Microstructural injury to left-sided perisylvian white matter predicts language decline after brain radiation therapy Journal Article

Authors: Tibbs, M. D.; Huynh-Le, M. P.; Karunamuni, R.; Reyes, A.; Macari, A. C.; Tringale, K. R.; Salans, M.; Yip, A.; Liu, E.; Simon, A.; McDonald, C. R.; Hattangadi-Gluth, J. A.
Article Title: Microstructural injury to left-sided perisylvian white matter predicts language decline after brain radiation therapy
Abstract: Purpose: Our purpose was to investigate the association between imaging biomarkers of radiation-induced white matter (WM) injury within perisylvian regions and longitudinal language decline in patients with brain tumors. Methods and Materials: Patients with primary brain tumors (n = 44) on a prospective trial underwent brain magnetic resonance imaging, diffusion-weighted imaging, and language assessments of naming (Boston Naming Test [BNT]) and fluency (Delis–Kaplan Executive Function System Category Fluency [DKEFS-CF]) at baseline and 3, 6, and 12 months after fractionated radiation therapy (RT). Reliable change indices of language function (0-6 months), accounting for practice effects (RCI-PE), evaluated decline. Bilateral perisylvian WM regions (superficial WM subadjacent to Broca's area and the superior temporal gyrus [STG], inferior longitudinal fasciculus [ILF], inferior fronto-occipital fasciculus [IFOF], and arcuate fasciculus) were autosegmented. We quantified volume and diffusion measures of WM microstructure: fractional anisotropy (FA; lower values indicate disruption) and mean diffusivity (MD; higher values indicate injury). Linear mixed-effects models assessed mean dose as predictor of imaging biomarker change and imaging biomarkers as longitudinal predictors of language scores. Results: DKEFS-CF scores declined at 6 months post-RT (RCI-PE, -0.483; P = .01), whereas BNT scores improved (RCI-PE, 0.262; P = .04). Higher mean dose to left and right regions was predictive of decreased volume (left-STG, P = .02; right-ILF and IFOF, P = .03), decreased FA (left-WM tracts, all P < .01; right-STG and IFOF, P < .02), and increased MD of left-WM tracts (all P < .03). Volume loss within left-Broca's area (P = .01), left-ILF (P = .01), left-IFOF (P = .01), and left-arcuate fasciculus (P = .04) was associated with lower BNT scores. Lower FA correlated with poorer DKEFS-CF and BNT scores within left-ILF (P = .02, not significant), left-IFOF (P = .02, .04), and left-arcuate fasciculus (P = .01, .01), respectively. Poorer DKEFS-CF scores correlated with increased MD values within the left-arcuate fasciculus (P = .03). Right-sided biomarkers did not correlate with language scores. Conclusions: Patients with primary brain tumors experience language fluency decline post-RT. Poorer fluency and naming function may be explained by microstructural injury to left-sided perisylvian WM, representing potential dose-avoidance targets for language preservation. © 2020 Elsevier Inc.
Keywords: magnetic resonance imaging; biomarkers; radiotherapy; brain; tumors; diffusion weighted imaging; fractional anisotropy; primary brain tumors; methods and materials; fractionated radiation; superior temporal gyrus; linear mixed-effects model; language assessment
Journal Title: International Journal of Radiation Oncology, Biology, Physics
Volume: 108
Issue: 5
ISSN: 0360-3016
Publisher: Elsevier Inc.  
Date Published: 2020-12-01
Start Page: 1218
End Page: 1228
Language: English
DOI: 10.1016/j.ijrobp.2020.07.032
PUBMED: 32712255
PROVIDER: scopus
PMCID: PMC7680351
Notes: Article -- Export Date: 1 December 2020 -- Source: Scopus
Citation Impact
MSK Authors