Overview Small bowel, or small intestine, 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.
Tumor Types The types of cancer found in the small intestine are adenocarcinoma, sarcoma, carcinoid tumors, gastrointestinal stromal tumor, and lymphoma. This summary discusses adenocarcinoma and leiomyosarcoma (a type of sarcoma).
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 These and other symptoms may be caused by small intestine cancer or by other conditions. Consult a doctor 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.
Treatment Different types of treatments are available for patients with small intestine cancer. Some treatments are standard (the currently used treatment, often referred to as “standard of care”), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.
Three types of standard treatment are used:
Surgery Surgery is the most common treatment of small intestine cancer. One of the following types of surgery may be done:
• Resection: Surgery to remove part or all of an organ that contains cancer. The resection may include the small intestine and nearby organs (if the cancer has spread). The doctor may remove the section of the small intestine that contains cancer and perform an anastomosis (joining the cut ends of the intestine together). The doctor will usually remove lymph nodes near the small intestine and examine them under a microscope to see whether they contain cancer. • Bypass: Surgery to allow food in the small intestine to go around (bypass) a tumor that is blocking the intestine but cannot be removed.
Even if the doctor removes all the cancer that can be seen at the time of the surgery, some patients may be given radiation therapy after surgery to kill any cancer cells that are left. Treatment given after the surgery, to lower the risk that the cancer will come back, is called adjuvant therapy.
Radiation therapy Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.
Chemotherapy Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.