1. Children’s Hospital Colorado, University of Colorado, Denver, CO
2. Unidad Nacional de Oncología Pediátrica, Guatemala City, Guatemala
3. Hospital J.P. Garrahan, Buenos Aires, Argentina
4. Hospital Universitario, Tegucigalpa, Honduras
5. Hospital Herrera Llerandi, Guatemala City, Guatemala
6. Hospital Infantil Bloom, San Salvador, El Salvador
7. Hospital Infantil Manuel de Jesús Rivera–La Mascota, Managua, Nicaragua
8. Centro Nacional de Oftalmología, Managua, Nicaragua
9. Hospital Solca, Quito, Ecuador
10. University of Tennessee Health Sciences Center, Memphis, TN
11. St Jude Children’s Research Hospital, Memphis, TN