Zhang X, et al. - The efficacy of sunitinib and imatinib dose escalation as second-line therapy was compared in patients with GIST previously treated with 400mg/d IM in this multi-center cohort study. Researchers analyzed data of 203 patients with recurrent/metastatic GISTs who were treated by SU from 2008.1 to 2016.12, in three tertiary teaching hospitals in southern China from prospectively registered databases, respectively. They defined time to SU failure (TTSF) as from the time of disease progression of 400mg/d IM to failure of SU treatment in both groups. SU was given in 37.5mg continuous daily dose or 50mg 4 weeks on/2 weeks off. After failure on 400mg/d IM, 100 (49.3%) patients received a dose escalation to 600mg/800mg per day (IM group), and 103 directly changed to SU(SU group). Outcomes suggest better progression-free survival in patients who were directly changed to SU than IM dose escalation when standardized dose IM failed. However, the outcome, both time to SU failure or overall survival, is similar to those continued with SU therapy after failure of dose escalation.