can be similar to those of any gastrointestinal malignancy and include weight loss, abdominal pain or cramps, a mass or lump in the abdomen, and blood in the stool. Other symptoms and signs can include nausea, vomiting, and intestinal obstruction or perforation.

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