Reyes Carolina, Jorda Merce, Gomez-Fernández Carmen
Department of Pathology, University of Miami Miller School of Medicine, Jackson Memorial Hospital and Sylvester Cancer Center, Miami, FL, USA.
Appl Immunohistochem Mol Morphol. 2013 Jul;21(4):283-6. doi: 10.1097/PAI.0b013e31826a277e.
Salivary gland-like tumors represent approximately 2% of primary breast carcinomas. These special histologic subtypes are characteristically negative for ER, PR, and HER2 (triple negative), and include adenoid cystic carcinoma, mucoepidermoid carcinoma, acinic cell carcinoma, and polymorphous low-grade adenocarcinoma. Approximately 75% of triple-negative breast carcinomas belong to the basal-like subtype by gene expression profiling. Immunohistochemical panels that include basal-like markers such as EGFR, CK5/6, p-cadherin, p63, and c-kit provide useful surrogates to gene expression arrays for classification of triple-negative breast cancers into the basal-like subtype. The purpose of this study was to explore the expression of these markers in salivary gland-like tumors of the breast.
Excisional specimens from 10 untreated invasive triple-negative mammary carcinomas with salivary gland-like morphologies were evaluated for the immunohistochemical expression of EGFR, CK5/6, p-cadherin, p63, and c-kit using formalin-fixed, paraffin-embedded tissue and the L-SAB detection method.
On the basis of morphology, 5 carcinomas were classified as adenoid cystic, 3 as mucoepidermoid, and 2 as polymorphous low grade. All of the adenoid cystic carcinomas, mucoepidermoid carcinomas, and polymorphous low-grade adenocarcinomas showed strong and diffuse expression of CK5/6, p-cadherin, and p63. EGFR was expressed weakly in adenoid cystic carcinomas and polymorphous low grade, whereas mucoepidermoid carcinomas had a stronger expression. C-kit was expressed in adenoid cystic carcinomas and low-grade polymorphous, but only weakly positive in mucoepidermoid carcinomas.
Adenoid cystic, mucoepidermoid, and polymorphous low-grade carcinomas of the breast express immunohistochemical markers that characterize the intrinsic basal-like subtype of breast cancer.
涎腺样肿瘤约占原发性乳腺癌的2%。这些特殊的组织学亚型典型地雌激素受体（ER）、孕激素受体（PR）和人表皮生长因子受体2（HER2）均为阴性（三阴性），包括腺样囊性癌、黏液表皮样癌、腺泡细胞癌和多形性低度腺癌。通过基因表达谱分析，约75%的三阴性乳腺癌属于基底样亚型。包括表皮生长因子受体（EGFR）、细胞角蛋白5/6（CK5/6）、p-钙黏蛋白、p63和干细胞生长因子受体（c-kit）等基底样标志物的免疫组化检测有助于替代基因表达阵列，将三阴性乳腺癌分类为基底样亚型。本研究的目的是探讨这些标志物在乳腺涎腺样肿瘤中的表达情况。
采用福尔马林固定、石蜡包埋组织及L-SAB检测方法，对10例未经治疗的具有涎腺样形态的浸润性三阴性乳腺癌切除标本进行EGFR、CK5/6、p-钙黏蛋白、p63和c-kit的免疫组化表达评估。
根据形态学，5例癌被分类为腺样囊性癌，3例为黏液表皮样癌，2例为多形性低度癌。所有腺样囊性癌、黏液表皮样癌和多形性低度腺癌均显示CK5/6、p-钙黏蛋白和p63呈强弥漫性表达。EGFR在腺样囊性癌和多形性低度癌中弱表达，而黏液表皮样癌表达较强。c-kit在腺样囊性癌和低度多形性癌中表达，而在黏液表皮样癌中仅弱阳性。
乳腺腺样囊性癌、黏液表皮样癌和多形性低度癌表达免疫组化标志物，这些标志物是乳腺癌固有基底样亚型的特征。
