El Homsi Maria, Yildirim Onur, Gangai Natalie, Shia Jinru, Gollub Marc J, Mazaheri Yousef
Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Quant Imaging Med Surg. 2024 Jun 1;14(6):4110-4122. doi: 10.21037/qims-23-1463. Epub 2024 May 24.
In mucinous rectal cancer, it can be difficult to differentiate between cellular and acellular mucin. The purpose of this study was to evaluate, in patients with mucinous rectal cancer, the value of static enhancement (enh) and pharmacokinetic parameters of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in predicting pathologic complete response.
This retrospective cross-sectional study performed at Memorial Sloan Kettering Cancer Center included 43 patients (24 males and 19 females; mean age, 57 years) with mucinous rectal cancer who underwent MRI at baseline as well as after neoadjuvant chemoradiotherapy but before surgical resection between 2008 and 2019. Two radiologists independently segmented tumors on contrast-enhanced axial 3D T1-weighted images and sagittal DCE magnetic resonance images. On contrast-enhanced axial T1-weighted images, the static parameters enh and relative enhancement (renh) were estimated. On DCE images, the pharmacokinetic parameters K, k, relative K (rK), and relative k (rk) were estimated. Associations between all parameters with pathologic complete response were tested using Wilcoxon signed-rank tests. Receiver operating characteristic (ROC) analysis was performed to assess the area under the curve (AUC) for each parameter.
Of the 43 patients who were included in the study, 42/43 (98%) had evaluable contrast-enhanced axial T1-weighted images and 35/43 (81%) had evaluable DCE images. Of the patients with evaluable contrast-enhanced axial T1-weighted images, 9/42 (21%) had pathologic complete response and 33/42 (79%) did not have pathologic complete response. For reader 1, enh(pre-neoadjuvant chemotherapy), enh(post-neoadjuvant chemotherapy), and renh were significant predictors of pathologic complete response [P=0.045 (AUC =0.73), 0.039 (AUC =0.74), and 0.0042, respectively]. For reader 2, enh(pre-neoadjuvant chemotherapy) and renh were significant predictors [P=0.021 (AUC =0.77) and 0.002, respectively]. For renh, the AUC was 0.83 for reader 1, and 0.82 for reader 2. Meanwhile, of those patients with evaluable DCE images, 9/35 (26%) had pathologic complete response and 26/35 (74%) did not have pathologic complete response. K(pre-neoadjuvant chemotherapy), k(pre-neoadjuvant chemotherapy), and rk were significant predictors [P=0.016 (AUC =0.73), 0.00057 (AUC =0.81), and 0.0096 (AUC =0.74), respectively].
Static and pharmacokinetic parameters of contrast-enhanced MRI show promise to predict neoadjuvant treatment response. Static enh parameters, which are simpler to assess, showed the strongest prediction.
在黏液性直肠癌中，区分细胞性黏液和无细胞性黏液可能具有挑战性。本研究的目的是评估黏液性直肠癌患者中，静态增强（enh）和动态对比增强（DCE）磁共振成像（MRI）的药代动力学参数在预测病理完全缓解方面的价值。
这项在纪念斯隆凯特琳癌症中心进行的回顾性横断面研究纳入了43例黏液性直肠癌患者（24例男性和19例女性；平均年龄57岁），这些患者在2008年至2019年间于基线时以及新辅助放化疗后但手术切除前接受了MRI检查。两名放射科医生在对比增强轴向3D T1加权图像和矢状面DCE磁共振图像上独立分割肿瘤。在对比增强轴向T1加权图像上，估计静态参数enh和相对增强（renh）。在DCE图像上，估计药代动力学参数K、k、相对K（rK）和相对k（rk）。使用Wilcoxon符号秩检验来检验所有参数与病理完全缓解之间的关联。进行受试者操作特征（ROC）分析以评估每个参数的曲线下面积（AUC）。
在纳入研究的43例患者中，42/43（98%）有可评估的对比增强轴向T1加权图像，35/43（81%）有可评估的DCE图像。在有可评估对比增强轴向T1加权图像的患者中，9/42（21%）有病理完全缓解，33/42（79%）没有病理完全缓解。对于读者1，enh（新辅助化疗前）、enh（新辅助化疗后）和renh是病理完全缓解的显著预测因素[P分别为0.045（AUC =0.73）、0.039（AUC =0.74）和0.0042]。对于读者2，enh（新辅助化疗前）和renh是显著预测因素[P分别为0.021（AUC =0.77）和0.002]。对于renh，读者1的AUC为0.83，读者2的AUC为0.82。同时，在有可评估DCE图像的患者中，9/35（26%）有病理完全缓解，26/35（74%）没有病理完全缓解。K（新辅助化疗前）、k（新辅助化疗前）和rk是显著预测因素[P分别为0.016（AUC =0.73）、0.00057（AUC =0.81）和0.0096（AUC =0.74）]。
对比增强MRI的静态和药代动力学参数有望预测新辅助治疗反应。更易于评估的静态enh参数显示出最强的预测能力。
