Gastrointestinal Stromal Tumor (GIST) is a rare type of cancer that originates in the digestive tract’s specialized nerve cells known as the interstitial cells of Cajal (ICCs). These tumors most commonly occur in the stomach and small intestine but can develop anywhere along the gastrointestinal (GI) tract.
GISTs form when genetic mutations cause uncontrolled cell growth in the GI tract. Unlike other gastrointestinal cancers, GISTs arise from mesenchymal (connective tissue) cells rather than glandular or epithelial cells.
Rare cancer of the digestive tract
Most common in the stomach (60%) and small intestine (30%)
Linked to genetic mutations in KIT or PDGFRA genes
Can be benign or malignant
Early detection improves treatment outcomes
The exact cause of GIST is not well understood, but genetic mutations play a crucial role.
Genetic Mutations – Most GISTs are associated with mutations in the KIT or PDGFRA genes.
Age – More common in individuals over 50.
Family History – Rare familial GIST syndromes exist.
Neurofibromatosis Type 1 (NF1) – Patients with this genetic disorder have a higher risk.
No Known Lifestyle Factors – Unlike many cancers, GIST is not strongly linked to diet, smoking, or alcohol.
Early-stage GISTs may not cause noticeable symptoms. As tumors grow, symptoms may include:
Abdominal pain or discomfort
Unexplained weight loss
Nausea and vomiting
Blood in stool or black, tarry stools (melena)
Fatigue due to anemia
Feeling full quickly after eating
GISTs are classified based on genetic mutations and tumor behavior.
Results from mutations in the KIT gene, leading to excessive cell growth.
Involves mutations in the platelet-derived growth factor receptor alpha (PDGFRA) gene.
No detectable KIT or PDGFRA mutations; often associated with other rare genetic alterations.
Inherited genetic mutations increase susceptibility to GIST.
Doctors use multiple tests to diagnose and assess GIST:
Endoscopy – Examines the digestive tract with a camera.
Biopsy – Collects a tissue sample for analysis.
CT Scan or MRI – Identifies tumor size and location.
PET Scan – Detects metastasis and treatment response.
Molecular Testing – Confirms KIT or PDGFRA mutations for targeted therapy selection.
Treatment depends on tumor size, location, genetic mutations, and metastasis.
Preferred for localized, non-metastatic GISTs.
Minimally invasive laparoscopic surgery may be an option for small tumors.
Imatinib (Gleevec) – First-line treatment for unresectable or metastatic GIST.
Sunitinib (Sutent) – Used when Imatinib is ineffective.
Regorafenib (Stivarga) – Third-line treatment for resistant GIST.
Rarely used but may help relieve symptoms in advanced cases.
Not typically effective for GIST but may be considered in rare cases.
Prognosis varies based on tumor size, mitotic rate, and genetic profile.
Localized GIST (No spread) – 85-90% five-year survival rate.
Regionally spread GIST – 50-70% survival rate.
Metastatic GIST – 15-30% survival rate.
Tumor size and location – Larger tumors have a higher risk of recurrence.
Mitotic rate – Faster-growing tumors have worse outcomes.
Genetic mutations – Certain mutations respond better to targeted therapy.
While there are no proven ways to prevent GIST, some measures may help in early detection and management.
Genetic Counseling – If you have a family history of GIST.
Regular Health Checkups – Helps detect tumors early.
Managing Neurofibromatosis Type 1 (NF1) – Increased monitoring for individuals with NF1.
Managing GIST involves long-term medical care and lifestyle adjustments.
Regular Follow-ups – Monitoring for recurrence is essential.
Adhering to Targeted Therapy – Consistent medication use improves outcomes.
Nutritional Support – A balanced diet helps maintain strength.
Support Groups – Connecting with others provides emotional support.