Abstract:

Early evaluation of imatinib in treatment of gastrointestinal stromal tumor using CT imaging ZHANG Xiao-peng *, TANG Lei, SHEN Lin , et al. *Department of Radiology， Peking University School of Oncology & Beijing Cancer Hospital, Beijing 100036, China Corresponding author：ZHANG Xiao-peng，E-mail：zxp@bjcancer.org Abstract Objective To compare the value of RECIST and Choi criteria in the evaluation of imatinib in treatment of GIST. Methods The clinical data of 176 cases of GIST treated by imatinib during April 2003 to January 2008 were analyzed retrospectively. Among them，26 cases had medium and short term (2-6months) CT follow-ups were enrolled into the study. CT scans were performed on Siemens plus4 and GE 64-slices MDCT. The size and CT values were measured on axial images. The mean length-diameter and CT values were measured according to RECIST and Choi criteria(≤5/organ, ≤10/case). The change rate of length-diameter and CT values were computed. All patients were divided into good-response group (GoodR) and poor-response group (PoorR) according to RECIST and Choi criteria respectively. The TTP of different groups divided by different criteria using Kaplan-Meier were compared. Results There were 7 cases of good responders and 19 cases of poor responders by RECIST criteria, and the response rate was 27%. There were 19 cases of responders and 7 cases of non-responders by Choi criteria, and the response rate was 73%. The median follow-up was 23.5 months. The median time to progression (TTP) was 17.5 months up to January 2008. There was no statistical significance of TTP between good responder and poor responder groups (P=0.910) according to RECIST criteria, and there was statistical significance of TTP (P=0.000) according to Choi criteria. Conclusion Choi criteria is superior to RECIST criteria in the CT evaluation of GIST treated by imatinib.

Key words: gastrointestinal stromal tumor, imatinib, time to tumor progression, computed tomography

摘要：

目的 比较实体瘤疗效评价标准（RECIST )及Choi标准对伊马替尼治疗胃肠间质瘤（gastroIntestinal stromal tumor，GIST）CT早期疗效评价的应用价值。方法 回顾性分析2003年4月至2008年1月北京大学临床肿瘤学院应用伊马替尼治疗175例复发转移性GIST的临床资料，其中26例行中短期（2~6个月）连续CT复查者纳入研究。采用Siemens plus4单排螺旋CT及GE 64排MDCT。轴位图像测量肿瘤最长径线及最大层面强化CT值，按照RECIST及Choi标准要求累加并平均得到病例长径及CT均值。计算治疗前后长径及CT值变化率，按照RECIST及Choi标准划分为缓解和无缓解两组。用Kaplan-Meier法判断不同标准分组肿瘤进展时间的差异，比较两个标准的应用价值。结果 根据RECIST标准评价治疗缓解 7例，无缓解 19例，缓解率27%；根据Choi标准评价治疗缓解19例，无缓解 7例，缓解率73%。病人中位随访时间23.5个月，截至2008年1月26例病人的中位肿瘤进展时间为17.5个月。根据RECIST标准评效，缓解组和无缓解组肿瘤进展时间差异无统计学意义（P=0.910）；根据Choi标准评效，缓解组和无缓解组肿瘤进展时间差异有统计学意义（P<0.001）。结论 Choi标准用于评价伊马替尼治疗GIST的早期疗效优于RECIST标准。

关键词: 胃肠间质瘤, 伊马替尼 , 肿瘤进展时间 , CT