Abstract：
Gene expression profiling has reshaped our understanding of breast cancer by identifying four molecular subtypes: (1) luminal A, (2) luminal B, (3) human epidermal growth factor receptor 2 (HER2)-enriched, and (4) basal-like, which have critical differences in incidence, response to treatment, disease progression, survival, and imaging features. Luminal tumors are most common (60%-70%), characterized by estrogen receptor (ER) expression. Luminal A tumors have the best prognosis of all subtypes, whereas patients with luminal B tumors have significantly shorter overall and disease-free survival. Distinguishing between these tumors is important because luminal B tumors require more aggressive treatment. Both commonly present as irregular masses without associated calcifications at mammography; however, luminal B tumors more commonly demonstrate axillary involvement at diagnosis. HER2-enriched tumors are characterized by overexpression of the HER2 oncogene and low-to-absent ER expression. HER2+ disease carries a poor prognosis, but the development of anti-HER2 therapies has greatly improved outcomes for women with HER2+ breast cancer. HER2+ tumors most commonly present as spiculated masses with pleomorphic calcifications or as calcifications alone. Basal-like cancers (15% of all invasive breast cancers) predominate among \"triple negative\" cancers, which lack ER, progesterone receptor (PR), and HER2 expression. Basal-like cancers are frequently high-grade, large at diagnosis, with high rates of recurrence. Although imaging commonly reveals irregular masses with ill-defined or spiculated margins, some circumscribed basal-like tumors can be mistaken for benign lesions. Incorporating biomarker data (histologic grade, ER/PR/HER2 status, and multigene assays) into classic anatomic tumor, node, metastasis (TNM) staging can better inform clinical management of this heterogeneous disease.
摘要：
基因表达谱通过识别四种分子亚型重塑了我们对乳腺癌的理解：（1）管腔A，(2)管腔B,（3）人表皮生长因子受体2（HER2）富集，和（4）基底样，在发病率上有关键的差异，对治疗的反应，疾病进展,生存,和成像功能。管腔肿瘤是最常见的（60％-70％），以雌激素受体（ER）表达为特征。管腔A肿瘤在所有亚型中预后最好，而管腔B肿瘤患者的总体生存期和无病生存期明显较短.区分这些肿瘤很重要，因为腔B肿瘤需要更积极的治疗。两者通常表现为不规则肿块，在乳房X线照相术中没有相关的钙化；然而，管腔B肿瘤在诊断时更常表现为腋窝受累。HER2富集肿瘤的特征在于HER2癌基因的过表达和低至不存在的ER表达。HER2+疾病预后不良，但是抗HER2治疗的发展大大改善了HER2+乳腺癌女性的预后.HER2+肿瘤最常表现为伴有多形性钙化的针状肿块或仅表现为钙化。基底样癌（占所有浸润性乳腺癌的15％）在“三阴性”癌症中占主导地位，缺乏ER，孕激素受体（PR），和HER2表达。基底样癌通常是高级别，在诊断时很大，复发率高。尽管成像通常显示不规则肿块，边缘不明确或有毛刺，一些局限性的基底样肿瘤可能被误认为是良性病变。纳入生物标志物数据(组织学分级，ER/PR/HER2状态，和多基因检测）进入经典的解剖肿瘤，节点,转移（TNM）分期可以更好地指导这种异质性疾病的临床治疗。
