RESUMO

Ewing sarcoma is the third most common sarcoma in children and young adults. Its characteristic chromosomal rearrangement results in a chimerical EWSR1-ETS transcription factor. Secondary genetic alterations are very common. Membranous expression of CD99 is seen in almost all tumors. We report 2 unusual cytogenetic findings in a pediatric Ewing sarcoma, an insertion of the MIC2 gene encoding CD99 from Xp to 10p and a submicroscopic deletion of the well-known tumor supressor gene KLF6. The latter has not been described previously in pediatric neoplasms. Molecular pathways in tumorigenesis and genetic complexity in cancer are discussed.

Assuntos

Neoplasias Ósseas/genética , Deleção de Genes , Fatores de Transcrição Kruppel-Like/genética , Proteínas Proto-Oncogênicas/genética , Sarcoma de Ewing/genética , Antígeno 12E7 , Antígenos CD/genética , Moléculas de Adesão Celular/genética , Criança , Humanos , Hibridização in Situ Fluorescente , Fator 6 Semelhante a Kruppel , Masculino