Department of Pathology, The Methodist Hospital, Weill Medical College of Cornell University, Houston, TX 77030, USA.
Breast Cancer Res. 2009;11(3):R28. doi: 10.1186/bcr2258. Epub 2009 May 14.
Male breast cancer accounts for around 1% of all breast cancer cases but the incidence has risen in recent years. This study aimed to classify the molecular subtypes of male breast cancers based on the expression profile of immunomarkers and to evaluate their association with clinicopathological features and expression patterns of epidermal growth factor receptor (EGFR) and nuclear factor kappaB (NF-kappaB).
A total of 42 cases of male breast carcinoma were examined retrospectively using immunostains for estrogen receptor (ER), progesterone receptor (PR), cytokeratin 5/6 (CK5/6), EGFR, and NF-kappaB. Human epidermal growth factor receptor 2 (HER2) expression was evaluated by immunostaining and confirmed by fluorescent in situ hybridization (FISH).
The luminal A subtype was the most common subtype in male breast cancer (83%, 35/42), which was followed by the luminal B subtype (17%, 7/42). Basal-like and HER2+/ER- subtypes were not identified in this group. All carcinomas expressed ER and 67% of them were PR+. High nuclear grades were more common in the luminal B subtype (71%, 5/7) than in the luminal A subtype (34%, 12/35). The luminal B subtype carcinomas expressed EGFR (42%, 3/7) and NF-kappaB (57%, 4/7) more frequently than the luminal A subtype did (17%, 6/35 and 37%, 13/35, respectively).
In our study group, luminal A and B subtypes were the major subtypes of male breast carcinoma. The immunophenotypical features of male breast cancer differ from those of its female counterpart. Luminal B subtype tended to have high nuclear grade and more frequent expression of EGFR and NF-kappaB.
男性乳腺癌约占所有乳腺癌病例的 1%，但近年来其发病率有所上升。本研究旨在根据免疫标志物的表达谱对男性乳腺癌进行分子亚型分类，并评估其与临床病理特征以及表皮生长因子受体 (EGFR) 和核因子 kappaB (NF-kappaB) 的表达模式的关系。
回顾性分析 42 例男性乳腺癌病例，采用免疫组化法检测雌激素受体 (ER)、孕激素受体 (PR)、细胞角蛋白 5/6 (CK5/6)、EGFR 和 NF-kappaB。HER2 表达通过免疫组化评估，并通过荧光原位杂交 (FISH) 确认。
男性乳腺癌中最常见的亚型是 luminal A 型（83%，35/42），其次是 luminal B 型（17%，7/42）。在该组中未发现基底样和 HER2+/ER- 亚型。所有的癌均表达 ER，其中 67%的病例表达 PR+。在 luminal B 型中，高核级更为常见（71%，5/7），而在 luminal A 型中则较少见（34%，12/35）。与 luminal A 型相比，luminal B 型的癌更常表达 EGFR（42%，3/7）和 NF-kappaB（57%，4/7）（分别为 17%，6/35 和 37%，13/35）。
在我们的研究组中，luminal A 和 B 亚型是男性乳腺癌的主要亚型。男性乳腺癌的免疫表型特征与其女性 counterparts 不同。luminal B 型倾向于具有高核级，并且更频繁地表达 EGFR 和 NF-kappaB。
