Department of Pathology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India; Department of Pathology, Homi Bhabha Cancer Hospital, Punjab, India.
Department of Pathology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India.
Clin Breast Cancer. 2020 Oct;20(5):382-389. doi: 10.1016/j.clbc.2020.03.012. Epub 2020 Apr 6.
Therapeutic decisions in breast carcinoma are being made on the basis of tumor cell proliferation using exorbitant genomic tests. The 2013 St Gallen meeting advocated surrogate definitions for classifying tumors into luminal subtypes on the basis of immunohistochemical (IHC) markers. We studied the classification of estrogen receptor (ER)-positive tumors using these definitions as well as different methods for Ki-67 labeling index (LI) estimation.
A total of 541 ER invasive breast carcinoma cases from January 2012 to December 2012 were evaluated for Ki-67 LI by the average and hot spot methods. The IHC results of ER, PR, and human epidermal growth factor receptor 2 (HER2) were noted. HER2 IHC equivocal (2+) samples were subjected to HER2 fluorescence in-situ hybridization testing. Luminal subgroups created on the basis of the 2013 St Gallen meeting guidelines were correlated with clinicopathologic variables and disease-free survival.
The distribution of luminal subtypes was as follows: luminal A-like, 13.3%; luminal B-like (HER2), 57.9%; and luminal B-like (HER2), 28.8%. Approximately 6% of cases were recategorized into different subgroups when the average method was used instead of the hot spot method for Ki-67 LI assessment. Younger patients (≤ 50 years), grade 3 tumors, positive axillary nodes, recurrence, and distant metastasis had a positive statistical correlation with luminal B-like (HER2) subtype. Patients with luminal B-like (HER2) tumors had a shorter disease-free survival compared to patients with luminal A-like tumors.
Ki-67 LI, irrespective of the method of assessment, along with PR, can be efficiently used to divide ER tumors into prognostic subgroups in Indian patients.
目前在乳腺癌的治疗决策中，基于肿瘤细胞增殖的情况使用昂贵的基因组检测来进行判断。2013 年圣加仑会议倡导使用免疫组织化学（IHC）标志物对肿瘤进行分类，将其分为腔面亚型，并提出替代定义。我们研究了使用这些定义以及不同 Ki-67 标记指数（LI）评估方法对雌激素受体（ER）阳性肿瘤进行分类的情况。
共评估了 2012 年 1 月至 12 月期间的 541 例 ER 浸润性乳腺癌病例，采用平均法和热点法进行 Ki-67 LI 检测。记录 ER、PR 和人表皮生长因子受体 2（HER2）的 IHC 结果。HER2 IHC 结果不确定（2+）的样本需进一步进行 HER2 荧光原位杂交检测。根据 2013 年圣加仑会议指南创建的腔面亚组与临床病理变量和无病生存相关。
腔面亚型的分布如下：腔面 A 样型占 13.3%；腔面 B 样型（HER2+）占 57.9%；腔面 B 样型（HER2-）占 28.8%。当使用平均法而不是热点法评估 Ki-67 LI 时，约有 6%的病例被重新分类到不同的亚组。年轻患者（≤ 50 岁）、3 级肿瘤、阳性腋窝淋巴结、复发和远处转移与腔面 B 样型（HER2+）亚型具有统计学相关性。与腔面 A 样型肿瘤患者相比，腔面 B 样型（HER2+）肿瘤患者的无病生存期更短。
无论评估方法如何，Ki-67 LI 与 PR 一起可有效地将 ER 肿瘤分为印度患者的预后亚组。
