Microstructural Injury to Left-Sided Perisylvian White Matter Predicts Language Decline After Brain Radiation Therapy.
Int J Radiat Oncol Biol Phys
; 108(5): 1218-1228, 2020 12 01.
Article
in En
| MEDLINE
| ID: mdl-32712255
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.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Radiation Injuries
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Brain Neoplasms
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Cranial Irradiation
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White Matter
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Language Disorders
Type of study:
Observational_studies
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Prognostic_studies
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Risk_factors_studies
Limits:
Adult
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Aged
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Female
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Humans
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Male
/
Middle aged
Language:
En
Journal:
Int J Radiat Oncol Biol Phys
Year:
2020
Document type:
Article