A 60-year-old man undergoes wedge resection of a 5 cm gastric tumour arising from the muscularis propria. Histology shows spindle cell neoplasm positive for CD117 and DOG1, negative for desmin and S100. Mitotic count is 8 per 50 high power fields. What is the most appropriate adjuvant management?
- A No adjuvant therapy, surveillance only
- B Adjuvant sunitinib 50 mg daily
- C Adjuvant imatinib 400 mg daily ✓
- D Adjuvant FOLFOX chemotherapy
Correct answer: C. Adjuvant imatinib 400 mg daily
Explanation
CD117 (KIT) positivity identifies a gastrointestinal stromal tumour. Tumours larger than 5 cm with mitotic rate above 5 per 50 high power fields fall into a higher risk category, and adjuvant imatinib, a tyrosine kinase inhibitor against KIT, is indicated for at least 36 months. Sunitinib is second line for imatinib resistance, and conventional chemotherapy has no activity in GIST.
Reference: Schwartz's Principles of Surgery, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.