Stomach Cancer

Like all other organs of the body, the stomach is made up of many types of cells. Normally, cells divide to produce more cells only when the body needs them. This orderly process helps keep us healthy.

Stomach cancer (also called gastric cancer) can develop in any part of the stomach and may spread throughout the stomach and to other organs. It may grow along the stomach wall into the esophagus or small intestine.

Stomach Cancer Picture

It also may extend through the stomach wall and spread to nearby lymph nodes and to organs such as the liver, pancreas, and colon. Stomach cancer also may spread to distant organs, such as the lungs, the lymph nodes above the collar bone, and the ovaries.

When cancer spreads to another part of the body, the new tumor has the same kind of abnormal cells and the same name as the primary tumor. For example, if stomach cancer spreads to the liver, the cancer cells in the liver are stomach cancer cells. The disease is metastatic stomach cancer (it is not liver cancer). However, when stomach cancer spreads to an ovary, the tumor in the ovary is called a Krukenberg tumor. (This tumor, named for a doctor, is not a different disease; it is metastatic stomach cancer. The cancer cells in a Krukenberg tumor are stomach cancer cells, the same as the cancer cells in the primary tumor.)

Stomach cancer can be hard to find early. Often there are no symptoms in the early stages and, in many cases, the cancer has spread before it is found. When symptoms do occur, they are often so vague that the person ignores them. Stomach cancer can cause the following:

• Indigestion or a burning sensation (heartburn);
• Discomfort or pain in the abdomen;
• Nausea and vomiting;
• Diarrhea or constipation;
• Bloating of the stomach after meals;
• Loss of appetite;
• Weakness and fatigue; and
• Bleeding (vomiting blood or having blood in the stool).

Any of these symptoms may be caused by cancer or by other, less serious health problems, such as a stomach virus or an ulcer. Only a doctor can tell the cause. People who have any of these symptoms should see their doctor. They may be referred to a gastroenterologist, a doctor who specializes in diagnosing and treating digestive problems. These doctors are sometimes called gastrointestinal (or GI) specialists.

Cancer of the stomach is difficult to cure unless it is found in an early stage (before it has begun to spread). Unfortunately, because early stomach cancer causes few symptoms, the disease is usually advanced when the diagnosis is made. However, advanced stomach cancer can be treated and the symptoms can be relieved. Treatment for stomach cancer may include surgery, chemotherapy, and/or radiation therapy. New treatment approaches such as biological therapy and improved ways of using current methods are being studied in clinical trials. A patient may have one form of treatment or a combination of treatments.

Surgery is the most common treatment for stomach cancer. The operation is called gastrectomy. The surgeon removes part (subtotal or partial gastrectomy) or all (total gastrectomy) of the stomach, as well as some of the tissue around the stomach. After a subtotal gastrectomy, the doctor connects the remaining part of the stomach to the esophagus or the small intestine. After a total gastrectomy, the doctor connects the esophagus directly to the small intestine. Because cancer can spread through the lymphatic system, lymph nodes near the tumor are often removed during surgery so that the pathologist can check them for cancer cells. If cancer cells are in the lymph nodes, the disease may have spread to other parts of the body.

Chemotherapy is the use of drugs to kill cancer cells. This type of treatment is called systemic therapy because the drugs enter the bloodstream and travel through the body.Clinical trials are in progress to find the best ways to use chemotherapy to treat stomach cancer. Scientists are exploring the benefits of giving chemotherapy before surgery to shrink the tumor, or as adjuvant therapy after surgery to destroy remaining cancer cells. Combination treatment with chemotherapy and radiation therapy is also under study. Doctors are testing a treatment in which anticancer drugs are put directly into the abdomen (intraperitoneal chemotherapy). Chemotherapy also is being studied as a treatment for cancer that has spread, and as a way to relieve symptoms of the disease.

Radiation therapy (also called radiotherapy) is the use of high-energy rays to damage cancer cells and stop them from growing. Like surgery, it is local therapy; the radiation can affect cancer cells only in the treated area. Radiation therapy is sometimes given after surgery to destroy cancer cells that may remain in the area. Researchers are conducting clinical trials to find out whether it is helpful to give radiation therapy during surgery (intraoperative radiation therapy). Radiation therapy may also be used to relieve pain or blockage.

Biological therapy (also called immunotherapy) is a form of treatment that helps the body's immune system attack and destroy cancer cells; it may also help the body recover from some of the side effects of treatment. In clinical trials, doctors are studying biological therapy in combination with other treatments to try to prevent a recurrence of stomach cancer. In another use of biological therapy, patients who have low blood cell counts during or after chemotherapy may receive colony-stimulating factors to help restore the blood cell levels. Patients may need to stay in the hospital while receiving some types of biological therapy.

National Cancer Institute