Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Gastrointestinal Stromal Tumors

By

Minhhuyen Nguyen

, MD, Fox Chase Cancer Center, Temple University

Last full review/revision Mar 2021| Content last modified Mar 2021
Click here for the Professional Version

Gastrointestinal stromal tumors are rare cancers that start in specific cells in the wall of the digestive tract.

Gastrointestinal stromal tumors (GISTs) are cancerous (malignant) tumors that develop from a specific kind of cell (mesenchymal precursor cells) within the wall of the esophagus Throat and Esophagus The throat (pharynx—see also Throat) lies behind and below the mouth. When food and fluids leave the mouth, they pass through the throat. Swallowing of food and fluids begins voluntarily and... read more , stomach Stomach The stomach is a large, bean-shaped, hollow muscular organ consisting of three regions: Cardia Body (fundus) Antrum (See also Overview of the Digestive System.) read more , or intestines. Most gastrointestinal stromal tumors are caused by a mutation in a gene called C-KIT that controls the growth of cells. Most (60 to 70%) of these tumors occur in the stomach, 20 to 25% occur in the small intestine Small Intestine The duodenum is the first segment of the small intestine, and the stomach releases food into it. Food enters the duodenum through the pyloric sphincter in amounts that the small intestine can... read more , and a small percentage occurs in the esophagus, colon Large Intestine The large intestine consists of the Cecum and ascending (right) colon Transverse colon Descending (left) colon Sigmoid colon (which is connected to the rectum) read more , and rectum Rectum and Anus The rectum is a chamber that begins at the end of the large intestine, immediately following the sigmoid colon, and ends at the anus (see also Overview of the Anus and Rectum). Ordinarily, the... read more .

The average age at diagnosis is 50 to 60. People who have had radiation therapy to the abdomen for the treatment of other tumors can develop gastrointestinal stromal tumors at a later time. These tumors usually grow slowly, but some can grow more rapidly and spread to other sites (metastasize).

Symptoms

Symptoms of gastrointestinal stromal tumors depend on the location of the tumor but include abdominal pain, bleeding, indigestion, and a feeling of fullness after eating a small meal. Nausea and vomiting can occur if the tumor has grown large enough to block the digestive tract.

Diagnosis

  • Endoscopy or colonoscopy

  • Imaging tests

A doctor may use an endoscope or colonoscope (a flexible viewing tube—see Endoscopy Endoscopy Endoscopy is an examination of internal structures using a flexible viewing tube (endoscope). Endoscopy can also be used to treat many disorders because doctors are able to pass instruments... read more ) to locate the tumor and do a biopsy (remove a tissue sample for examination under a microscope). A wireless battery-powered capsule that contains one or two small cameras (see Video Capsule Endoscopy Video Capsule Endoscopy Video capsule endoscopy (wireless video endoscopy) is a procedure in which the person swallows a battery-powered capsule. The capsule contains one or two small cameras, a light, and a transmitter... read more ) can also be used to show tumors of the small intestine, but this technique does not allow the doctor to do a biopsy.

Treatment

  • Surgical removal

If the cancer has not spread to other organs, doctors remove it surgically.

If the cancer has spread, doctors often treat it with a certain type of chemotherapy drug (imatinib). If imatinib does not help, doctors may give other chemotherapy drugs such as sunitinib and regorafenib.

Another drug called avapritinib can be given to people who have gastrointestinal stromal tumors that cannot be treated with surgery or that have spread to other parts of the body and that are caused by a genetic mutation called PDGFRA exon 18.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Regorafenib
Avapritinib
SUTENT
GLEEVEC
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version

Test your knowledge

Peptic Ulcer Disease
A peptic ulcer is a sore that forms where the lining of the stomach or duodenum (the first part of the small intestine) has been eaten away by stomach acids or digestive juices. In addition to Helicobacter pylori infection of the stomach, what is the most common cause of peptic ulcer?
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
TOP