Abstract B044: Dosimetric association between critical brain structure dose and scholastic achievement in pediatric brain tumor survivors
Authors: Mailhot Vega Raymond B. , Indelicato Daniel J. , Bradley Julie A. , Mobley Erin M. , Morris Christopher G. , Fisher Carla L. , Markatia Adeel , Ramahi Yousef , Mendenhall Nancy P. , Crisp Amy M. , Miller M. David 
Published: September 2024

Abstract
Purpose: Radiotherapy (RT) causes cognitive deficits in pediatric brain tumor survivors (PBTS). Cognitive deficits have traditionally been measured using exams such as serial IQ tests administered after diagnosis. Scholastic data captures a student’s academic achievement before, during, and after their cancer diagnosis and treatment and is practical for patients and families. Poor educational performance is associated with worse health, higher risk of incarceration, and a higher risk of experiencing future poverty, and educational achievement disparities burdening Black and Hispanic American public school students are well documented. We sought to evaluate the association between dose to brain organs at risk (OARs) historically associated with cognitive decrement and scholastic achievement in PBTS pre- and post-RT.Materials/Methods: With Institutional Review Board approval, we retrospectively analyzed scholastic achievement in PBTS treated with RT at our institution for this pilot. Eligible PBTS all resided within the state of the institution and were treated from 2007-2021. The state’s Department of Education provided scholastic data for grade promotion, transcripts, accommodations, and state-mandated assessments of mathematics and reading in grades 3-11, which were merged with institutional clinical data. Dependent variables of interest were accommodations, grade promotion, and satisfactory performance on state mandated exams. A general linear mixed-effects model assessed the above scholastic dependent variables from the pre- and post-treatment phase and the independent variables of mean OAR dose to the hippocampus (H), corpus callosum (CC), and frontal lobe (FL), volume receiving X Gy dose to an OAR in 5 Gy increments (e.g., V5, V10) to V40 , and an interaction term of the independent variable and time (pre or post-radiotherapy) was the variable of interest, with α=0.1.Results: Fifty PBTS were included in the sample with a median age of 11.6 years at treatment and 7 years of follow-up. Overall, 52% were eligible for free or reduced lunch, and 56% received craniospinal irradiation. V5, V10, V15, and V20 to H. and FL were associated with math performance, and V25, V30, V35, and V40 to FL were associated with reading performance. For each of these models, the estimated change in scholastic outcome was calculated for post-treatment and a 1% increase in volume receiving the dose, all of which showed a decrease in scholastic outcome. There was no dosimetric association between dose and scholastic performance for CC. Conclusions: We present the first report evaluating associations between dosimetry and scholastic performance. Our work identifies an association between H. dose and reading performance and FL dose and math and reading performance on mandated annual state exams. Evaluating scholastic success is an unmet need for PBTS. We demonstrate a novel method using scholastic performance data as a patient-centered metric, leveraging prospectively collected scholastic outcomes already recorded by states.
Citation Format: Raymond B. Mailhot Vega, Daniel J. Indelicato, Julie A. Bradley, Erin M. Mobley, Christopher G. Morris, Carla L. Fisher, Adeel Markatia, Yousef Ramahi, Nancy P. Mendenhall, Amy M. Crisp, M. David Miller. Dosimetric association between critical brain structure dose and scholastic achievement in pediatric brain tumor survivors [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pediatric Cancer Research; 2024 Sep 5-8; Toronto, Ontario, Canada. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl):Abstract nr B044.