Diseases & Conditions

Adenocarcinoma of the Small Intestine

Overview, Causes, & Risk Factors

Adenocarcinoma of the small intestine is a form of cancer that occurs in the part of the intestine that descends from the stomach. It is a rare form of cancer.

What is going on in the body?

The small intestine plays a key role in the digestion of foods. Many nutrients are absorbed by the small intestine as food passes through it. Adenocarcinoma occurs in the tissues that line the small intestine. It causes the cells in these tissues to grow and multiply out of control. These cells form a tumor along the wall of the intestine. This tumor then begins to invade the tissues around it.

In time, the tumor will grow through the intestinal wall. The tumor then goes on to invade structures around the intestine. Cancer cells can break off from the tumor and metastasize. This means the cancer is spread through the bloodstream. Cancer cells can also spread through the system that drains into lymph nodes.

What are the causes and risks of the disease?

The risk factors for this type of cancer are not well defined. Diet may play a role, especially a diet high in nitrates. Some other risk factors may include:

  • celiac disease, in which the body is unable to absorb certain foods
  • Crohn disease, an inflammation of the bowel
  • a history of adenocarcinoma elsewhere in the body
  • a history of colorectal cancer
  • immunodeficiency disorders that lead to a weakened immune system
  • inherited gastrointestinal syndromes
  • older age

  • Symptoms & Signs

    What are the signs and symptoms of the disease?

    Adenocarcinoma of the small intestine generally causes vague symptoms. In some cases, symptoms may not occur until the tumor is large and blocks part or all of the small intestine. Some symptoms include:

  • abdominal pain after meals
  • anemia, which is a low red blood cell count
  • nausea
  • The person can have symptoms from specific organ damage if the cancer has metastasized.

    Diagnosis & Tests

    How is the disease diagnosed?

    Diagnosis of adenocarcinoma begins with a medical history and physical exam. An upper GI X-ray study will usually show a mass pressing on the intestine. A small tube called an endoscope can be passed into the intestine to help view the mass. The tube has a light and a camera on the end of it. This allows the doctor to see the inside of the intestine.

    A small piece of the mass is removed and examined. This small sample is called a biopsy. This biopsy helps to confirm that the mass is cancerous.

    Prevention & Expectations

    What can be done to prevent the disease?

    There is no known way to prevent adenocarcinoma of the intestine.

    What are the long-term effects of the disease?

    Adenocarcinoma of the small intestine is fatal if it is not treated with success.

    What are the risks to others?

    Adenocarcinoma poses no risk to others.

    Treatment & Monitoring

    What are the treatments for the disease?

    The primary treatment for adenocarcinoma of the small intestine is surgery. The doctor operates to remove the tumor and the affected part of the intestine. Tissue near the tumor, including lymph nodes, will also be removed. Often, this may be the only treatment.

    What are the side effects of the treatments?

    Surgery can cause bleeding, infection, or allergic reaction to anesthesia. Removing a part of the small intestine may cause food to pass too quickly through the digestive system. The person may have diarrhea and cramping. Nutrients present in the food cannot be well absorbed if the food passes through too quickly. Without a healthy diet, the person may become malnourished and lose weight.

    What happens after treatment for the disease?

    Many times, adenocarcinoma of the intestine is until the disease is a late stage. The cancer may have already metastasized to other organs. If the cancer comes back or gets worse, chemotherapy may help to improve the person's quality of life. Once this type of cancer spreads beyond the small intestine, it cannot be cured.

    How is the disease monitored?

    The person will be monitored closely using abdominal CT scans and special X-rays to check if the cancer has come back or spread. Any new or worsening symptoms should be reported to the doctor.


    Author:Miriam P. Rogers, EdD, RN, AOCN, CNS
    Date Written:
    Editor:Crist, Gayle P., MS, BA
    Edit Date:07/22/02
    Reviewer:Kathleen A. MacNaughton, RN, BSN
    Date Reviewed:10/07/02


    Goit, D.G (1997) Cancer of the small intestine in Cancer: Principle and Practice of Oncology. 5th Edition DeVita, V.T. (ed). J.B. Lippincott: Philadelphia. Pp. 1128-1143