Gastrointestinal Stromal Tumor (Gist)

Gastrointestinal Stromal Tumors (GISTs)

A gastrointestinal stromal tumor (GIST) is a type of cancer that starts in the digestive system, most commonly in the stomach or small intestine. Imagine it as a growth of abnormal cells, often originating from specialized nerve cells within the walls of your digestive organs. These nerve cells help move food through your body.

Sometimes, GISTs are small and don't cause any noticeable symptoms, growing slowly and without problems for a while. However, as a GIST grows, it can lead to various signs and symptoms:

• Abdominal pain: A common complaint.
• A noticeable lump or swelling in your abdomen: You might feel a growth.
• Fatigue: Feeling tired.
• Nausea and vomiting: Feeling sick to your stomach.
• Cramping pain after eating: A discomfort that often follows meals.
• Loss of appetite: Not feeling hungry when you usually would.
• Feeling full quickly: Feeling satisfied even after eating a small amount of food.
• Dark stools: This can indicate bleeding in the digestive tract.

GISTs can affect people of any age, but they're more common in adults and very rare in children. While the exact cause of most GISTs is unknown, some cases are linked to inherited gene mutations passed down from parents to their children.

Diagnosing a GIST:

Your doctor will likely start by asking about your symptoms and medical history. They might also physically examine your abdomen to check for any unusual growths.

If the symptoms suggest a GIST, further tests may be needed to pinpoint the tumor and understand its characteristics:

• Imaging tests: These use techniques like ultrasound, CT scans, MRI scans, and PET scans to visualize the tumor, determine its size, and locate it within the body. Not all tests are necessary for every patient.
• Upper endoscopy: A long, thin tube with a camera (endoscope) is inserted through your mouth and throat to examine the esophagus, stomach, and the beginning of the small intestine, looking for the tumor.
• Endoscopic ultrasound (EUS): A specialized endoscope with an ultrasound probe at its tip is used. The ultrasound creates images of the tumor, providing detailed information about its size and location.
• Fine-needle aspiration biopsy: A thin needle is guided to the tumor using EUS. A small tissue sample is collected for lab analysis. This can sometimes be challenging to obtain a sufficient tissue sample, and in such cases, surgery may be necessary to remove a larger tissue sample.
• Laboratory tests on biopsies: The collected tissue sample is sent to a laboratory where specialists examine the cells under a microscope to confirm if they are cancerous. Further tests can provide more details about the specific characteristics of the cancer cells, helping to plan the best treatment approach.

Treating a GIST:

Treatment for GIST often involves a combination of surgery and targeted therapy. The specific approach depends on factors like the tumor's size, location, and whether it has spread.

• Surgery: The goal of surgery is to remove the entire tumor, particularly if it hasn't spread to other parts of the body. Minimally invasive techniques, using small incisions, are often used to reduce recovery time. In some cases, if the tumor is very large or has grown into nearby structures, targeted drug therapy might be the first step to shrink the tumor before surgery.
• Targeted therapy: These treatments target specific molecules within the cancer cells that contribute to their growth. For GISTs, the targeted drugs commonly focus on an enzyme called tyrosine kinase. The most commonly used drug for GIST is imatinib (Gleevec). Targeted drugs can be used:
  • After surgery to reduce the risk of the cancer returning.
  • Before surgery to shrink the tumor, making it easier to remove.
  • As the initial treatment if the cancer has spread.
  • If the GIST recurs (comes back).

If imatinib isn't effective or stops working, other targeted drugs might be considered. Research in targeted therapy for GIST is ongoing, and new drugs may become available in the future.

Important Note: Not all GISTs require immediate treatment. Small, asymptomatic GISTs may be monitored over time to see if they grow before treatment begins.

Diagnosing soft tissue sarcoma involves a combination of imaging tests and procedures to collect tissue samples for testing.

Imaging tests create pictures of the inside of your body. These pictures can help doctors see the size and location of the sarcoma. Different types of imaging include:

• X-rays: These use beams of energy to create images.
• CT scans (Computed Tomography): These use X-rays and a computer to create detailed cross-sectional images of the body.
• MRI scans (Magnetic Resonance Imaging): These use strong magnets and radio waves to create detailed images of soft tissues.
• PET scans (Positron Emission Tomography): These use a radioactive substance to highlight areas of high activity in the body, which can sometimes help spot cancers.

Taking a Sample (Biopsy): A biopsy is a procedure where a small sample of tissue is removed for examination. For soft tissue sarcoma, the biopsy needs to be planned carefully so it doesn't interfere with any future surgery. It's best to go to a medical center that frequently treats this type of cancer, as their experienced teams are better equipped to choose the right type of biopsy for your specific situation. Different biopsy methods include:

• Core needle biopsy: A thin, hollow needle is used to remove small cylinders (cores) of tissue from the sarcoma. This is often done in several spots within the tumor to get a better representation of the tissue.
• Surgical biopsy: In some cases, a surgeon may remove a larger piece of tissue for testing. This is often done when a core needle biopsy isn't enough to get a clear picture of the cancer.

Lab Testing: The tissue sample is sent to a lab. Doctors called pathologists specialize in examining cells and tissues. They look at the cells under a microscope to determine if they are cancerous. Additional lab tests can provide further details about the type of cancer cells. This information helps determine the best treatment plan.

Treating Soft Tissue Sarcoma: Options and Support

Soft tissue sarcoma is a type of cancer that affects the soft tissues of the body, often found in the arms and legs. Treatment choices depend on things like the size, type, and location of the tumor.

Surgery: A common treatment is surgery to remove the cancer. Often, the surgeon will also remove some of the healthy tissue surrounding the tumor. In the past, this sometimes meant removing the entire limb. Now, doctors frequently use other methods first, if possible, to try to avoid removing a whole limb.

Other Approaches:

• Radiation Therapy: This treatment uses powerful energy beams, like X-rays or protons, to kill cancer cells. Imagine a machine that moves around you, focusing the energy beams on the cancer. Radiation can be used:

  • Before surgery: To shrink the tumor, making it easier to remove.
  • During surgery: To deliver a higher dose directly to the tumor, potentially sparing healthy tissue.
  • After surgery: To kill any remaining cancer cells. A special type of radiation called intraoperative radiation therapy (IORT) delivers a higher dose directly to the tumor during surgery.

• Chemotherapy: This uses strong medicines to kill cancer cells. These medicines are often given through a vein, but some come in pill form. Different types of sarcoma respond differently to chemotherapy. For example, rhabdomyosarcoma is often treated with chemotherapy.

• Targeted Therapy: This type of treatment uses medicines that target specific molecules within the cancer cells. These medicines may block the growth or cause the cancer cells to die. Doctors can test the cancer cells to see if a targeted therapy might be effective. Targeted therapies are helpful for some sarcomas, like gastrointestinal stromal tumors (GISTs).

Coping with a Cancer Diagnosis:

A cancer diagnosis can be overwhelming. It's important to remember that you're not alone. Here are some ways to cope:

• Learn About Your Sarcoma: Talk to your healthcare team about your sarcoma, treatment options, and prognosis. Ask questions and gather information to help you make informed decisions.
• Connect with Loved Ones: Maintaining strong relationships with friends and family is crucial for support. They can provide emotional support and practical help, such as taking care of home responsibilities if you need to be hospitalized.
• Seek Support: Talking to someone about your hopes and fears is important. This could be a friend, family member, therapist, counselor, clergy member, or a cancer support group. These resources can offer emotional support and guidance.

Remember, you are not alone in this journey. Your healthcare team and support systems can help you navigate this challenging time.