Perspective on updated treatment guidelines for patients with gastrointestinal stromal tumors.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract and present predominantly in middle-aged and older individuals. Historically, the outlook for patients with GISTs was very poor because of the general lack of efficacy of conventional chemotherapy and the often limited surgical options. However, the recognition of the role of mutations of the v-kit Hardy/Zuckerman 4 feline sarcoma viral oncogene homolog KIT and the platelet derived growth factor receptor alpha gene PDGFRα in the development of GISTs led to the evaluation of potential antitumor effects of the tyrosine kinase inhibitors imatinib and, more recently, sunitinib. Consequently, these molecularly targeted therapies were introduced into clinical practice, and the outcome for patients with GISTs improved considerably. In the last few years, the European Society of Medical Oncology, the National Comprehensive Cancer Network, and the Canadian Advisory Committee on GIST each published a major set of guidelines or practice recommendations for the management of patients with GIST. In the current review, the latest recommendations from each organization are summarized in terms of diagnosis and risk assessment, tumor staging, surgical and/or drug treatment of primary resectable and recurrent metastatic disease, and patient follow-up and assessment. In addition, areas of consensus and points of divergence among the guidelines are highlighted along with any unresolved issues.