摘要:

The histopathologic diagnosis of Ewing's sarcoma has always been difficult, and its histogenesis has never been elucidated. Developments in the molecular pathology of the sarcoma and cytogenetically related tumors have not only provided considerable diagnostic assistance but also have opened new views on the classification of a formerly heterogeneous group of neoplasms. Chromosome translocations t(11;22) (q24;q12) and t(21;22) (q22;1q12) and their chimeric fusion oncoproteins are now the hallmarks of the Ewing's sarcoma/peripheral primitive neuroectodermal tumor family. In this review, we present the molecular basis of this family and its interrelationships, summarize advances in diagnosis, and relate these to prognosis. Finally, histogenetic (developmental, embryologic, and microenvironmental) theories are discussed with the conclusion that the histogenesis of this subset of sarcomas does not necessarily follow a genetic commonality.

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The diagnostic term atypical squamous cells of undetermined significance (ASCUS) was introduced with the Bethesda System to describe cervical/vaginal smears displaying cytologic changes of uncertain clinical significance. The diagnosis does not identify a specific entity, but reflects one of the inherent limitations of the pap screening procedure. Cervical/vaginal cytology cannot always distinguish reactive from dysplastic changes. Specific cytomorphologic criteria, guidelines for the management of ASCUS diagnoses, the risk of underlying dysplasia, and the natural history of ASCUS have been published. Recently, stratification of ASCUS cases by morphologic features and testing for human papillomavirus have been studied. However, the diagnosis itself remains poorly understood and controversial. The controversy is caused in part by the lack of consistency and reproducibility of ASCUS diagnoses, but it also is related to the struggle to define a modern approach for screening and managing preneoplastic lesions of the uterine cervix.

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1997

数据来源: OVID