My clinical research has focused on the development of innovative therapies for pediatric solid tumors, in particular retinoblastoma, sarcomas, and rare cancers. In the field of retinoblastoma, I lead a multidisciplinary team that integrates clinical and research initiatives focused on the development of a state of the art treatment center and advancement of science. In the RET5 protocol, I developed a comprehensive preclinical and clinical research program for the development of new agents and identification of molecular targets. Because retinoblastoma occurs at such early age, when the visual pathways are still developing, we are investigating changes in visual pathways occurring in those children. The information provided by this research will be very relevant to our understanding of brain development during infancy. In adrenocortical tumors, our group at St Jude identified a novel germline TP53 mutation in Brazilian children that results in a novel model of tumorigenesis. I continued to build on those findings and developed an international study through the Childrenâ€™s Oncology Group (ARAR0332) that investigates biology and treatment of this malignancy. As part of those studies, we have identified a unique pattern of gene expression that will help characterize those tumors with malignant behavior. I have also developed a national research study for pediatric nasopharyngeal carcinoma (ARAR0331) that incorporates new concepts in the treatment of this malignancy and explores the role of EBV in its pathogenesis. Additional research initiatives in pediatric malignancies include my extensive work on the Ewing sarcoma, osteosarcoma and soft tissue sarcomas. My research in histiocytic disorders has centered in the use of nucleoside analogues in the treatment of Langerhans cell histiocytosis. My work on those fields has led to me assuming leadership roles in cooperative groups. I am the Chair of the Retinoblastoma and Rare Tumor Committee at the Childrenâ€™s Oncology Group, and the Secretary of the Board and PI of the LCH-IV study of the Histiocyte Society.