This page was reviewed under our medical and editorial policy by
Maurie Markman, MD, President, Medicine & Science
This page was updated on May 20, 2022.
Tumors in the small intestine may block the flow of food and affect digestion. As the tumor gets bigger, the blockages may cause pain in the abdomen. A slowly bleeding tumor may lead to anemia. Digested blood may cause the stool to become black or tarry. An obstruction—when the flow of food is completely blocked—may cause intense pain, nausea and vomiting and typically requires immediate surgery.
In general, however, intestinal cancer symptoms are often vague and difficult to diagnose.
Some common symptoms of cancer that develops in the small intestines include:
Common symptoms of intestinal cancer may be confused with colorectal or anal cancer symptoms. In addition, small intestine cancer symptoms may be signs of other conditions or gastrointestinal diseases.
Often, however, small tumors may not cause any apparent symptoms. Sometimes the cancer may be found by chance during another unrelated procedure or surgery.
Slow-growing types of cancer, like carcinoid tumors, may take years to find and diagnose.
Next topic: What are the types of intestinal cancer?
