CD10 Immunohistochemical Expression in Apocrine Lesions of the Breast

Abstract

Objective: In the breast, CD10 is expressed by myoepithelial cells (MECs), and apocrine metaplasia has also been mentioned as being positive with this marker. Apocrine lesions have been explored for the expression of CD10. Methods: The apocrine lesions studied included 11 cysts, 6 cases of apocrine adenosis, 2 of apocrine metaplasia or hyperplasia in papilloma, 13 ductal carcinomas in situ (DCIS) and invasive carcinomas (14 ductal and 4 lobular). Results: Benign apocrine lesions showed complete or partial luminal CD10 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 DCIS displayed no luminal staining, but 4 demonstrated very focal luminal positivity. The MECs around the DCIS showed a spectrum of staining from nil to strong and complete. Only 4 invasive carcinomas demonstrated luminal/membranous staining. Cytoplasmic CD10 positivity was seen focally in 4 invasive cancers and in 3 DCIS. Conclusion: CD10 positivity is luminal/membranous in most benign apocrine lesions, the staining being nonuniversal and sometimes focal. Analogous staining in apocrine malignancies seems rarer in DCIS and even rarer in invasive apocrine carcinomas, but atypical cytoplasmic positivity may also occur. CD10 is not an ideal myoepithelial marker in apocrine lesions.

Analysis of membranous Ki-67 staining in breast cancer and surrounding breast epithelium

“…Another discrepancy from the previously cited study [14] was the more commonly seen polarised luminal staining rather than complete circumferential staining of the cells. This pattern is reminiscent of the focal to diffuse CD10 membrane positivity seen in apocrine lesions [22]. An area of micropapillary differentiation in an NST carcinoma (but not in the single micropapillary carcinoma case) also demonstrated the inside-out pattern of polarised membranous staining which is typical of this histological type of cancer with the MUC1 antibody [20].…”

Apocrine Encapsulated Papillary Carcinoma of the Breast: The First Reported Case with an Infiltrative Component

“…The gross examination discovered a correlating dual lesion, which consisted of an intracystic proliferation and a tumor mass that was ill-defined and infiltrative in appearance ( Figure 1D ). Microscopically, the intracystic portion showed a thick fibrous capsule, an intraluminal dominantly papillary, partially solid proliferation, and a total absence of MEC, under H&E staining and p63, cytokeratin 5, smooth muscle actin, and CD10 IHC ( Figure 2 ) [ 13 ]. The ill-defined component represented a NST invasive carcinoma with desmoplasia.…”

Predictive role of neostromal CD10 expression in breast cancer patients treated with neoadjuvant chemotherapy

“…CD10 is a 90-110-kDa cell surface zinc-dependent metalloprotease that is normally expressed by the epithelial cells of diverse tissues, including prostate, colon, liver, stomach and apocrine breast lesions, but is also present in endometrial stroma (6)(7)(8)(9). The detection of CD10 is a useful tool in numerous pathological entities, such as acute lymphomas and non-malignant tumors of the breast (10).…”