Pham Trang Thanh, Liney Gary, Wong Karen, Henderson Christopher, Rai Robba, Graham Petra L, Borok Nira, Truong Minh Xuan, Lee Mark, Shin Joo-Shik, Hudson Malcolm, Barton Michael B
Ingham Institute for Applied Medical Research, South West Sydney Clinical School, Faculty of Medicine, University of New South Wales, Sydney, PO Box 3151, Liverpool, NSW 2170, Australia.
Department of Radiation Oncology, Liverpool Cancer Therapy Centre, Liverpool Hospital, Sydney, Locked Bag 7103, Liverpool BC, NSW 1871, Australia.
Phys Imaging Radiat Oncol. 2021 Apr 13;18:26-33. doi: 10.1016/j.phro.2021.03.003. eCollection 2021 Apr.
Prediction of chemoradiotherapy response (CRT) in locally advanced rectal cancer would enable stratification of management. The purpose was to prospectively evaluate multi-parametric magnetic resonance imaging (MRI) assessment of tumour heterogeneity combining diffusion weighted imaging (DWI) and dynamic contrast enhanced (DCE) MRI for the prediction of CRT response in locally advanced rectal cancer.
Patients with Stage II or III rectal adenocarcinoma undergoing neoadjuvant CRT and surgery underwent MRI (DWI and DCE) before, during (week 3), and after CRT (1 week before surgery). Patients with histopathology tumour regression grade (TRG) 0-1 were classified as responders, and TRG 2-3 were classified as non-responders. A whole tumour voxel-wise technique was used to produce apparent diffusion coefficient (ADC) and K (Tofts model) histograms derived from DWI and DCE-MRI, respectively. Logistic regression was used to predict response status for ADC and K quantiles.
Thirty-three patients were included in this analysis; 16 responders, and 17 non-responders. On heterogeneity analysis, odds of being a responder were significantly higher after CRT (before surgery) for higher ADC 75th (p = 0.049) and ADC 90th (p = 0.034) percentile values. The K quantiles were lower in non-responders than responders before and during CRT, and higher after CRT although no significant association with response status was observed (p ≥ 0.10).
DWI-MRI after CRT (before surgery) incorporating a histogram analysis of whole tumour heterogeneity was predictive of CRT response in patients with locally advanced rectal cancer. DCE-MRI did not add value in response prediction.
Australian New Zealand Clinical Trials Registry (ANZCTR) number ACTRN12616001690448.
预测局部晚期直肠癌的放化疗反应（CRT）有助于分层管理。本研究旨在前瞻性评估多参数磁共振成像（MRI）对肿瘤异质性的评估，结合扩散加权成像（DWI）和动态对比增强（DCE）MRI，以预测局部晚期直肠癌的CRT反应。
接受新辅助CRT和手术的II期或III期直肠腺癌患者在CRT前、期间（第3周）和CRT后（手术前1周）接受MRI（DWI和DCE）检查。组织病理学肿瘤退缩分级（TRG）为0-1的患者被归类为反应者，TRG为2-3的患者被归类为无反应者。采用全肿瘤体素技术分别生成源自DWI和DCE-MRI的表观扩散系数（ADC）和K（Tofts模型）直方图。使用逻辑回归预测ADC和K分位数的反应状态。
本分析纳入33例患者；16例反应者和17例无反应者。在异质性分析中，CRT后（手术前）ADC第75百分位数（p = 0.049）和ADC第90百分位数（p = 0.034）较高时，成为反应者的几率显著更高。在CRT前和期间，无反应者的K分位数低于反应者，CRT后更高，尽管未观察到与反应状态有显著关联（p≥0.10）。
CRT后（手术前）的DWI-MRI结合全肿瘤异质性直方图分析可预测局部晚期直肠癌患者的CRT反应。DCE-MRI在反应预测中未增加价值。
澳大利亚和新西兰临床试验注册中心（ANZCTR）编号ACTRN12616001690448。
