Adjuvant imatinib treatment in gastrointestinal stromal tumor

Abstract

Imatinib mesylate is approved for the adjuvant treatment of KIT-positive gastrointestinal stromal tumor (GIST) following surgical resection. However, uncertainty remains in terms of patient eligibility for adjuvant treatment and the optimal duration of treatment. Here, we present two challenging patient cases encountered in clinical practice that highlight the ambiguity in the current recommendations for adjuvant imatinib in GIST and discuss our approaches and rationales for treatment. The first case involves a 36-year-old man with a 7 cm duodenal GIST and possible tumor rupture during surgical resection. This patient's risk of GIST recurrence was either intermediate or high depending on which risk stratification criteria were used. The patient was treated with adjuvant imatinib for 3 years and experienced disease recurrence 14 months after the completion of treatment. Imatinib treatment was reintroduced, and the patient is in partial response 17 months later. The second case involves a 46-year-old woman at high risk of recurrence following surgical resection. Adjuvant treatment with imatinib was initiated. After considering the patient's initial high risk and good side-effect profile, the decision was made to continue adjuvant imatinib treatment for 5 years. As of May 2013, the patient has been receiving continuous imatinib treatment for 52 months, with no sign of progression. These reports exemplify the challenges faced in clinical practice because of uncertainties in optimal risk stratification criteria and duration of treatment. They stress the importance of individualized treatment and shared decision making between the physician and the patient.