Information for Taking Gleevec Medication for GIST

Kit+ GIST is a rare cancer of the gastrointestinal (GI) tract. Most GISTs develop in the stomach or in the small intestine, and a small percentage develop elsewhere in the GI tract. GIST is difficult to diagnose and to treat because it "hides" in the abdomen, and often does not cause any physical symptoms.

When GISTs first develop, the tumors stay in one area, such as the stomach. GISTs that stay in their original location are called localized tumors. However, when GISTs advance, they can spread to other parts of the body. When a GIST spreads, it becomes a metastatic tumor. GISTs often grow quite large before they are discovered, and they often spread to other organs, such as the liver.

What Causes It?

An abnormal form of the protein Kit is known to be one of the major causes of
Kit+ GIST. Normal cells have a limited life span. The Kit protein is located on the surface of normal cells. It sends a signal inside the cells that tells them to grow only as needed. When Kit becomes abnormal, its signal stays on constantly and cells become cancerous. Cancerous GIST cells develop a survival "advantage" because they grow faster and live longer than the healthy surrounding cells. The longer the cancerous cells live, the more potential they have to become dangerous, and the more likely they are to spread to other parts of the body.

How It Is Treated

Until the approval of Gleevec^®, patients with Kit+ GIST had very few treatment options. Surgery has been the main treatment of GIST because traditional cancer therapies such as chemotherapy and radiation have been mostly ineffective in treatment of the disease. Some GISTs cannot, however, be surgically removed because they are too large or because they have already spread to another part of the body. Often, even with surgery, parts of the original GIST remain or the GIST returns to another site in the body.

For more information, please click here to see the Gleevec Prescribing Information or contact your physician.