探讨扩散加权成像（DWI）联合动态对比增强磁共振成像（DCE-MRI）定量参数对局部进展期直肠癌（LARC）患者新辅助治疗后病理完全缓解（pCR）的预测价值。

回顾性分析2022年1月至2025年1月西电集团医院收治的120例LARC患者临床资料，采用肿瘤退缩分级（TRG），将TRG 0级定义为pCR组（n=38），其余为非pCR组（n=82）。比较两组新辅助治疗前后表观扩散系数（ADC）、转运常数（Ktrans）、血管外细胞外间隙体积百分数（Ve）、速率常数（Kep）定量参数。采用Spearman相关分析法分析DWI与DCE-MRI定量参数与LARC新辅助治疗后pCR的相关性，采用ROC曲线分析治疗前DWI联合DCE-MRI定量参数对LARC新辅助治疗后pCR的预测价值。

pCR组治疗后患者ADC高于非pCR组，而Kep、Ve、Ktran均低于非pCR组（P<0.05）；Spearman相关分析结果显示，治疗前ADC与LARC新辅助治疗后pCR呈正相关，Kep、Ve、Ktrans与LARC新辅助治疗后pCR均呈负相关（P<0.05）；ROC曲线分析表明，治疗前ADC、Kep、Ve、Ktrans及其联合检测用于预测LARC新辅助治疗后pCR的曲线下面积（AUC）分别为0.667、0.511、0.797、0.666、0.880，敏感度分别为76.32%、78.95%、68.42%、73.68、81.58，特异性分别为75.61%、78.05%、70.73%、72.07%、86.59%，治疗前ADC、Kep、Ve、Ktrans的AUC最大且敏感度和特异性最高（P<0.05）。

DWI联合DCE-MRI定量参数可有效预测LARC患者新辅助治疗后的pCR，联合检测可提高预测效能。

To explore the predictive value of quantitative parameters of diffusion- weighted imaging (DWI) combined with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for pathological complete response (pCR) in patients with locally advanced rectal cancer (LARC) after neoadjuvant therapy.

A retrospective analysis was conducted on the medical records of 120 patients with LARC admitted to Xidian Group Hospital from January 2022 to January 2025, tumor regression grade (TRG) was adopted, TRG grade 0 was defined as the pCR group (n=38), and the rest were defined as the non-PCR group (n=82). The quantitative parameters of apparent diffusion coefficient (ADC), transport constant (Ktrans), percentage of extracellular space volume outside the blood vessels (Ve), and rate constant (Kep) before and after neoadjuvant therapy were compared between the two groups. Spearman correlation analysis was used to analyze the correlation between quantitative parameters of DWI and DCE-MRI and pCR after neoadjuvant therapy for LARC. ROC curve was used to analyze the predictive value of DWI combined with quantitative parameters of DCE-MRI before treatment for pCR after neoadjuvant therapy for LARC.

After treatment, the ADC of patients in the pCR group was higher than that in the non-pCR group, while Kep, Ve and Ktran were all lower than those in the non-pCR group (P<0.05). The results of Spearman correlation analysis showed that ADC before treatment was positively correlated with pCR after neoadjuvant therapy for LARC, while Kep, Ve, and Ktrans were all negatively correlated with pCR after neoadjuvant therapy for LARC (P<0.05). ROC curve analysis indicated that the areas under the curve (AUC) of ADC, Kep, Ve, Ktrans and their combined detections before treatment for predicting pCR after neoadjuvant therapy for LARC were 0.667, 0.511, 0.797, 0.666 and 0.880, respectively. The sensitivities were 76.32%, 78.95%, 68.42%, 73.68%, and 81.58% respectively, and the specificities were 75.61%, 78.05%, 70.73%, 72.07%, and 86.59% respectively. Before treatment, the AUC of ADC, Kep, Ve, and Ktrans was the largest, and their sensitivity and specificity were also the highest (P<0.05).

The quantitative parameters of DWI combined with DCE-MRI can effectively predict pCR in patients with LARC after neoadjuvant therapy, and the combined detection can improve the predictive efficacy.