1. From the Departments of Pediatrics (S.L.M., S.A.G.) and Pathology and Laboratory Medicine (C.H.J., B.L.L.), Perelman School of Medicine, and Abramson Cancer Center (C.H.J., B.L.L.), University of Pennsylvania, and the Division of Oncology, Center for Childhood Cancer Research and Cancer Immunotherapy Program, Children’s Hospital of Philadelphia (S.L.M., S.A.G.) — all in Philadelphia; the Department of Pediatrics and Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical...