XXXX Immunohistochemical Expression in Apocrine Lesions of the Breast.

@entity3821 @entity5 @entity1373 @entity1185 @entity189 @entity2282 @entity4648
OBJECTIVE: In the breast, @entity2282 is expressed by myoepithelial cells (MECs), and apocrine @entity4648 has also been mentioned as being positive with this marker. Apocrine lesions have been explored for the expression of @entity2282 . METHODS: The apocrine lesions studied included 11 cysts, 6 cases of apocrine adenosis, 2 of apocrine @entity4648 or @entity1373 in @entity1185 , 13 @entity3821 ( @entity3821 ) and invasive @entity189 (14 ductal and 4 lobular). RESULTS: Benign apocrine lesions showed complete or partial luminal @entity2282 staining, although most cases included parts without staining, and 2 lesions were completely negative. The MECs were often but not always positive. Nine of the 13 cases of apocrine @entity3821 displayed no luminal staining, but 4 demonstrated very focal luminal positivity. The MECs around the @entity3821 showed a spectrum of staining from nil to strong and complete. Only 4 invasive @entity189 demonstrated luminal/membranous staining. Cytoplasmic @entity2282 positivity was seen focally in 4 invasive @entity5 and in 3 @entity3821 . CONCLUSION: @entity2282 positivity is luminal/membranous in most benign apocrine lesions, the staining being nonuniversal and sometimes focal. Analogous staining in apocrine @entity5 seems rarer in @entity3821 and even rarer in invasive @entity189 , but atypical cytoplasmic positivity may also occur. @entity2282 is not an ideal myoepithelial marker in apocrine lesions.
