Long-term Results of Adjuvant Imatinib Treatment for Localized Gastrointestinal Stromal Tumors after Surgery

Objective: Despite the development of two significant classifications for recurrence risk evaluation among patients engaged with gastrointestinal stromal tumor and corresponding treatment criteria, recurrence happens in a number of the patients who were once classified as ineligible for treatment and hence removed from treatment program. As such, the aim of the present study is to increase the number of patients recognized as eligible for treatment, so as to further reduce recurrence rate of this disease. Materials and Methods: A total of 26 patients from Ilam, Kermanshah, Lorestan, Kurdistan, and some parts of Hamedan, entered this study from 2006 until 2016. The western provinces included have similar socioeconomical conditions. Inclusion criteria were operable tumors confirmed radiologically with a gross size larger than 3 centimeters regardless of the mitosis rate in microscopic power fields, tumor location, or presence of peritoneal involvement during the surgery. Imatinib capsules were administered daily at 400 mg for 3 years. The patients were followed up every 3 months by radiology, ultrasonography, biochemical assessment, and clinical examination. Results and Conclusions: The overall survival after 10-years follow up was 100%, while 5-year survival without relapse was 95%. Mean overall survival was 106 months, and only one patient who had limited peritoneal involvement experienced relapse and he is still alive after 2 years. The drug was well tolerated and no significant side effects were observed.