Dataset Information

Mapping early tumor response to radiotherapy using diffusion kurtosis imaging*.

ABSTRACT:

Purpose

In this pilot study, DKI measures of diffusivity and kurtosis were compared in active tumor regions and correlated to radiologic response to radiotherapy after completion of 2 weeks of treatment to derive potential early measures of tumor response.

Methods

MRI and Magnetic Resonance Spectroscopic Imaging (MRSI) data were acquired before the beginning of RT (pre-RT) and 2 weeks after the initiation of treatment (during-RT) in 14 glioblastoma patients. The active tumor region was outlined as the union of the residual contrast-enhancing region and metabolically active tumor region. Average and standard deviation of mean, axial, and radial diffusivity (MD, AD, RD) and mean, axial, and radial kurtosis (MK, AK, RK) values were calculated for the active tumor VOI from images acquired pre-RT and during-RT and paired t-tests were executed to estimate pairwise differences. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the predictive capabilities of changes in diffusion metrics for progression-free survival (PFS).

Results

Analysis showed significant pairwise differences for AD (p = 0.035; Cohen's d of 0.659) and AK (p = 0.019; Cohen's d of 0.753) in diffusion measures after 2 weeks of RT. ROC curve analysis showed that percentage change differences in AD and AK between pre-RT and during-RT scans provided an Area Under the Curve (AUC) of 0.524 and 0.762, respectively, in discriminating responders (PFS>180 days) and non-responders (PFS<180 days).

Conclusion

This pilot study, although preliminary in nature, showed significant changes in AD and AK maps, with kurtosis derived AK maps showing an increased sensitivity in mapping early changes in the active tumor regions.

SUBMITTER: Goryawala M

PROVIDER: S-EPMC10034702 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Publications

Mapping early tumor response to radiotherapy using diffusion kurtosis imaging*.

Goryawala Mohammed M Mellon Eric A EA Shim Hyunsuk H Maudsley Andrew A AA

The neuroradiology journal 20220824 2

<h4>Purpose</h4>In this pilot study, DKI measures of diffusivity and kurtosis were compared in active tumor regions and correlated to radiologic response to radiotherapy after completion of 2 weeks of treatment to derive potential early measures of tumor response.<h4>Methods</h4>MRI and Magnetic Resonance Spectroscopic Imaging (MRSI) data were acquired before the beginning of RT (pre-RT) and 2 weeks after the initiation of treatment (during-RT) in 14 glioblastoma patients. The active tumor regio ...[more]

PMID: 36000488

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Dataset Information

Mapping early tumor response to radiotherapy using diffusion kurtosis imaging*.

Purpose

Methods

Results

Conclusion

Publications

Mapping early tumor response to radiotherapy using diffusion kurtosis imaging*.

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