[Molecular genetics of XXXX progression].

@entity2558 @entity5 @entity189 @entity876 @entity150 @entity1722
Extensive cytogenetic and molecular analyses have recently helped to gain a much better understanding of the biology of @entity150 . Early studies had suggested two different pathways of @entity150 development, one characterized by chromosome 9 losses and the other by @entity876 mutations. Subsequent studies have greatly expanded these data. Overall, there is compelling evidence for two entirely different @entity150 entities. One entity consists of genetically unstable @entity5 that have many cytogenetic alterations, including @entity876 alterations in about 50% of the cases. Other cytogenetic alterations that can be found frequently in these @entity5 are deletions of 8p, 9p, 11p, 11q, and Y as well as gains of 1q, 8q, 17q, and 20q. More than 20 chromosomal regions can undergo high level DNA amplification including 17q21 ( @entity1722 ). Phenotypically, these @entity5 are characterized by a high degree of cytological atypia. Their growth pattern can be non-invasive flat ( @entity189 in situ), non-invasive papillary (pTaG3) or invasive (papillary or solid). The other, "benign" @entity150 entity is composed of @entity5 with a low level of genetic instability, a low number of cytogenetic alterations, and absence of @entity876 mutations. Morphologically, these @entity5 are papillary non-invasive @entity5 with a low degree of cytological atypia. Progression to invasively growing @entity189 is extremely rare. CONCLUSION: Molecular studies have revealed profound genetic differences between invasive and non-invasive @entity150 . This argues against the previously used combination of pTa and @entity2558 @entity5 stages as "superficial @entity150 ". The high frequency of genetic alterations in invasive @entity189 enables a markedly improved detection of @entity150 cells in voided urine using fluorescence in situ hybridization (FISH) assays.
