Clinicopathological Features Of Ruptured Gist In The Registry Study Of High Risk Gist Patients After Complete Resection In Japan

96 Background: Ruptured GIST, either preoperatively or intraoperatively, has ominous prognosis and is classified as high risk GIST in the modified Fletcher risk stratification. Although patients (pts) with these GISTs are recommended for 3-year imatinib adjuvant therapy, their clinicopathological features and compliance of guidelines are unknown. Methods: Between Dec. 2012 and Aug. 2015, 474 pts with high-risk GISTs locally diagnosed were prospectively registered. Among them, 453 pts with GISTs histologically confirmed by central review were analyzed. There were 243 males and 210 females with median age of 65 yrs. In the central review, Hu0026E, immunohistochemistry, and genotyping were tested. Results: Disease was located in the stomach (n = 279), small intestine (n = 137), large intestine (n = 25), or others (n = 12). Median tumor size was 7.7 cm and median mitosis (local pathology) was 10/50HPF. Tumor rupture was seen in 54 pts (12%) who had preoperative rupture (28 pts) or intraoperative rupture (25 pts)....