KIT and gastrointestinal stromal tumor: A subsequent ACOSOG phase III, double-blind, randomized trial (Z9001) in patients with KIT-expressing GIST of at least 30 mm in size confirmed that 1 year of adjuvant imatinib (400 mg/day) significantly improved 1-year RFS rates after complete resection compared with placebo (98% versus 83%, P<0.0001)[40].