[A Case of the Large Rectal GIST Treated by Laparoscopic Anus Preserving Operation after Neoadjuvant Therapy with Imatinib Mesylate].

A 50s old woman admitted to our hospital with anal pain, who was diagnosed as rectal gastrointestinal stromal tumor (GIST). After neoadjuvant therapy with imatinib mesylate for 6 months, the tumor reduced by 75% from its original size and anus preserving operation(low anterior resection)was performed. After operation adjuvant therapy with imatinib mesylate was performed for 2 years and 6 months. The patient is alive without recurrence 5 years after surgery. It is suggested that neoadjuvant therapy with imatinib mesylate is useful and safety for large rectal GIST, from the standpoint of anal preservation.