[Two Cases of Large Gastrointestinal Stromal Tumors Safely and Completely Resected by Laparoscopic Surgery Followed by Neoadjuvant Imatinib Therapy].

ABSTRACT

Case 1, the patient was a 51-year-old man. Upper gastrointestinal endoscopy revealed a submucosal tumor with delle at the posterior wall of the gastric body, and the biopsy demonstrated a diagnosis of GIST. Abdominal CT scan showed a tumor at the size of 130×110×90 mm. Six months after administration of 400 mg/day of imatinib, the maximum diameter was reduced to 55 mm, then partial gastrectomy was performed by laparoscopic surgery. He continued to take imatinib after the surgery for 3 years, and he is alive without recurrence 4 years postoperatively. Case 2, the patient was a 68-year-old man. An abdominal CT scan showed a tumor at the size of 160×120×85 mm on the posterior outside of the stomach, but no submucosal tumor could be identified by upper gastrointestinal endoscopy. Gastric GIST was suspected and he started taking imatinib 400 mg/day. Because the Grade 3 generalized eruption was appeared, imatinib was discontinued, and then the dose was reduced. Nine months after the initiation of the treatment, the maximum diameter was reduced to 90 mm, and laparoscopic partial gastrectomy was performed. The patient is followed up without administration of imatinib after the surgery, and is alive without recurrence for 1 year and 6 months postoperatively. We report 2 cases that the large gastric GIST was able to be resected safely and completely due to tumor shrinkage by neoadjuvant imatinib therapy.