@entity652 with early XXXX progression: a clinicopathologic and molecular study.

@entity3079 @entity1127 @entity984 @entity5 @entity189 @entity876 @entity3546 @entity8554 @entity817 @entity1893 @entity652 @entity10160
@entity652 ( @entity652 ), also referred to as @entity1127 , has been proposed as a precursor lesion to microsatellite unstable @entity189 . However, the mechanism of stepwise progression from @entity652 to early @entity189 has been unclear. The purpose of this study was to elucidate the histologic characteristics and possible role of @entity876 , @entity3546 , @entity817 , @entity984 , and @entity10160 in the development and progression of @entity652 . We analyzed 12 cases of @entity652 with @entity5 progression (SSAN), including 7 cases of intraepithelial @entity1893 ( @entity1893 ) and 5 cases of @entity189 , and compared them with 53 SSAs and 66 @entity1127 ( @entity1127 ) by immunohistochemistry and gene mutation analysis. Histologically, 75% (9 of 12) of SSANs showed tubular or tubulovillous growth patterns rather than serrated ones in the @entity189 component. All 5 SSANs with @entity189 lost their serrated structure and developed increased extracellular mucin in their @entity189 component, a consistent feature of @entity3079 . Nuclear accumulations of @entity3546 and @entity876 were observed in 50% (6 of 12) and 41.7% (5 of 12) of SSANs, respectively, and were exclusively present in @entity1893 / @entity189 areas. By contrast, neither nuclear @entity3546 nor @entity876 expressions were seen in @entity1127 or SSAs (P<0.0001). @entity817 mutations ( @entity8554 ) were observed in 45.8% (11 of 24) of @entity1127 , 60.9% (14 of 23) of SSAs, and 63.6% (7 of 11) of SSANs, and were equally found in both @entity652 and @entity189 / @entity1893 areas of the individual SSANs. @entity984 exon 1 mutations were uncommon in all 3 groups (4.2%, 4.4%, and 0%, respectively). No mutations of @entity10160 exon 9 or exon 20 were found in any cases that were examined. These findings suggest that @entity817 mutations may be associated with the pathogenesis of @entity652 , but progression to @entity1893 or early @entity189 may be associated with other factors, such as alterations of @entity876 and @entity3546 . In addition, our histologic observations suggest a possible close association between SSAN and @entity3079 .
