Gastrointestinal Stromal Tumor Signs and Symptoms

Definition

  • Most common mesenchymal tumor originating from the gastrointestinal tract (GIT)
    • Results primarily from KIT or platelet-derived growth factor receptor alpha (PDGFRA) activating mutations
      • Approximately 80% of gastrointestinal stromal tumors (GISTs) have a mutation in the gene encoding the KIT receptor tyrosine kinase
      • Approximately 5-10% of GISTs have a mutation in the gene encoding the PDGFRA receptor tyrosine kinase
      • KIT exon 11 mutations are most common in GIST of all sites while KIT exon 9 mutations are specific for intestinal GIST
      • PDGFRA exon 18 mutations are common in gastric GIST
    • Approximately 10-15% of GISTs have no detectable KIT or PDGFRA mutations
  • Usually occurs in the stomach (60%) or the small intestines (30%)
  • Most common sites of metastases are the liver and/or peritoneal surfaces

Epidemiology

  • Higher incidence in males
  • Frequently occurring in older adults with median age of diagnosis between 65 and 69 years

Signs and Symptoms

  • Abdominal mass
    • May be an incidental finding on endoscopy
  • Abdominal pain or discomfort
  • Early satiety
  • Gastrointestinal (GI) bleeding
  • Hemoperitoneum
  • Anemia
  • GI perforation