Multi-parametric magnetic resonance imaging assessment of whole tumour heterogeneity for chemoradiotherapy response prediction in rectal cancer

Trang Thanh Pham; Gary Liney; Karen Wong; Christopher Henderson; Robba Rai; Petra L Graham; Nira Borok; Minh Xuan Truong; Mark Lee; Joo-Shik Shin; Malcolm Hudson; Michael B Barton

doi:10.1016/j.phro.2021.03.003

Multi-parametric magnetic resonance imaging assessment of whole tumour heterogeneity for chemoradiotherapy response prediction in rectal cancer

Phys Imaging Radiat Oncol. 2021 Apr 13:18:26-33. doi: 10.1016/j.phro.2021.03.003. eCollection 2021 Apr.

Authors

Trang Thanh Pham^{1

2}, Gary Liney¹, Karen Wong², Christopher Henderson³, Robba Rai², Petra L Graham⁴, Nira Borok⁵, Minh Xuan Truong⁵, Mark Lee², Joo-Shik Shin^{3

6}, Malcolm Hudson⁷, Michael B Barton¹

Affiliations

¹ 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.
² Department of Radiation Oncology, Liverpool Cancer Therapy Centre, Liverpool Hospital, Sydney, Locked Bag 7103, Liverpool BC, NSW 1871, Australia.
³ Department of Anatomical Pathology, Liverpool Hospital, Sydney, Locked Bag 7103, Liverpool BC, NSW, 1871, Australia.
⁴ Centre for Economic Impacts of Genomic Medicine, Macquarie Business School and Department of Mathematics and Statistics, Faculty of Science and Engineering, Macquarie University, Sydney, Macquarie University, NSW 2109, Australia.
⁵ Department of Radiology, Liverpool Hospital, Sydney, Locked Bag 7103, Liverpool BC, NSW 1871, Australia.
⁶ School of Medicine, Western Sydney University, Sydney, Locked Bag 1797, Penrith, NSW 2751, Australia.
⁷ NHMRC Clinical Trials Centre, Sydney, Locked Bag 77, Camperdown, NSW 1450, Australia.

Abstract

Background and purpose: 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.

Materials and methods: 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^trans (Tofts model) histograms derived from DWI and DCE-MRI, respectively. Logistic regression was used to predict response status for ADC and K^trans quantiles.

Results: 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^trans 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).

Conclusions: 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.

Clinical trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR) number ACTRN12616001690448.