Small Bowel Cancer

Types

The most common forms of small bowel cancer include adenocarcinomas, carcinoid tumors, gastrointestinal stromal tumors (GISTS), lymphomas, and sarcomas. With names derived from the cekks from which they form, these forms of small bowel cancers can occur in any of the three regions of the small intestine: duodenum, jejunum, and ileum. Researchers estimate that more than 5,000 cases of small bowel cancer will be diagnosed this year. Mayo Clinic specialists base treatments on the stage and form of each patient's small bowel cancer.

Adenocarcinomas, the most common small bowel cancers, start on the internal lining of the small bowel, typically in the duodenum.

Carcinoid tumors grow in the cells that produce hormones in the ileum and much less commonly the jejunum and duodenum.

Sarcomas can occur in any part of the small bowel. Several forms of sarcoma occur in the small bowel:

• Gastrointestinal stromal tumors (GIST) develop in any part of the small bowel.
• Leiomyosarcomas grow in the muscle wall of the ileum.
• Rare forms of sarcoma also occur.

Lymphomas develop in the lymph cells (immune system tissue) of the ileum or jejunum, but rarely the duodenum. They are often diagnosed as part of non-Hodgkin's lymphoma.