Efficacy and Economic Value of Adjuvant Imatinib for Gastrointestinal Stromal Tumors

Objective. This article presents the clinical effectiveness and cost‐effectiveness of the use of adjuvant imatinib mesylate for treating patients with localized primary gastrointestinal stromal tumors (GISTs) and discusses the impact of prolonged treatment with adjuvant imatinib on health care costs. Methods. A systematic review of the medical literature was conducted to explore recently reported clinical trials demonstrating the clinical benefit of adjuvant imatinib in GISTs, along with analyses discussing the economic impact of adjuvant imatinib. Results. Two phase III trials have demonstrated a significant clinical benefit of adjuvant imatinib treatment in GIST patients at risk of recurrence after tumor resection. Guidelines now suggest adjuvant treatment for at least 3 years in patients at high risk of recurrence. Despite this clinical effectiveness, prolonged use of adjuvant imatinib can lead to an increase in the risk for adverse events and to increased costs for both patients and health care systems. However, the increased cost is partially offset by cost reductions associated with delayed or avoided GIST recurrences. Three years of adjuvant treatment in high‐risk patients was concluded to be cost‐effective. Therefore, the careful selection of patients who are most likely to benefit from treatment can lead to improved clinical outcomes and significant cost savings. Conclusion. Although introducing adjuvant imatinib has an economic impact on health plans, this effect seems to be limited. Several analyses have demonstrated that adjuvant imatinib is more cost‐effective for treating localized primary GISTs than surgery alone. In addition, 3 years of adjuvant imatinib is more cost‐effective than 1 year of adjuvant therapy.