Open AccessArticle
Quantifying Tumor Heterogeneity via MRI Habitats to Characterize Microenvironmental Alterations in HER2+ Breast Cancer
by
1
, 2,3
, 4, 4, 4, 4, 3,5,6
, 2,3,4,5,6,7,*
and 8,9,10,*
1
Department of Radiology, The University of Washington, Seattle, WA 98104, USA
2
Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712, USA
3
Livestrong Cancer Institutes, The University of Texas at Austin, Austin, TX 78712, USA
4
Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
5
Department of Diagnostic Medicine, The University of Texas at Austin, Austin, TX 78712, USA
6
Department of Oncology, The University of Texas at Austin, Austin, TX 78712, USA
7
Department of Imaging Physics, MD Anderson Cancer Center, The University of Texas, Houston, TX 77030, USA
8
Department of Biomedical Engineering, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
9
Department of Radiology, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
10
O’Neal Comprehensive Cancer Center, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
*
Authors to whom correspondence should be addressed.
Academic Editor: David Wong
Received: 9 February 2022
/
Revised: 2 April 2022
/
Accepted: 2 April 2022
/
Published: 6 April 2022
Simple Summary
Tumor heterogeneity influences tumor progression and response to therapy, introducing a significant challenge in the treatment of breast cancer. We employed magnetic resonance imaging (MRI) to characterize tumor heterogeneity over time in response to treatment in a mouse model of HER2+ breast cancer. In a two-part approach, we first used quantitative MRI to identify unique subregions of the tumor (i.e., “tumor habitats”, resolving intratumoral heterogeneity), then used the habitats to stratify tumors prior to treatment into two distinct “tumor imaging phenotypes” (resolving intertumoral heterogeneity). The tumor phenotypes exhibited differential response to treatments, suggesting that baseline phenotypes can predict therapy response. Additionally, there were significant correlations between the imaging habitats and histological measures of vascular maturation, hypoxia, and macrophage infiltration, lending ex vivo biological validation to the in vivo imaging habitats. Application of these techniques in the clinical setting could improve understanding of an individual patient’s tumor pathology and potential therapeutic sensitivity.