We thank the research coordinators and following physicians at pediatric cancer centers for contributing data to this project: Prashant Hiwarkar and Jayashree Motwani, Birmingham Women's and Children's Hospital, UK; Kelly Malone, Children's Hospital of Colorado, USA; Mylene Bassal, Children's Hospital of Eastern Ontario, Canada; Yoav Messinger and Joanna Perkins, Children's Hospital of Minnesota, USA; Van Huynh, Children's Hospital of Orange County, USA; Richard Ho, Children's Hospital at Vanderbilt, USA; Joanne Chuah and Jessa Morales, Children's Hospital at Westmead, Australia; Donald Wells, Dell Children's Hospital, USA; Nicolas Boissel, Hospital Saint-Louis, France; Tannie Huang, Kaiser Permanente, USA; Stacey Marjerrison, McMaster Children's Hospital, Canada; William Carroll and Joanna Pierro, New York University Langone Medical Center, USA; Ajay Vora, Sheffield Children's Hospital, UK; Donna Lancaster, The Royal Marsden Hospital, UK; Lucie Šrámková, University Hospital Motol, Czech Republic; Chatchawin Assanasen, University of Texas Health Science Center, San Antonio, USA; Rupert Handgretinger, University of Tübingen, Germany.