Small Intestine Cancer

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Our integrated care team provides comprehensive treatment plans to give you the best chance for a cure. Call 888-662-8252 to learn more about our gastrointestinal oncology services.

Small intestine cancer, also called small bowel cancer, is the rarest type of GI cancer. The UCLA Gastrointestinal Oncology Program includes a group of experts in all types of gastrointestinal (GI) cancer, including small intestine cancer.

With precise diagnosis and leading-edge treatment, we can offer the best outcome to people with one of these uncommon tumors. Our doctors study innovative treatments through advanced clinical trials. We also deliver therapies such as hyperthermic intraperitoneal chemoperfusion (HIPEC) for metastatic small bowel cancer (cancer that has spread) in the abdomen.

What Is Small Intestine Cancer?

The small intestine is the largest part of the GI tract, the tube that processes food into waste. Cancer can develop anywhere in the GI tract, from the esophagus (swallowing tube) through the rectum, which stores waste before you eliminate it.

There are four types of small intestine cancers:

  • Carcinoid tumors: The most common type of small intestine cancer is a carcinoid tumor. These tumors, which tend to grow slowly, are a type of neuroendocrine tumor.
  • Adenocarcinoma: About one-third of small bowel cancers are adenocarcinoma. These tumors start in the cells that line the intestine.
  • Sarcoma: These tumors begin in muscle or other connective tissues. Gastrointestinal stromal tumors (GIST) and leiomyosarcoma are types of sarcoma.
  • Lymphoma: Cancers that start in the lymphocytes, a type of immune cells, are called lymphoma.

What Causes Small Intestine Cancer?

Doctors aren’t yet sure what causes most cases of small intestine cancer. People may have higher risk if they have:

  • Inherited syndromes like Lynch syndrome, familial adenomatous polyposis (FAP) or Peutz-Jeghers syndrome (PJS)
  • Intestinal problems such as celiac disease or Crohn’s disease
  • Previous colon cancer
  • Cystic fibrosis

What Are the Symptoms of Small Intestine Cancer?

The first symptoms of small intestine cancer are usually vague. The most common symptom is pain, sometimes with nausea or vomiting. Symptoms are usually worse after eating. Other symptoms include:

  • Feeling tired or weak
  • Losing weight unintentionally
  • Dark stools from internal bleeding
  • Anemia (low red blood cell count)
  • Jaundice (a yellow tint to the skin and eyes)

How Is Small Intestine Cancer Diagnosed?

Because small intestine cancer is uncommon, it requires expertise for a precise diagnosis. Doctors will ask about your symptoms and study several tests to diagnose a tumor. Your diagnostic tests may include:

  • Blood tests: Blood samples can show signs of infection or changes in your liver function. The results tell your doctors which further tests may be useful.
  • Endoscopy: Endoscopy looks inside your GI tract for abnormal areas. During some types of endoscopy, UCLA’s advanced endoscopists can remove suspicious polyps or cells. Read more about interventional endoscopy.
  • Biopsy: Your doctor performs a biopsy to remove a small sample of cells for laboratory study and analysis. If the cells are cancerous, your doctor will recommend the best course of treatment. Meet our doctors.
  • Imaging: Specialized imaging tests can identify cancerous cells (lesions) in your intestinal tract. Your doctor may order X-rays, CT scans or MRI scans to help understand a tumor’s location and type. Learn more about our imaging technology.

How Is Small Intestine Cancer Treated?

Small intestine cancer treatment usually involves surgery. After surgeons remove the tumor, you may need follow-up care including radiation or chemotherapy. Your treatment options may include:

Tumor resection

In some cases, surgeons can remove the tumor cells and a small margin of cells around the tumor. Your surgeon may need to remove a section of the small intestine to eliminate the cancer. After removing the tumor, your doctor will reconnect the remaining sections of the intestine (anastomosis).

Bypass surgery

Some tumors cannot be removed surgically. Over time, they may block the intestine. Your surgeon may create a bypass that allows food to go around the tumor in the small intestine.

Radiation therapy

After surgery, your doctor may recommend radiation therapy, which uses powerful X-rays to destroy cancer cells. Advanced forms of radiation therapy shape radiation beams to the tumor to reduce damage to delicate intestinal tissues. Read more about radiation oncology.


UCLA is one of only a few centers in the region to provide intraperitoneal chemoperfusion. Your surgeon may recommend HIPEC if cancer cells have metastasized to the abdominal cavity. This specialized treatment bathes the abdominal cavity in a chemotherapy solution immediately after surgery to destroy as many cancer cells as possible.

Biologic treatments

Through clinical trials, UCLA doctors offer several new small bowel cancer therapies that aren’t widely available. Researchers are studying biologic treatments, or immunotherapies, that use the body’s immune system to fight small intestine cancer. Some doctors also work with radiosensitizers, drugs that make cancer cells more sensitive to radiation therapy. See our clinical trials.

Targeted therapy for GISTs

Targeted therapy blocks gene changes in gastrointestinal stromal tumors to prevent cancer from growing. These drugs are often the first treatment for GISTs, and they may work for GISTs when chemotherapy does not. You may have targeted therapy before or after surgery, or to improve your quality of life when surgery can’t remove a tumor completely.

Contact Us

To schedule an appointment with the UCLA Gastrointestinal Oncology Program, please call the UCLA Cancer Hotline at 888-ONC-UCLA (888-662-8252) Monday through Friday, 9am to 5pm, or our Physician Referral Service at 1-800-UCLA-MD1 (310-825-2631).