关键词: 胃肠间质瘤, 伊马替尼, 计算机断层扫描, 预后

Abstract:

Clinical significance of changes in CT signs after imatinib treatment for unresectable or metastatic gastrointestinal stromal tumors        LIN Zhen-meng,WEI Sheng-hong,YE Zai-sheng, et al. Department of Gastrointestinal Tumor Surgery,Fujian Medical University Cancer Hospital, Fuzhou 350014,China
Corresponding author:CHEN Lu-chuan,E-mail:317871454@qq.com
Abstract    Objective    To study CT image changes  after  imatinib mesylate treatment in patients with metastatic/unresectable gastrointestinal stromal tumor(GIST). Methods    Forty-three patients suffering metastatic/unresectable GIST were treated with imatinib in Fujian Medical University Cancer Hospital between September 2008 and November 2016. All patients were assessed by contrast-enhanced CT after oral imatinib treatment for three months. Progression free survival(PFS) and overall survival（OS）were recorded. The tumor size and density ［Hounsfield unit(HU)］ on CT were measured on axial images. Clinical effects were evaluated according to Choi. The patients were separated into two groups: good responder group［complete response(CR)+partial response（PR）］ and poor responder group［stable disease (SD)+progression of disease(PD). The clinicopathologic features (age，gender，location of tumor,tumor size,calcifications, seroperitoneum, cystic necrosis,gene mutation）were compared between two groups  after 3 months treatment. The differences of PFS and OS between PR evaluated by the length change and HU change were employed by Kaplan-Meier test. The accuracies of predicting two-year progress between length change rates and HU change rates were appraised by the receiver operating characteristic curve（ROC）. Results In the 43 patients, no patient got CR, 27（62.8%）got PR, 13（30.2%）got SD, and 3 (7.0%) got PD. The value in good responder group was significantly correlated with the gene mutation, and had nothing to do with the age, gender, location of tumor, tumor size, calcifications, seroperitoneum and cystic necrosis. All the patients were followed up successfully, and median of follow-up time , PFS and OS were 65.5(15-96), 15.8 and  43.3 months, respectively. There was not statistical significance of PFS and OS between PR according to the length change rates and PR according to HU change rates（P=0.996,0.771）. The accuracies of predicting two-year progress by length change rate and HU change rates with area under ROC curve were 0.853 and 0.868 respectively. Conclusion    The targeted therapy of metastatic/unresectable GIST is related to the type of gene mutation. The length change rates and HU change rates which possess moderate prediction accuracy, can be used in evaluation of GIST treated by imatinib.

Key words: gastrointestinal stromal tumor, imatinib, computed tomography, prognosis