Dataset Information

Improving Delineation of True Tumor Volume With Multimodal MRI in a Rat Model of Brain Metastasis.

ABSTRACT:

Purpose

Brain metastases are almost universally lethal with short median survival times. Despite this, they are often potentially curable, with therapy failing only because of local relapse. One key reason relapse occurs is because treatment planning did not delineate metastasis margins sufficiently or accurately, allowing residual tumor to regrow. The aim of this study was to determine the extent to which multimodal magnetic resonance imaging (MRI), with a simple and automated analysis pipeline, could improve upon current clinical practice of single-modality, independent-observer tumor delineation.

Methods and materials

We used a single rat model of brain metastasis (ENU1564 breast carcinoma cells in BD-IX rats), with and without radiation therapy. Multimodal MRI data were acquired using sequences either in current clinical use or in clinical trial and included postgadolinium T₁-weighted images and maps of blood flow, blood volume, T₁ and T₂ relaxation times, and apparent diffusion coefficient.

Results

In all cases, independent observers underestimated the true size of metastases from single-modality gadolinium-enhanced MRI (85 ± 36 ?L vs 131 ± 40 ?L histologic measurement), although multimodal MRI more accurately delineated tumor volume (132 ± 41 ?L). Multimodal MRI offered increased sensitivity compared with independent observer for detecting metastasis (0.82 vs 0.61, respectively), with only a slight decrease in specificity (0.86 vs 0.98). Blood flow maps conferred the greatest improvements in margin detection for late-stage metastases after radiation therapy. Gadolinium-enhanced T₁-weighted images conferred the greatest increase in accuracy of detection for smaller metastases.

Conclusions

These findings suggest that multimodal MRI of brain metastases could significantly improve the visualization of brain metastasis margins, beyond current clinical practice, with the potential to decrease relapse rates and increase patient survival. This finding now needs validation in additional tumor models or clinical cohorts.

SUBMITTER: Larkin JR

PROVIDER: S-EPMC7082766 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Publications

Improving Delineation of True Tumor Volume With Multimodal MRI in a Rat Model of Brain Metastasis.

Larkin James R JR Simard Manon A MA de Bernardi Axel A Johanssen Vanessa A VA Perez-Balderas Francisco F Sibson Nicola R NR

International journal of radiation oncology, biology, physics 20200117 5

<h4>Purpose</h4>Brain metastases are almost universally lethal with short median survival times. Despite this, they are often potentially curable, with therapy failing only because of local relapse. One key reason relapse occurs is because treatment planning did not delineate metastasis margins sufficiently or accurately, allowing residual tumor to regrow. The aim of this study was to determine the extent to which multimodal magnetic resonance imaging (MRI), with a simple and automated analysis ...[more]

PMID: 31959544

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Dataset Information

Improving Delineation of True Tumor Volume With Multimodal MRI in a Rat Model of Brain Metastasis.

Purpose

Methods and materials

Results

Conclusions

Publications

Improving Delineation of True Tumor Volume With Multimodal MRI in a Rat Model of Brain Metastasis.

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