Chen Fangying, Zhang Shaoting, Fu Caixia, Grimm Robert, Lu Jianping, Shao Chengwei, Shen Fu, Chen Luguang
Department of Radiology, Changhai Hospital, Naval Medical University, NO.168 Changhai Road, Shanghai, 200433, China.
Department of Radiology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.
Jpn J Radiol. 2025 Feb;43(2):236-246. doi: 10.1007/s11604-024-01674-5. Epub 2024 Oct 21.
Disease-free survival (DFS) after neoadjuvant chemoradiotherapy (nCRT) is an important factor in affecting the quality of life and determining the subsequent treatment procedures for patients with locally advanced rectal cancer (LARC). This study aimed to develop a novel prognostic model for predicting the DFS in patients with LARC following nCRT and to verify its effectiveness.
Patients with LARC who underwent magnetic resonance imaging (MRI) and nCRT at our institution between November 2017 and March 2022 were enrolled in this retrospective study. Clinicopathologic data and MRI indicators of all patients were collected and evaluated. All patients were divided into DFS and non-DFS groups according to the presence or absence of local recurrence or distant metastasis. The differences in the b-value threshold (b) and apparent diffusion coefficient (ADC) values between the DFS and non-DFS groups were compared. The Cox analyses were used to determine the risk factors in predicting the DFS. A merged model was established based on the risk factors, and a nomogram was constructed. The predictive performances of the merged model were validated using the receiver-operating characteristic (ROC) and decision curve analysis (DCA).
Of the 524 patients enrolled, 132 who underwent surgical resection post-nCRT were included in the final analysis. The post-neoadjuvant therapy pathological N stage, extramural venous invasion (EMVI), and b were independent factors in predicting the DFS. The C-index of the model was 0.688. The area under the curve (AUC) of the nomogram in predicting the 1-, 3-, and 5-year survival rates of patients was 0.731, 0.723, and 0.779, respectively. The DCA demonstrated that the merged model had a greater advantage than either the "all" or the "none" scheme when the threshold probability was between 0.1 and 0.65.
A merged model based on the b value and clinicopathological features showed the potential to predict the prognosis of patients with LARC after nCRT and surgery.
新辅助放化疗（nCRT）后的无病生存期（DFS）是影响局部晚期直肠癌（LARC）患者生活质量和决定后续治疗方案的重要因素。本研究旨在建立一种预测LARC患者nCRT后DFS的新型预后模型并验证其有效性。
本回顾性研究纳入了2017年11月至2022年3月在我院接受磁共振成像（MRI）和nCRT的LARC患者。收集并评估所有患者的临床病理数据和MRI指标。根据是否存在局部复发或远处转移，将所有患者分为DFS组和非DFS组。比较DFS组和非DFS组之间的b值阈值（b）和表观扩散系数（ADC）值的差异。采用Cox分析确定预测DFS的危险因素。基于危险因素建立合并模型，并构建列线图。使用受试者操作特征（ROC）和决策曲线分析（DCA）验证合并模型的预测性能。
在纳入的524例患者中，132例nCRT后接受手术切除的患者纳入最终分析。新辅助治疗后病理N分期、壁外静脉侵犯（EMVI）和b是预测DFS的独立因素。模型的C指数为0.688。列线图预测患者1年、3年和5年生存率的曲线下面积（AUC）分别为0.731、0.723和0.779。DCA表明，当阈值概率在0.1至0.65之间时，合并模型比“全部”或“无”方案具有更大优势。
基于b值和临床病理特征的合并模型显示出预测LARC患者nCRT和手术后预后的潜力。
