Serial MR diffusion to predict treatment response in high-grade pediatric brain tumors: a comparison of regional and voxel-based diffusion change metrics

Rodriguez Gutierrez, D.; Manita, M.; Jaspan, T.; Dineen, Robert A.; Grundy, Richard G.; Auer, Dorothee P.

Abstract

Background

Assessment of treatment response by measuring tumor size is known to be a late and potentially confounded response index. Serial diffusion MRI has shown potential for allowing earlier and possibly more reliable response assessment in adult patients, with limited experience in clinical settings and in pediatric brain cancer. We present a retrospective study of clinical MRI data in children with high-grade brain tumors to assess and compare the values of several diffusion change metrics to predict treatment response.

Methods

Eighteen patients (age range, 1.9–20.6 years) with high-grade brain tumors and serial diffusion MRI (pre- and posttreatment interval range, 1–16 weeks posttreatment) were identified after obtaining parental consent. The following diffusion change metrics were compared with the clinical response status assessed at 6 months: (1) regional change in absolute and normalized apparent diffusivity coefficient (ADC), (2) voxel-based fractional volume of increased (fiADC) and decreased ADC (fdADC), and (3) a new metric based on the slope of the first principal component of functional diffusion maps (fDM).

Results

Responders (n = 12) differed significantly from nonresponders (n = 6) in all 3 diffusional change metrics demonstrating higher regional ADC increase, larger fiADC, and steeper slopes (P < .05). The slope method allowed the best response prediction (P < .01, η2 = 0.78) with a classification accuracy of 83% for a slope of 58° using receiver operating characteristic (ROC) analysis.

Conclusions

We demonstrate that diffusion change metrics are suitable response predictors for high-grade pediatric tumors, even in the presence of variable clinical diffusion imaging protocols.

Citation

Rodriguez Gutierrez, D., Manita, M., Jaspan, T., Dineen, R. A., Grundy, R. G., & Auer, D. P. (in press). Serial MR diffusion to predict treatment response in high-grade pediatric brain tumors: a comparison of regional and voxel-based diffusion change metrics. Neuro-Oncology, 15(8), https://doi.org/10.1093/neuonc/not034

• Journal Article Type: Article
• Acceptance Date: Feb 15, 2013
• Online Publication Date: Apr 12, 2013
• Deposit Date: Nov 22, 2016
• Publicly Available Date: Nov 22, 2016
• Journal: Neuro-Oncology
• Print ISSN: 1522-8517
• Electronic ISSN: 1523-5866
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 15
• Issue: 8
• DOI: https://doi.org/10.1093/neuonc/not034
• Keywords: ADC, fDM, Pediatric tumor, Response prediction, Serial diffusion.
• Public URL: https://nottingham-repository.worktribe.com/output/714441
• Publisher URL: http://dx.doi.org/10.1093/neuonc/not034
• Contract Date: Nov 22, 2016