Small-Intestine Cancer

(Cancer of the Small Intestine)

ByAnthony Villano, MD, Fox Chase Cancer Center
Reviewed/Revised May 2025
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  • Blood in the stool is a common symptom, but sometimes the cancer blocks the intestine, causing crampy abdominal pain and vomiting.

  • The diagnosis is based on various intestinal viewing techniques, including enteroclysis, endoscopy, and barium x-rays.

  • Surgical removal is the best form of treatment.

Cancer of the small intestine is uncommon in the United States, occurring in about 12,440 people and causing about 2,090 deaths each year.

Adenocarcinoma is the most common type of cancer of the small intestine. Adenocarcinomas develop in the glandular cells of the lining of the small intestine. People with Crohn disease of the small intestine are more likely than others to develop adenocarcinoma.

Rare types of small-intestine cancer

Gastrointestinal neuroendocrine tumors (also called carcinoid tumors) can develop in the glandular cells that line the small intestine. Gastrointestinal neuroendocrine tumors often secrete hormones that cause diarrhea and flushing of the skin. These tumors are most commonly identified in the small intestine, followed by the appendix, stomach, and rectum. Treatment of these tumors depends on where they originate in the small intestine as well as the location of any sites to which cancer cells may have spread in a process known as metastasis. The liver is the most common site of metastasis.

Some gastrointestinal neuroendocrine tumors can be removed surgically. Tumors that have spread can be controlled with a medication, such as octreotide or everolimus, or with a treatment that involves the use of a radioactive Some gastrointestinal neuroendocrine tumors can be removed surgically. Tumors that have spread can be controlled with a medication, such as octreotide or everolimus, or with a treatment that involves the use of a radioactivesomatostatin analog given by vein (this is called peptide receptor radioligand therapy or PRRT).

Lymphoma (cancer of the lymphatic system) may develop in the middle section (jejunum) or the lower section (ileum) of the small intestine. Lymphoma may cause a segment of intestine to become rigid or elongated. This cancer is more common among people with untreated celiac disease. Treatment depends on the type of lymphoma and may include chemotherapy and radiation therapy to help control symptoms and sometimes lengthen survival time.

Leiomyosarcoma (cancer of smooth muscle cells) can develop in the wall of the small intestine. Chemotherapy may slightly lengthen survival time after surgery to remove leiomyosarcomas.

Kaposi sarcoma is a type of skin cancer that can affect internal organs and sometimes occurs in people with late-stage human immunodeficiency virus (HIV) infection. Kaposi sarcoma can occur anywhere in the digestive tract but usually in the stomach, small intestine, or colon. This cancer usually does not cause symptoms in the digestive tract, but bleeding, diarrhea, and intussusception (one segment of the intestine slides into another, much like the parts of a telescope) may occur. Treatment of Kaposi sarcoma depends on where the cancer is but may include surgery, chemotherapy, and radiation therapy.

Symptoms of Small-Intestine Cancer

Adenocarcinoma may cause bleeding into the intestine, which shows up as blood in the stool, and obstruction, which in turn may lead to crampy abdominal pain, expansion (distention) of the abdomen, and vomiting.

Sometimes cancers of the small intestine cause intussusception (when one part of the intestine telescopes into an adjacent part).

Diagnosis of Small-Intestine Cancer

  • Enteroclysis

  • Endoscopy

  • Video capsule endoscopy

Doctors typically do enteroclysis. In this procedure, a large amount of barium liquid is inserted through a tube in the nose and x-rays are taken as the barium moves through the digestive tract. Sometimes this procedure is done with a computed tomography (CT) scan instead of plain x-rays, in which case the person can just drink the barium rather than having a tube put through their nose.

For endoscopy, a doctor passes an endoscope (a flexible viewing tube) through the mouth and down to the duodenum and part of the jejunum (the upper and middle sections of the small intestine) to locate the tumor and do a biopsy (remove a tissue sample for examination under a microscope). A doctor can sometimes see tumors of the ileum (the lower section of the small intestine) by passing a colonoscope (an endoscope used to view the lower part of the digestive tract) through the anus, through the entire large intestine, and up into the ileum.

A wireless battery-powered capsule that contains 1 or 2 small cameras (video capsule endoscopy) can be swallowed to take pictures of tumors of the small intestine.

Sometimes exploratory surgery is needed to identify a tumor in the small intestine.

Treatment of Small-Intestine Cancer

  • Surgical removal

The best treatment for most types of cancerous tumors in the small intestine is surgical removal of the tumor.

If doctors are able to see the tumor with an endoscope, they may also remove it by applying an electrical current (electrocautery), heat (thermal obliteration), or high-energy beam of light at the tumor (laser phototherapy).

Chemotherapy and radiation therapy after surgery do not lengthen survival time.

Drugs Mentioned In This Article

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