[Imaging evaluation of targeted therapy for gastrointestinal stromal tumor]

Imaging study is the primary method to evaluate the efficacy of targeted therapy for gastrointestinal stromal tumor(GIST). The application of RECIST morphological criteria has limitations in the evaluation of targeted therapy, which may result in incorrect reflection of responses by conventional size-based criteria. Recent proposed Choi criteria, which combined the size and the CT value, has extended the application of radiology in the evaluation of GIST. The early change of apparent diffusion coefficient(ADC) values on diffusion-weighted imaging(DWI) can reflect the response of GIST to targeted therapy. The prominent change of ADC can be detected within one week after therapy. Through comprehensive analysis of the imaging characteristics associated with the biological behavior of GIST, new approaches may be developed in the evaluation of response of GIST to targeted therapy.