RO-06. INCIDENCE OF CATARACT DEVELOPMENT IN PEDIATRIC PATIENTS RECEIVING CRANIOSPINAL IRRADIATION Ros Whelan, Todd Hankinson, Kathleen Dorris, Benjamin Saccomano, Michael Handler, Arthur Liu, Molly Hemenway, and Jennifer Madden; Children’s Hospital Colorado, Aurora, CO, USA OBJECTIVE: Craniospinal irradiation (CSI) is an important component of therapy for some children with brain tumors. CSI has been associated with numerous late effects, but there is a paucity of data regarding cataract development following CSI. We investigated the incidence of cataracts in children treated at our institution. METHODS: Single center retrospective analysis of children with primary intracranial neoplasms who received CSI between 07/2007 and 06/2015. Data included tumor histologyand location, radiation dose, cataract development and intervention. RESULTS: Sixty-five children received CSI over that time period (57 embryonal tumors, 5 germ cell tumors, 3 pineal tumors) and 46 had eye exams. Median CSI dose was 23.4 Gy (range 12 36 Gy). With a median follow up of 25.0 months, thirteen (28%) developed cataracts with a median time to develop cataracts of 27.6 months (range 20-60 months). Six have required intervention. CONCLUSIONS: Development of cataracts is a significant risk in children who require CSI for the treatment of a brain tumor. Routine eye exams should be included with long term follow-up. Further study will better delineate risk factors for the development of cataracts, allowing appropriate screening and management for these patients. Neuro-Oncology 18:iii159–iii164, 2016. doi:10.1093/neuonc/now082.6 #The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.