Disparities in tyrosine kinase inhibitor use in older patients with gastrointestinal stromal tumors.

Gastrointestinal stromal tumor (GIST) is the most common soft tissue sarcoma [ [1] Mastrangelo G. Coindre J.M. Ducimetiere F. et al. Incidence of soft tissue sarcoma and beyond: a population-based prospective study in 3 European regions. Cancer. 2012; 118: 5339-5348 Crossref PubMed Scopus (192) Google Scholar ]. The median age of GIST diagnosis is in the seventh decade, with a trend towards increasing incidence with increasing age [ [2] Søreide K. Sandvik O.M. Søreide J.A. Giljaca V. Jureckova A. Bulusu V.R. Global epidemiology of gastrointestinal stromal tumours (GIST): a systematic review of population-based cohort studies. Cancer Epidemiol. 2016; 40: 39-46 Crossref PubMed Scopus (410) Google Scholar ]. Tyrosine kinase inhibitor (TKI) use in both the localized and advanced setting has significantly prolonged overall survival [ [3] Joensuu H. Eriksson M. Sundby Hall K. et al. Survival outcomes associated with 3 years vs 1 year of adjuvant Imatinib for patients with high-risk gastrointestinal stromal tumors: an analysis of a randomized clinical trial after 10-year follow-up. JAMA Oncol. 2020; 6: 1241-1246 Crossref PubMed Scopus (81) Google Scholar , [4] Casali P.G. Zalcberg J. Le Cesne A. et al. Ten-year progression-free and overall survival in patients with unresectable or metastatic GI stromal tumors: long-term analysis of the European Organisation for Research and Treatment of Cancer, Italian sarcoma group, and Australasian gastrointestinal trials group intergroup phase III randomized trial on imatinib at two dose levels. J Clin Oncol. 2017; 35: 1713-1720 PubMed Google Scholar ]. In patients with high-risk disease, following resection of their GIST, adjuvant treatment with at least three years of imatinib is the standard of care [ [3] Joensuu H. Eriksson M. Sundby Hall K. et al. Survival outcomes associated with 3 years vs 1 year of adjuvant Imatinib for patients with high-risk gastrointestinal stromal tumors: an analysis of a randomized clinical trial after 10-year follow-up. JAMA Oncol. 2020; 6: 1241-1246 Crossref PubMed Scopus (81) Google Scholar ]. Patients with metastatic disease receive TKI therapy until disease progression or patient stops tolerating therapy well. Imatinib was the first TKI approved in the metastatic setting; sunitinib and regorafenib are second- and third-line options, respectively. This study explores real world TKI practice patterns in the United States (US) for treatment of GIST in individuals with private insurance coverage, evaluating potential differences in TKI use between younger and older patients (aged 65 and above).