Progressive @entity1141 and @entity2007 are hallmarks of XXXX skin papillomas: relevance to @entity5 .

@entity3653 @entity981 @entity2007 @entity5 @entity19 @entity1185 @entity75 @entity1359 @entity189 @entity2008 @entity6349 @entity1141
We report a systematic histopathologic study of @entity1185 at different times during promotion, correlating the results with those from cytogenetic analysis of the same @entity5 . @entity1185 were induced in SENCAR @entity19 by two-stage carcinogenesis ( @entity3653 and @entity1359 ). Individual @entity5 were randomly sampled at different times during promotion, and histopathologic and cytogenetic studies were carried out on every @entity5 . Early during promotion (10 weeks), most @entity1185 were well-differentiated @entity75 with mild or no cellular atypia. No @entity5 showed severe @entity6349 changes. By 20 weeks of promotion, a dramatic drop had occurred in the number of lesions with no @entity1141 . Most of the @entity5 presented moderate @entity1141 , and some already showed severe @entity6349 changes. At later stages (30-40 weeks), most of the @entity1185 were classified as moderately or severely @entity1185 , and several were considered to be @entity189 . This histopathologic evaluation was supported by nuclear measurements performed on @entity1185 at different time points. @entity2008 followed a similar trend. @entity1185 seem to start as diploid lesions, but between 10 and 20 weeks of promotion, @entity981 cells can be observed in almost every @entity5 . In some cases the stem line was taken over by @entity2007 clones. At 40 weeks of promotion, all @entity1185 were @entity2007 , most of them with @entity981 stem lines. A positive correlation was found between the histological and cytogenetic studies, with the most aggressive and @entity5 being the more @entity2007 . These results support the idea that most, if not all, @entity1185 are truly @entity75 in different stages of the potential progression toward @entity5 . @entity2008 might play an important role in the sequence of events leading to @entity5 .
