新辅助治疗方案显着改善了GEJ（胃食管交界处）癌的预后；然而，有很大比例的患者受益于早期切除或调整的治疗方案，并且真正的缓解率只能通过组织病理学来确定。缺乏术前评估反应的方法。这项回顾性研究的目的是评估治疗前和治疗后能谱 CT 碘密度 (IoD) 在预测诊断为 GEJ 腺癌的患者对新辅助化疗的组织病理学反应方面的潜力。回顾性队列研究，共研究了 62 名 GEJ 癌患者。患者在诊断时和术前接受多相 CT 扫描。碘密度图是根据能谱 CT 数据生成的。对所有肿瘤进行组织病理学分析，并根据Becker等人(Cancer.2003；98：1521-1530)确定肿瘤消退等级(TRG)。两名经验丰富的放射科医生在密度最高的肿瘤区域盲目放置 5 个定义的 ROI，并使用最大值进行进一步分析。碘密度根据主动脉碘摄取量进行标准化。此外，根据标准 RECIST 测量评估肿瘤反应。在评估受试者间可靠性后，评估 IoD 值与治疗反应和组织病理学 TRG 的相关性。标准化 ΔIoD（诊断时的 IoD - 新辅助治疗后的 IoD）和新辅助治疗后的标准化 IoD 与 TRG 显着相关。对于响应者和无响应者的检测，归一化 ΔIoD 的受试者工作特征 (ROC) 曲线产生最高的曲线下面积 0.95，灵敏度和特异性分别为 92.3% 和 92.1%。新辅助治疗后的碘密度曲线下面积为 0.88，敏感性和特异性分别为 86.8% 和 84.6%（截止值 0.266）。诊断时的碘密度和 RECIST 没有提供区分有反应者和无反应者的信息。使用新辅助治疗后 IoD 的截止值，在 11 名患者的测试集中对两位读者进行了可靠的应答者和无应答者分类。组内相关系数显示出出色的受试者间可靠性（组内相关系数，>0.9）。最后，使用标准化 ΔIoD 的截止值作为治疗反应的定义，显示出反应者的生存期显着延长。GEJ 癌症新辅助治疗后 IoD 的变化可能是治疗反应的潜在替代指标。版权所有 © 2024 Wolters Kluwer Health，公司保留所有权利。

Neoadjuvant therapy regimens have significantly improved the prognosis of GEJ (gastroesophageal junction) cancer; however, there are a significant percentage of patients who benefit from earlier resection or adapted therapy regimens, and the true response rate can only be determined histopathologically. Methods that allow preoperative assessment of response are lacking.The purpose of this retrospective study is to assess the potential of pretherapeutic and posttherapeutic spectral CT iodine density (IoD) in predicting histopathological response to neoadjuvant chemotherapy in patients diagnosed with adenocarcinoma of the GEJ.In this retrospective cohort study, a total of 62 patients with GEJ carcinoma were studied. Patients received a multiphasic CT scan at diagnosis and preoperatively. Iodine-density maps were generated based on spectral CT data. All tumors were histopathologically analyzed, and the tumor regression grade (TRG) according to Becker et al ( Cancer . 2003;98:1521-1530) was determined. Two experienced radiologists blindly placed 5 defined ROIs in the tumor region of highest density, and the maximum value was used for further analysis. Iodine density was normalized to the aortic iodine uptake. In addition, tumor response was assessed according to standard RECIST measurement. After assessing interrater reliability, the correlation of IoD values with treatment response and with histopathologic TRG was evaluated.The normalized ΔIoD (IoD at diagnosis - IoD after neoadjuvant treatment) and the normalized IoD after neoadjuvant treatment correlated significantly with the TRG. For the detection of responders and nonresponders, the receiver operating characteristic (ROC) curve for normalized ΔIoD yielded the highest area under the curve of 0.95 and achieved a sensitivity and specificity of 92.3% and 92.1%, respectively. Iodine density after neoadjuvant treatment achieved an area under the curve of 0.88 and a sensitivity and specificity of 86.8% and 84.6%, respectively (cutoff, 0.266). Iodine density at diagnosis and RECIST did not provide information to distinguish responders from nonresponders. Using the cutoff value for IoD after neoadjuvant treatment, a reliable classification of responders and nonresponders was achieved for both readers in a test set of 11 patients. Intraclass correlation coefficient revealed excellent interrater reliability (intraclass correlation coefficient, >0.9). Lastly, using the cutoff value for normalized ΔIoD as a definition for treatment response, a significantly longer survival of responders was shown.Changes in IoD after neoadjuvant treatment of GEJ cancer may be a potential surrogate for therapy response.Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.