Women's College Research Institute, University of Toronto, Toronto, Ontario, Canada.
Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
Clin Genet. 2021 May;99(5):613-637. doi: 10.1111/cge.13900. Epub 2020 Dec 28.
Breast cancer is a heterogeneous disease manifesting diversity at the molecular, histological and clinical level. The development of breast cancer classification was centered on informing clinical decisions. The current approach to the classification of breast cancer, which categorizes this disease into clinical subtypes based on the detection of estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and proliferation marker Ki67, is not ideal. This is manifested as a heterogeneity of therapeutic responses and outcomes within the clinical subtypes. The newer classification model, based on gene expression profiling (intrinsic subtyping) informs about transcriptional responses downstream from IHC single markers, revealing deeper appreciation for the disease heterogeneity and capturing tumor biology in a more comprehensive way than an expression of a single protein or gene alone. While accumulating evidences suggest that intrinsic subtypes provide clinically relevant information beyond clinical surrogates, it is imperative to establish whether the current conventional immunohistochemistry-based clinical subtyping approach could be improved by gene expression profiling and if this approach has a potential to translate into clinical practice.
乳腺癌是一种异质性疾病，在分子、组织学和临床水平上表现出多样性。乳腺癌分类的发展以指导临床决策为中心。目前，乳腺癌的分类方法是基于雌激素受体、孕激素受体、人表皮生长因子受体 2 和增殖标志物 Ki67 的检测，将这种疾病分为临床亚型，但并不理想。这表现为临床亚型内治疗反应和结果的异质性。基于基因表达谱（内在分型）的新型分类模型可以了解免疫组织化学单标记物下游的转录反应，更全面地了解疾病的异质性，并比单一蛋白或基因的表达更全面地捕获肿瘤生物学。虽然越来越多的证据表明内在亚型提供了超越临床替代物的临床相关信息，但至关重要的是要确定是否可以通过基因表达谱来改进当前基于常规免疫组织化学的临床亚型分类方法，以及这种方法是否有可能转化为临床实践。
