Dataset Information

A role for dynamic contrast-enhanced magnetic resonance imaging in predicting tumour radiation response.

ABSTRACT:

Background

Dynamic contrast-enhanced (DCE) MRI may provide prognostic insights into tumour radiation response. This study examined quantitative DCE MRI parameters in rat tumours, as potential biomarkers of tumour growth delay following single high-dose irradiation.

Methods

Dunning R3327-AT1 prostate tumours were evaluated by DCE MRI following intravenous injection of Gd-DTPA. The next day tumours were irradiated (single dose of 30 Gy), while animals breathed air (n=4) or oxygen (n=4); two animals were non-irradiated controls. Growth was followed and tumour volume-quadrupling time (T4) was compared with pre-irradiation DCE assessments.

Results

Irradiation caused significant tumour growth delay (T4 ranged from 28 to 48 days for air-breathing rats, and 40 to 75 days for oxygen-breathing rats) compared with the controls (T4=7 to 9 days). A strong correlation was observed between T4 and extravascular-extracellular volume fraction (ve) irrespective of the gas inhaled during irradiation. There was also a correlation between T4 and volume transfer constant (K(trans)) for the air-breathing group alone.

Conclusions

The data provide rationale for expanded studies of other tumour sites, types and progressively patients, and are potentially significant, as many patients undergo contrast-enhanced MRI as part of treatment planning.

SUBMITTER: Hallac RR

PROVIDER: S-EPMC4891499 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Publications

A role for dynamic contrast-enhanced magnetic resonance imaging in predicting tumour radiation response.

Hallac Rami R RR Zhou Heling H Pidikiti Rajesh R Song Kwang K Solberg Timothy T Kodibagkar Vikram D VD Peschke Peter P Mason Ralph P RP

British journal of cancer 20160503 11

<h4>Background</h4>Dynamic contrast-enhanced (DCE) MRI may provide prognostic insights into tumour radiation response. This study examined quantitative DCE MRI parameters in rat tumours, as potential biomarkers of tumour growth delay following single high-dose irradiation.<h4>Methods</h4>Dunning R3327-AT1 prostate tumours were evaluated by DCE MRI following intravenous injection of Gd-DTPA. The next day tumours were irradiated (single dose of 30 Gy), while animals breathed air (n=4) or oxygen (n ...[more]

PMID: 27140315

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Dataset Information

A role for dynamic contrast-enhanced magnetic resonance imaging in predicting tumour radiation response.

Background

Methods

Results

Conclusions

Publications

A role for dynamic contrast-enhanced magnetic resonance imaging in predicting tumour radiation response.

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