From the Soft Tissue Sarcoma Committee, Children's Oncology Group
Authors’ disclosures of potential conflicts of interest are found at the end of this article.
Address reprint requests Frederic G. Barr, PhD, Associate Professor of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, 36th Street and Hamilton Walk, Philadelphia, PA 19104-6082; e-mail: barrfg{at}mail.med.upenn.edu; or William H. Meyer, MD, CMRI Ben Johnson Professor of Pediatrics, University of Oklahoma Health Science Center, 940 NE 13th Street, Rm 3308, Oklahoma City, OK 73104; e-mail: william-meyer{at}ouhsc.edu
Overview: Rhabdomyosarcoma is the most common childhood soft tissue sarcoma, with about 350 new cases diagnosed each year in the United States. Rhabdomyosarcoma is a small round blue-cell tumor that demonstrates features of muscle differentiation. There are two common histologic subtypes, embryonal and alveolar, which are associated with distinct genetic changes and distinct gene expression profiles. Gene fusions involving PAX3 or PAX7 and FKHR (FOXO1A) typically occur in alveolar histology tumors. Multiple challenges confront physicians who treat children with rhabdomyosarcoma and those who conduct research on the biology and therapy of this malignancy, including the relative rarity of this tumor, its heterogeneous biology and presentation, its propensity to arise young children, which complicates therapeutic interventions, and the difficult task of translating identification of active anticancer agents into improvements in outcome. The present Children's Oncology Group studies aim to improve our understanding of the biology of rhabdomyosarcoma, decrease therapy for lower-risk patients, and identify new agents and therapy approaches for those at intermediate and high risk for treatment failure.
