Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms. Tyrosine kinase inhibitor (TKI) therapy is currently part of routine clinical practice for unresectable and metastatic... Show moreGastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms. Tyrosine kinase inhibitor (TKI) therapy is currently part of routine clinical practice for unresectable and metastatic disease. It is important to assess the efficacy of TKI treatment at an early stage to optimize therapy strategies and eliminate futile ineffective treatment, side effects and unnecessary costs. This systematic review provides an overview of the imaging features obtained from contrast-enhanced (CE)-CT and 2-deoxy-2-[F-18]fluoro-D-glucose ([F-18]FDG) PET/CT to predict and monitor TKI treatment response in GIST patients. PubMed, Web of Science, the Cochrane Library and Embase were systematically screened. Articles were considered eligible if quantitative outcome measures (area under the curve (AUC), correlations, sensitivity, specificity, accuracy) were used to evaluate the efficacy of imaging features for predicting and monitoring treatment response to various TKI treatments. The methodological quality of all articles was assessed using the Quality Assessment of Diagnostic Accuracy Studies, v2 (QUADAS-2) tool and modified versions of the Radiomics Quality Score (RQS). A total of 90 articles were included, of which 66 articles used baseline [F-18]FDG-PET and CE-CT imaging features for response prediction. Generally, the presence of heterogeneous enhancement on baseline CE-CT imaging was considered predictive for high-risk GISTs, related to underlying neovascularization and necrosis of the tumor. The remaining articles discussed therapy monitoring. Clinically established imaging features, including changes in tumor size and density, were considered unfavorable monitoring criteria, leading to under- and overestimation of response. Furthermore, changes in glucose metabolism, as reflected by [F-18]FDG-PET imaging features, preceded changes in tumor size and were more strongly correlated with tumor response. Although CE-CT and [F-18]FDG-PET can aid in the prediction and monitoring in GIST patients, further research on cost-effectiveness is recommended. Show less
Ripretinib (DCC-2618) is a novel, type II tyrosine switch control inhibitor designed to broadly inhibit activating and drug-resistant mutations in KIT and PDGFRA. Ripretinib has emerged as a... Show moreRipretinib (DCC-2618) is a novel, type II tyrosine switch control inhibitor designed to broadly inhibit activating and drug-resistant mutations in KIT and PDGFRA. Ripretinib has emerged as a promising investigational agent for the treatment of gastrointestinal stromal tumor owing to targeted inhibition of secondary resistance mutations that may develop following treatment with prior line(s) of tyrosine kinase inhibitors. Here we describe the rationale and design of intrigue (NCT03673501), a global, randomized (1:1), open-label, Phase III study comparing the safety and efficacy of ripretinib versus sunitinib in patients with advanced gastrointestinal stromal tumor following imatinib. The primary end point is progressionfree survival and key secondary objectives include objective response rate and overall survival. Show less
Farag, S.; Geus-Oei, L.F. de; Graaf, W.T. van der; Coevorden, F. van; Grunhagen, D.; Reyners, A.K.L.; ... ; Steeghs, N. 2018