Department of Radiology and Nuclear Medicine, Amsterdam UMC, Cancer Center Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands. Department of Pediatric Hematology and Oncology, University of Toronto, Toronto, ON, Canada. Department of Ophthalmology and Vision Science, University of Toronto, Toronto, ON, Canada. Department of Ophthalmology and Vision Science, The Hospital for Sick Children, Toronto, ON, Canada. Department of Pediatric Oncology, Amsterdam UMC, Cancer Center Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands. Department of Clinical Genetics, Amsterdam UMC, Cancer Center Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands. Department of Ophthalmology, Amsterdam UMC, Cancer Center Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands. Child Health Evaluative Sciences Program, SickKids Research Institute, Toronto, ON, Canada. Division of Clinical Public Health, Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada. Division of Pediatric Neuroradiology, The Hospital of Sick Children, Toronto, ON, Canada. Department of Ophthalmology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland. Department of Ophthalmology and Vision Science, Ocular Oncology service, Princess Margaret Hospital, Toronto, ON, Canada. Faculty of Medicine, Department of Ophthalmology, University of Alexandria, Alexandria, Egypt.