KIT and neoplasm: In the univariate and multivariate analyses of both PFS with 400 mg/d imatinib and OS, independent favorable factors were age <60 years, smaller tumor size at the initiation of imatinib, the presence of KIT exon 11 mutation, disease control with 400 mg/d imatinib, surgical resection in RD with TKIs, and treatment in period 2.