Abstract B39: A pilot study of neuropsychological functions, APOE, and amyloid imaging in patients with gliomas

Patients with brain tumors treated with radiotherapy (RT) often develop cognitive dysfunction, and recent studies suggest that the apolipoprotein (APOE) ϵ-4 allele may influence cognitive outcome. The ϵ-4 allele promotes beta (β) amyloid deposition in the cortex, and preliminary evidence suggests that RT may be associated with β-amyloid deposition. In this pilot study, we assessed neuropsychological functions and β-amyloid retention using 18F-florbetaben PET in a subset of brain tumor patients who participated in our study of APOE polymorphisms and cognitive functions. Twenty glioma patients treated with conformal RT ± chemotherapy participated in the study: 6 were APOE ϵ-4 carriers and 14 were non-ϵ-4 carriers. Patients completed a neuropsychological reevaluation and brain MRI and 18F-florbetaben PET scans. The results of Wilcoxon rank sums test comparisons between prior and current assessments showed a significant decline in selective attention (Brief Test of Attention, p=0.018), and a near-significant decline in verbal learning (Hopkins Verbal Learning Test-Learning, p=0.07). Comparisons between assessments by APOE status showed a significant decline in attention and working memory (WAIS-III digits forward, p=0.028 and digits backward, p=0.032) among APOE ϵ-4 carriers. Comparisons of PET regional standard uptake value ratios (SUVRs) showed near-significant differences for the medial temporal cortex (p=0.069) and the putamen (p=0.069), with non-ϵ-4 carriers having higher SUVRs. The findings suggest that glioma patients may experience progressive worsening in attention and executive functions several years after treatment with RT ± chemotherapy, and that the APOE ϵ-4 allele may moderate cognitive decline. Note: This abstract was not presented at the conference. Citation Format: Denise Correa, Maria Kryza-Lacombe, Xiaosun Zhou, Raymond Baser, Brad Beattie, Zodina Beiene, Irene Orlow, John Humm, Lisa DeAngelis, Wolfgang Weber, Joseph Osborne. A pilot study of neuropsychological functions, APOE, and amyloid imaging in patients with gliomas [abstract]. In: Proceedings of the Tenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2017 Sep 25-28; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2018;27(7 Suppl):Abstract nr B39.