Small bowel cancer is a rare disease in which malignant (cancer) cells form in the tissues of the small intestine.
The small intestine is part of the body’s digestive system, which also includes the esophagus, stomach, and large intestine. The digestive system removes and processes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) from foods and helps pass waste material out of the body. The small intestine is a long tube that connects the stomach to the large intestine. It folds many times to fit inside the abdomen.
There are five types of small intestine cancer.
The types of cancer found in the small intestine are:
- Carcinoid tumors
- Gastrointestinal stromal tumor
- Lymphoma, including adenocarcinoma and leiomyosarcoma.
- Adenocarcinoma starts in glandular cells in the lining of the small intestine and is the most common type of small intestine cancer. Most of these tumors occur in the part of the small intestine near the stomach. They may grow and block the intestine.
- Leiomyosarcoma starts in the smooth muscle cells of the small intestine. Most of these tumors occur in the part of the small intestine near the large intestine.
Symptoms of Small Bowel Cancer
Possible signs of small bowel cancer include abdominal pain and unexplained weight loss.
These and other symptoms may be caused by small intestine cancer or by other conditions. A doctor should be consulted if any of the following problems occur:
- Pain or cramps in the middle of the abdomen.
- Weight loss with no known reason.
- A lump in the abdomen.
- Blood in the stool.
Diet and health history can affect the risk of developing small intestine cancer.
Risk factors for small bowel cancer include the following:
- Eating a high-fat diet.
- Having Crohn disease.
- Having celiac disease.
- Having familial adenomatous polyposis (FAP).
Stages of Small Bowel Cancer
Staging is used to find out how far the cancer has spread, but treatment decisions are not based on stage. See the General Information section for a description of tests and procedures used to detect, diagnose, and stage small intestine cancer.
There are three ways that cancer spreads in the body.
- Through tissue. Cancer invades the surrounding normal tissue.
- Through the lymph system. Cancer invades the lymph system and travels through the lymph vessels to other places in the body.
- Through the blood. Cancer invades the veins and capillaries and travels through the blood to other places in the body.
When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.
Small bowel cancer is grouped according to whether or not the tumor can be completely removed by surgery.
Treatment depends on whether the tumor can be removed by surgery and if the cancer is being treated as a primary tumor or is metastatic cancer.
Recurrent Small Intestine Cancer
Recurrent small intestine cancer is cancer that has recurred (come back) after it has been treated. The cancer may come back in the small intestine or in other parts of the body.
Tests that examine the small intestine are used to detect, diagnose, and stage small intestine cancer.
Procedures that create pictures of the small intestine and the area around it help diagnose small intestine cancer and show how far the cancer has spread. The process used to find out if cancer cells have spread within and around the small intestine is called staging.
In order to plan treatment, it is important to know the type of small intestine cancer and whether the tumor can be removed by surgery. Tests and procedures to detect, diagnose, and stage small intestine cancer are usually done at the same time. The following tests and procedures may be used:
- Physical exam and history. An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
- Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that produces it.
- Liver function tests: A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by the liver. A higher than normal amount of a substance can be a sign of liver disease that may be caused by small intestine cancer.
- Abdominal x-ray: An x-ray of the organs in the abdomen. An x-ray is a type of energy beam that can go through the body onto film, making a picture of areas inside the body.
- Barium enema: A series of x-rays of the lower gastrointestinal (GI) tract. A liquid that contains barium (a silver-white metallic compound) is put into the rectum. The barium coats the lower gastrointestinal tract and x-rays are taken. This procedure is also called a lower GI series.
- Fecal occult blood test: A test to check stool (solid waste) for blood that can only be seen with a microscope. Small samples of stool are placed on special cards and returned to the doctor or laboratory for testing.
- Upper endoscopy: A procedure to look at the inside of the esophagus, stomach, and duodenum (first part of the small intestine, near the stomach). An endoscope (a thin, lighted tube) is inserted through the mouth and into the esophagus, stomach, and duodenum. Tissue samples may be taken for biopsy.
- Upper GI series with small bowel follow-through: A series of x-rays of the esophagus, stomach, and small bowel. The patient drinks a liquid that contains barium (a silver-white metallic compound). The liquid coats the esophagus, stomach, and small bowel. X-rays are taken at different times as the barium travels through the upper GI tract and small bowel.
- Biopsy: The removal of cells or tissues so they can be viewed under a microscope to check for signs of cancer. This may be done during the endoscopy. The sample is checked by a pathologist to see if it contains cancer cells.
- CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
- Lymph node biopsy: The removal of all or part of a lymph node. A pathologist views the tissue under a microscope to look for cancer cells.
- Laparotomy: A surgical procedure in which an incision (cut) is made in the wall of the abdomen to check the inside of the abdomen for signs of disease. The size of the incision depends on the reason the laparotomy is being done. Sometimes organs are removed or tissue samples are taken for biopsy.
Certain factors affect prognosis (chance of recovery) and treatment options.
The prognosis (chance of recovery) and treatment options depend on the following:
- The type of small intestine cancer.
- Whether the cancer has spread to other places in the body.
- Whether the cancer can be completely removed by surgery.
- Whether the cancer is newly diagnosed or has recurred.