A safety evaluation of imatinib mesylate in the treatment of gastrointestinal stromal tumor.

INTRODUCTION: For the last 15 years, imatinib mesylate has been the first line treatment of choice for advanced (metastatic) GIST. AREAS COVERED: This review describes key efficacy data on imatinib for the treatment of GIST, and focuses on safety and tolerability of imatinib, with emphasis on common adverse events management and long term toxicity profile. EXPERT OPINION: Imatinib has been the standard of care for metastatic GIST and probably will continue to be so for the next few years. Still, despite dramatic responses initially, imatinib drug resistance continues to be the major factor for treatment discontinuation. The toxicity profile of imatinib has been well characterized, and although the majority of patients experience an adverse event during treatment with imatinib, these side effects are usually mild and manageable, with the majority of patients continuing treatment uninterruptedly. Early concerns regarding imatinib related cardiotoxicity in GIST have not been confirmed in large prospective randomized trials, with reports indicating a low incidence of approximately 0.2%-0.4%. Future strategies for treatment of imatinib resistant GIST will probably include novel tyrosine kinase inhibitors, combination therapies or immunotherapy.