NI-31 * USING TUMOR LOCALIZATION MAPS TO IDENTIFY BRAIN LOCATIONS INVOLVED IN COGNITIVE FUNCTIONING IN GLIOMA PATIENTS BEFORE THERAPY

Abstract

BACKGROUND: Cognition is often affected in patients with brain tumors. Apart from language function, direct tumor effects on discrete cognitive functions have barely been studied. In this study, we quantify baseline cognitive functioning in seven cognitive domains and identify brain locations involved in these cognitive domains using tumor localization maps (TLMs), which is a new approach. METHODS: Adult patients with glioma treated at the VU University Medical Center between 2006-2011 with available preoperative neuropsychological assessment were included. Cognition was tested for verbal, visuospatial and working memory, attention, executive functioning, information processing speed, and visuoconstructive abilities. Cognitive performance was compared to matched healthy controls. Tumor volumes for TLMs were segmented on MRI fluid attenuated inversion recovery (FLAIR) hyperintense signal abnormality for low-grade gliomas, and MRI T1 contrast-enhanced abnormality for high-grade gliomas. For each cognitive domain, we applied TLMs to link cognitive performance with location throughout the brain at 1 mm resolution. Considerations for spatial dependence and multiple comparisons were taken into account. PRELIMINARY RESULTS: Seventy-four patients (50 with low-grade glioma, 22 with high-grade glioma and 2 with other histology) were included so far. Mean age of patients was 40 years. Compared to healthy controls, preoperative cognitive functioning was significantly impaired in five of seven domains. Most frequently affected were attention and working memory (30% and 21% of patients, respectively). We found no differences in cognitive domain scores between patients with low-grade and high-grade glioma. Tumor localization maps are currently being processed and statistically compared voxel-wise for each of the seven cognitive domains. Preliminary results of the TLMs demonstrate that performance in specific cognitive domains is associated with specific brain tumor locations. CONCLUSION: Empirical evidence on location of cognition can be used for optimizing brain tumor surgery and be integrated in counseling and cognitive rehabilitation for patients with newly-diagnosed glioma.