Institute of Molecular Pathology and Immunology of Porto University, Porto, Portugal.
BMC Cancer. 2011 Jul 15;11:299. doi: 10.1186/1471-2407-11-299.
A breast cancer prognostic tool should ideally be applicable to all types of invasive breast lesions. A number of studies have shown histopathological grade to be an independent prognostic factor in breast cancer, adding prognostic power to nodal stage and tumour size. The Nottingham Prognostic Index has been shown to accurately predict patient outcome in stratified groups with a follow-up period of 15 years after primary diagnosis of breast cancer. Clinically, breast tumours that lack the expression of Oestrogen Receptor, Progesterone Receptor and Human Epidermal growth factor Receptor 2 (HER2) are identified as presenting a "triple-negative" phenotype or as triple-negative breast cancers. These poor outcome tumours represent an easily recognisable prognostic group of breast cancer with aggressive behaviour that currently lack the benefit of available systemic therapy. There are conflicting results on the prevalence of lymph node metastasis at the time of diagnosis in triple-negative breast cancer patients but it is currently accepted that triple-negative breast cancer does not metastasize to axillary nodes and bones as frequently as the non-triple-negative carcinomas, favouring instead, a preferentially haematogenous spread. Hypothetically, this particular tumour dissemination pattern would impair the reliability of using Nottingham Prognostic Index as a tool for triple-negative breast cancer prognostication.
The present study tested the effectiveness of the Nottingham Prognostic Index in stratifying breast cancer patients of different subtypes with special emphasis in a triple-negative breast cancer patient subset versus non- triple-negative breast cancer.
We demonstrated that besides the fact that TNBC disseminate to axillary lymph nodes as frequently as luminal or HER2 tumours, we also showed that TNBC are larger in size compared with other subtypes and almost all grade 3. Additionally, survival curves demonstrated that these prognostic factors are equally important to stratify different survival outcomes in non-TNBC as in TNBC. We also showed that the NPI retains the ability to stratify and predict survival of TNBC patients.
The importance of this study relies on the need of prognostication improvements on TNBC, showing, at a clinical standpoint, that Nottingham Prognostic Index is as a truthful prognostic tool in TNBC.
理想情况下，乳腺癌预后工具应适用于所有类型的浸润性乳腺病变。多项研究表明，组织病理学分级是乳腺癌的独立预后因素，为淋巴结分期和肿瘤大小增加了预后能力。诺丁汉预后指数已被证明可在乳腺癌原发诊断后 15 年的分层组中准确预测患者的结局。临床上，缺乏雌激素受体、孕激素受体和人表皮生长因子受体 2（HER2）表达的乳腺肿瘤被确定为表现出“三阴性”表型或三阴性乳腺癌。这些预后不良的肿瘤代表了一种易于识别的乳腺癌预后组，具有侵袭性行为，目前缺乏现有系统治疗的获益。三阴性乳腺癌患者在诊断时发生淋巴结转移的患病率存在矛盾的结果，但目前认为三阴性乳腺癌不像非三阴性癌那样频繁转移到腋窝淋巴结和骨骼，而是更倾向于优先血行播散。从理论上讲，这种特定的肿瘤播散模式会降低诺丁汉预后指数作为三阴性乳腺癌预后预测工具的可靠性。
本研究测试了诺丁汉预后指数在分层不同亚型乳腺癌患者中的有效性，特别强调了三阴性乳腺癌患者亚组与非三阴性乳腺癌患者的对比。
我们证明，除了三阴性乳腺癌与 luminal 或 HER2 肿瘤一样频繁转移到腋窝淋巴结之外，我们还发现三阴性乳腺癌比其他亚型更大，几乎所有都是 3 级。此外，生存曲线表明，这些预后因素对于分层非三阴性乳腺癌和三阴性乳腺癌的不同生存结局同样重要。我们还表明，NPI 仍然能够分层并预测三阴性乳腺癌患者的生存。
本研究的重要性在于需要改善三阴性乳腺癌的预后，从临床角度表明，诺丁汉预后指数是三阴性乳腺癌的真实预后工具。
