Ki-67 expression in primary breast carcinomas and their axillary lymph node metastases: clinical implications

Abstract

Proliferative activity of tumour cells assessed by immunohistochemical Ki-67 expression is one of several prognostic indicators in breast cancer. The major objective of this study was to investigate the prognostic impact of Ki-67 proliferative activity in the axillary lymph node metastases and in the matched primary breast carcinoma from 194 patients. There was a statistically significant up-regulation of Ki-67 protein in the metastatic deposit compared to where the primary tumour was found (p = 0.001). A low Ki-67 index in both the primary and the metastatic tumours was a favorable prognostic factor. A high index in both primary and metastatic lesion and an up-regulation from a low index in the primary tumour to a high index in the metastatic deposit represented an unfavorable prognostic factor. Multivariate analysis showed that Ki-67 expression in the metastases was a superior independent prognostic factor of clinical outcomes compared to that in the primary tumours. Ki-67 expression in > or =10% of carcinoma cells in the primary tumours and > or =15% in the nodal metastases seems to be optimal cut-off levels. Ki-67 is of value as an independent prognostic factor in breast cancer.

Invasive ductal carcinoma of no special type and its corresponding lymph node metastasis: do they have the same immunophenotypic profile?

“…These results can be explained partly by Zhou's data, where luminal A and B subtypes had the highest risk of metastasis in non-sentinel lymph nodes [24]. These 7 cases are in contradiction with Park's data, which affirm significant up-regulation of Ki-67 protein in the metastatic site compared to the primary tumor [25].…”

Impact of intratumoural heterogeneity on the assessment of Ki67 expression in breast cancer

“…Immunohistochemical (IHC) detection of proliferation associated antigens have long been studied in breast as well as other cancers [1]. Ki67 is a labile non-histone nuclear protein of approximately 395 kDa, amount of which is tightly regulated during cell cycle.…”

“…Therefore, it has been used as a biomarker to assay the growth fraction of a given cell population [1,5]. Nuclear positivity of Ki67 protein is an indication of cell proliferation [6,7] and it has long been reported as a prognostic marker in breast cancer (BC) [8][9][10][11].…”

Molecular-Based Diagnostic, Prognostic and Predictive Tests in Breast Cancer

“…An additional problem with this approach is the cost and feasibility of microarray and chip gene expression technology for routine management of breast cancer. Alternatively, immunohistochemistry (IHC) is considered a practical, cost-effective and reliable technique for molecular classification and the gold standard in the routine assessment of the essential predictive molecular biomarkers; ER, PR and HER2 [11,12].…”