Dimitrakopoulou-Strauss Antonia, Ronellenfitsch Ulrich, Cheng Caixia, Pan Leyun, Sachpekidis Christos, Hohenberger Peter, Henzler Thomas
Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
Division of Surgical Oncology and Thoracic Surgery, Department of Surgery, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
Clin Transl Imaging. 2017;5(3):183-197. doi: 10.1007/s40336-017-0229-8. Epub 2017 May 3.
Improvement of the therapeutic approaches in gastrointestinal stromal tumors (GIST) by the introduction of targeted therapies requires appropriate diagnostic tools, which allow sufficient assessment of therapeutic response, including differentiation of true progression from pseudoprogression due to myxoid degeneration or intratumoral hemorrhage. In this literature review the impact and limitations of different imaging modalities used in GIST therapy monitoring are discussed.
PubMed and Cochrane library search were performed using appropriate keywords. Overall, 39 original papers fulfilled the defined criteria and were included in this systematic review.
Morphological imaging modalities like computed tomography (CT) are primarily used for both diagnosis and therapy monitoring. However, therapy with tyrosine kinase inhibitors and other targeted therapies in GIST may lead only to a minor tumor volume reduction even in cases of response. Therefore, the use of Response Evaluation Criteria in Solid Tumors (RECIST) has limitations. To overcome those limitations, modified response criteria have been introduced for the CT-based therapy assessment, like the Choi criteria as well as criteria based on dual energy CT studies. Functional imaging techniques, mostly based on FDG PET-CT are in use, in particular for the assessment of early treatment response.
The impact and the limitations of PET-based therapy monitoring, as well as its comparison with CT, MRI and survival data are discussed in this review. CT is still the standard method for the evaluation of therapy response despite its several limitations. FDG PET-CT is helpful for the assessment of early therapy response; however, more prospective data are needed to define its role as well as the appropriate time intervals for therapy monitoring. A multiparametric evaluation based on changes in both morphological and functional data has to be assessed in further prospective studies.
通过引入靶向治疗来改进胃肠道间质瘤（GIST）的治疗方法需要合适的诊断工具，以便充分评估治疗反应，包括区分因黏液样变性或瘤内出血导致的假进展与真正的疾病进展。在这篇文献综述中，讨论了用于GIST治疗监测的不同成像方式的影响和局限性。
使用适当的关键词在PubMed和Cochrane图书馆进行检索。总体而言，39篇原始论文符合既定标准并被纳入本系统评价。
形态学成像方式如计算机断层扫描（CT）主要用于诊断和治疗监测。然而，在GIST中使用酪氨酸激酶抑制剂和其他靶向治疗，即使在有反应的情况下，也可能仅导致肿瘤体积轻微缩小。因此，实体瘤疗效评价标准（RECIST）的应用存在局限性。为克服这些局限性，已引入基于CT的治疗评估的改良反应标准，如Choi标准以及基于双能CT研究的标准。功能成像技术主要基于FDG PET-CT，尤其用于评估早期治疗反应。
本综述讨论了基于PET的治疗监测的影响和局限性，以及其与CT、MRI和生存数据的比较。尽管CT有一些局限性，但它仍然是评估治疗反应的标准方法。FDG PET-CT有助于评估早期治疗反应；然而，需要更多前瞻性数据来确定其作用以及治疗监测的合适时间间隔。在进一步的前瞻性研究中，必须评估基于形态学和功能数据变化的多参数评估。
