Zhang Guangwen, Xu Ziliang, Zheng Jianyong, Wang Mian, Ren Jialiang, Wei Xiaocheng, Huan Yi, Zhang Jinsong
Department of Radiology, Xijing Hospital, Fourth Military Medical University, No.127, Chang Le West Road, Xi'an, 710032, Shaanxi, China.
Department of Gastrointestinal Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
Eur Radiol. 2023 Mar;33(3):1928-1937. doi: 10.1007/s00330-022-09159-7. Epub 2022 Oct 11.
To evaluate the potential of multi b-value DWI in predicting the prognosis of patients with locally advanced rectal cancer (LARC).
From 2015 to 2019, a total of 161 patients with LARC were enrolled and randomly sampled into a training set (n = 113) and validation set (n = 48). Multi b-value DWI (b = 0~1500 s/mm) scans were postprocessed to generate functional parameters, including apparent diffusion coefficient (ADC), Dt, Dp, f, distributed diffusion coefficient (DDC), and α. Histogram features of each functional parameter were submitted into Least absolute shrinkage and selection operator (LASSO) and stepwise multivariate COX analysis to generate DWI_score based on the training set. The prognostic model was constructed with functional parameter, DWI_score, and clinicopathologic factors by using univariate and multivariate COX analysis on the training set and verified on the validation set.
Multivariate COX analysis revealed that DWI_score was an independent indicator for 5-year progression-free survival (PFS, HR = 5.573, p < 0.001), but not for overall survival (OS, HR = 2.177, p = 0.051). No mean value of functional parameters was correlated with PFS or OS. Prognostic model for 5-year PFS based on DWI_score, TNM-stage, mesorectal fascia (MRF), and extramural venous invasion (EMVI) showed good performance both in the training set (AUC = 0.819) and validation set (AUC = 0.815).
The DWI_score based on histogram features of multi b-value DWI functional parameters was an independent factor for PFS of LARC and the prognostic model with a combination of DWI_score and clinicopathologic factors could indicate the progression risk before treatment.
• Mean value of functional parameters obtained from multi b-value DWI might not be useful to assess the prognosis of LARC. • The DWI_score based on histogram features of multi b-value DWI functional parameters was an independent prognosis factor for PFS of LARC. • Prognostic model based on DWI_score and clinicopathologic factors could indicate the progression risk of LARC before treatment.
评估多b值扩散加权成像（DWI）预测局部晚期直肠癌（LARC）患者预后的潜力。
2015年至2019年，共纳入161例LARC患者，并随机分为训练集（n = 113）和验证集（n = 48）。对多b值DWI（b = 0~1500 s/mm²）扫描进行后处理以生成功能参数，包括表观扩散系数（ADC）、Dt、Dp、f、分布扩散系数（DDC）和α。将每个功能参数的直方图特征纳入最小绝对收缩和选择算子（LASSO）及逐步多变量COX分析，以基于训练集生成DWI评分。通过对训练集进行单变量和多变量COX分析，构建包含功能参数、DWI评分和临床病理因素的预后模型，并在验证集上进行验证。
多变量COX分析显示，DWI评分是5年无进展生存期（PFS）的独立指标（HR = 5.573，p < 0.001），但不是总生存期（OS）的独立指标（HR = 2.177，p = 0.051）。功能参数的平均值与PFS或OS均无相关性。基于DWI评分、TNM分期、直肠系膜筋膜（MRF）和壁外静脉侵犯（EMVI）构建的5年PFS预后模型在训练集（AUC = 0.819）和验证集（AUC = 0.815）中均表现良好。
基于多b值DWI功能参数直方图特征的DWI评分是LARC患者PFS的独立因素，结合DWI评分和临床病理因素的预后模型可在治疗前提示进展风险。
• 多b值DWI获得的功能参数平均值可能对评估LARC患者的预后无用。• 基于多b值DWI功能参数直方图特征的DWI评分是LARC患者PFS的独立预后因素。• 基于DWI评分和临床病理因素的预后模型可提示LARC患者治疗前的进展风险。
