• Relapses affect the liver & peritoneum & rarely the bone
  • Risk of relapse is high w/ ruptured tumors

• Evaluate tumor response by checking for tumor shrinkage, tumor density changes on computed tomography (CT) scan, & absence of tumor progression
• For gastrointestinal stromal tumors (GISTs) <2 cm w/o high-risk endoscopic ultrasound (EUS) features, consider endoscopic surveillance every 6-12 months

Post-surgery

Completely Resected Tumors w/ or w/o Pre-operative Imatinib

• Clinical evaluation every 3-6 months x 5 years, then annually
  • May be less frequent for small tumors (<2 cm)

• Abdominal/Pelvic CT every 3-6 months x 3-5 years, then annually

Metastatic Disease or Persistent Gross Residual Disease w/ or w/o Pre-op Imatinib

• Clinical evaluation & abdominal/pelvic CT every 3-6 months
  • May be less frequent for small tumors (<2 cm)

Management of Disease Progression

Limited Disease Progression

• Continue or increase Imatinib dose as tolerated or may change to Sunitinib & reassess tumor response via positron emission tomography (PET) or CT
• For progressing lesions while continuing Imatinib, consider surgical resection if still feasible, radiofrequency ablation or embolization, or palliative radiation therapy for bone metastases

Systemic Disease Progression

• Increase Imatinib dose as tolerated or may change to Sunitinib & assess response via PET or CT
• If still w/ limited or systemic disease progression, consider Regorafenib, a clinical trial or supportive care