The Levels of Ki-67 Positive are Positively Associated with Lymph Node Metastasis in Invasive Ductal Breast Cancer

Breast cancer is the most common cancer in women worldwide. In this study, we evaluate the potential risk factors for lymph node metastasis in invasive breast cancer patients with axillary dissection. 147 patients were included into this prospective study. The prognostic biomarkers including Ki-67, human epidermal growth factor receptor 2 (HER-2), hormone receptor status, p53, and lymph node involvement were determined by immunohistochemistry. The association between lymph node metastasis and these biomarkers was analyzed. Lymph node metastasis was found in 62 patients out of 147 patients. The high levels of Ki-67 positive (greater than 20 %) were positively correlated with a higher incidence of lymph node metastasis, including the numbers of lymph nodes that contain tumor cells and the lymph node metastatic rate. The high rate of positive lymphovascular invasion (LVI) is associated with lymph node metastasis. However, the levels of Ki-67 positive were not correlated with the positive rate of LVI. There was also no association between lymph node metastasis and other prognostic biomarkers, such as HER-2, estrogen receptor, progesterone receptor, and p53. In addition, apart from p53, the levels of Ki-67 positive were correlated with other prognostic biomarkers. Our data suggest that Ki-67 positivity has value as a prognostic and predictive biomarker in breast cancer and may be a valuable proliferation marker in routine diagnosis of breast cancer.