Gastrointestinal stromal tumors (GISTs) are rare forms of tumors of the gastrointestinal tract. These tumors start in very early forms of special cells found in the wall of the GI tract, called the “interstitial cells of Cajal” (ICCs). These cells are a part of autonomic nervous system, which helps in regulating food digestion. ICCs are sometimes called the “pacemakers” of the GI tract because they direct the muscles in the digestive system to contract to move food and liquid through the GI tract.
Most of the GISTs develop in the stomach. Others start in the small intestine, but GISTs can start anywhere along the GI tract. Very few cases of GISTs have been reported to starting outside the GI tract in nearby areas. Mostly, GISTs are benign and don’t grow into other areas or spread to other parts of the body. But they can become cancerous if not detected early.
Symptoms associated with gastrointestinal stromal tumors
Most gastrointestinal stromal tumors (GISTs) develop in the small intestine or stomach. These tumors don’t cause any signs or symptoms unless they grow larger. GISTs are often accompanied by bleeding into the gastrointestinal (GI) tract
. Symptom of this bleeding depends on how fast it occurs. Brisk bleeding into the stomach or small intestines can make bowel movements black and cause a person to vomit blood. Bleeding from the esophagus also causes the same symptoms. Bleeding of the large intestine is likely to turn the stool red with visible blood. Other symptoms of gastrointestinal stromal tumors include:
Sometimes the tumor grows large enough to block the passage of food through the stomach or intestine which leads to severe abdominal pain
Diagnosis of gastrointestinal stromal tumors
- Your doctor will go through your medical history and examine symptoms like eating problems, pain, bleeding, etc. You will possibly go through a physical examination to help him get more information about the possible signs of a GIST, like a mass in the abdomen, or other health problems.
- Imaging tests use x-rays, magnetic fields, or radioactive substances to create pictures of the inside of the body. These tests are vital in knowing the suspicious area that might be cancer, spread of cancer, the effectiveness of treatment and signs of cancer recurrence.
- Your doctor will use an endoscope attached with a video camera on the end into the body. The camera sends pictures to a video screen, so that the doctor can clearly see any tumor in the lining of the digestive tract.
- A colonoscopy is performed where a type of endoscope known as a colonoscope is inserted through the anus and up into the colon. This enables the doctor to look at the lining of the entire rectum and colon and to take biopsy samples from any irregular areas.
Treatment for gastrointestinal stromal tumors
There are various treatment options available for gastrointestinal stromal tumors including:
- Surgery: Removal of the tumor is the main treatment for GISTs. Using laparoscopic surgery, a surgeon will remove small tumors through small incisions. As for large tumors, the surgeon may remove parts of the affected organs.
- Targeted therapy: Targeted therapy treats your tumor by working against genetic changes that cause GISTs. Gleevec is the most common targeted therapy. It may be used to shrink large tumor so that a surgery can take place.
- Radiofrequency Ablation (RFA): The process involves the doctor inserting a needle guided by ultrasound into the tumor and generating heat to execute cancer cells. This treatment is successful for several tumors or liver tumors that can't be removed.
Gastrointestinal stromal tumors have the tendency to come back. Therefore, it is important to visit your oncologist
every three to six months after treatment.