Managing GIST in the imatinib era: optimization of adjuvant therapy

We reviewed studies evaluating the clinical benefits of 1 year or more of adjuvant imatinib therapy in patients with gastrointestinal stromal tumor (GIST). Data from the Scandinavian Sarcoma Group (SSG) XVIII/AIO Phase III trial of 1 year versus 3 years of adjuvant imatinib support the use of 3 years as standard of care in patients who are at high risk for GIST recurrence following resection. Although adjuvant imatinib therapy prolonged recurrence-free survival in the evaluated trials, overall survival was not significantly increased except in the SSG XVIII/AIO trial. The optimal duration of therapy, and whether high-risk patients should use adjuvant imatinib continuously, remains unknown. The importance of risk assessment, risk stratification and GIST genotype in patient selection is also discussed.