Locally Advanced Rectal Cancer: Added Value of Diffusion-weighted MR Imaging in the Evaluation of Tumor Response to Neoadjuvant Chemo- and Radiation Therapy
Locally Advanced Rectal Cancer: Added Value of Diffusion-weighted MR Imaging in the Evaluation of Tumor Response to Neoadjuvant Chemo- and Radiation Therapy
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DOI：
10.1148/radiol.2532090027
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发表时间：
2009-10-01
期刊：
影响因子：
19.7
通讯作者：
Choi, Byung Ihn
中科院分区：
文献类型：
--
作者：
Kim, Seung Ho;Lee, Jeong Min;Choi, Byung Ihn
目的：探讨扩散加权（DW）磁共振（MR）成像在评价局部进展期直肠癌患者新辅助联合化疗和放疗（CRT）的完全缓解（CR）中的附加价值。材料和方法：本回顾性研究获得了机构审查委员会的批准，并免除了患者知情同意书的要求。本研究纳入了连续40例接受CRT和后续手术的局部晚期直肠癌（>= T3或淋巴结阳性）患者。所有患者均接受了CRT前后1.5 T直肠MR成像和CRT后DW MR成像。对于定性分析，两名对病理分期和既往影像学数据不知情的放射科医生回顾性和独立地审查了2周间隔内的常规MR图像以及MR图像和DW MR图像的组合集，并记录了他们对新辅助CRT的CR的置信水平。用受试者工作特征曲线（ROC）分析计算每位审查者的诊断准确性。对于定量分析，第三位放射科医师测量感兴趣区域的表观扩散系数（ADC）三次。比较CR组与非CR组的平均ADC。以病理报告为参考标准。结果：诊断准确率在对两名审查员的DW MR图像进行额外审查后，CR评价中的ROC曲线下面积[Az]显著改善：对于评审员1，Az从0.676提高到0.876（P = .005），而对于评审员2，Az从0.658提高到0.815（P = .036）。平均ADC（[1.62 +/- 0.36] x 10（-3）mm（2）/sec）CR组（n = 11）的标准差显著高于CR组（n = 11），非CR组（n = 29）的（[1.04 +/- 0.24] x 10（-3）mm（2）/sec）结论：在评价局部进展期直肠癌患者新辅助CRT的CR时，在常规MR成像基础上增加DW MR成像的诊断准确性优于单独使用常规MR成像。(C)RSNA，2009年
Purpose: To investigate the added value of diffusion-weighted (DW) magnetic resonance (MR) imaging in the evaluation of complete response (CR) to neoadjuvant combined chemotherapy and radiation therapy (CRT) in patients with locally advanced rectal cancer.Materials and Methods: Institutional review board approval was obtained for this retrospective study, and the patient informed consent requirement was waived. Forty consecutive patients with locally advanced rectal cancer (>= T3 or lymph node positive) who underwent CRT and subsequent surgery were enrolled in this study. All patients underwent pre- and post-CRT 1.5-T rectal MR imaging and post-CRT DW MR imaging. For qualitative analysis, two radiologists who were blinded to pathologic staging and prior imaging data retrospectively and independently reviewed conventional MR images and the combined set of MR images and DW MR images over a 2-week interval and recorded their confidence level with respect to the CR to neoadjuvant CRT. Diagnostic accuracy was calculated for each reviewer with receiver operating characteristic (ROC) curve analysis. For quantitative analysis, a third radiologist measured the apparent diffusion coefficient (ADC) of the region of interest three times. Mean ADCs in the CR group were compared with those in the non-CR group. Pathology reports served as the reference standard.Results: Diagnostic accuracy (area under the ROC curve [Az]) in the evaluation of CR was significantly improved after additional review of DW MR images for both reviewers: For reviewer 1, Az improved from 0.676 to 0.876 (P = .005), whereas for reviewer 2, Az improved from 0.658 to 0.815 (P = .036). Mean ADC ([1.62 +/- 0.36] x 10(-3) mm(2)/sec) (standard deviation) of the CR group (n = 11) was significantly higher than that ([1.04 +/- 0.24] x 10(-3) mm(2)/sec) of the non-CR group (n = 29) ( P < .0001).Conclusion: Adding DW MR imaging to conventional MR imaging yields better diagnostic accuracy than use of conventional MR imaging alone in the evaluation of CR to neoadjuvant CRT in patients with locally advanced rectal cancer. (C) RSNA, 2009