Intratumoral heterogeneity of ERBB2 amplification and HER2 expression in micropapillary urothelial carcinoma.

摘要: Micropapillary urothelial carcinoma (MPUC) is a rare but an aggressive variant of carcinoma. MPUC has been shown to commonly exhibit ERBB2 amplification and HER2 protein overexpression, the frequency distribution these findings within micropapillary (MP) not otherwise specified (NOS) components tumors with mixed histology have addressed. Therefore, we evaluated expression in 43 cases by fluorescence situ hybridization (FISH) immunohistochemistry (IHC). Of 35 containing both MP NOS components, was present 12 (34.3%), only component 11 (31.4%), exclusively 4 (11.4%). overexpression significantly more compared same tumor (68.6% versus 34.3%, P = .012). Overall, there moderately positive correlation between (ρ 0.59, < .001) 0.70, components. All MP/NOS areas IHC score 3+ none 0 were associated amplification. We conclude that are preferentially identified tumor. Our identify presence intratumoral heterogeneity provide grounds for further investigation into mechanisms underlying development MPUC.