Ki-67 status in patients with primary breast cancer and its relationship with other prognostic factors

Abstract

Introduction: Breast cancer (BC) is the most common cancer in women and is the second most common cause of fatality in patients with cancer in the world. Cell proliferation plays an important role in the clinical behavior of invasive BC. We aimed to assess the status of Ki-67 in patients with primary breast cancer and evaluate the association of this tumor marker with other clinico-pathologic and prognostic factors. Methods: The current study recruited 220 patients with primary BC admitted to the oncology clinic of the Tabriz University of Medical Sciences. We evaluated Ki-67 IHC slides and reported the Ki-67 status and its relationship with other prognostic factors in breast cancer patients. Among 220 patients, 63.3% developed grade 2 tumors, and 63.8% were younger than 50-year-olds. 117 cases (53%) were Ki-67 positive with more than 1% tumor nuclei stained, and 53 cases (24%) had tumors with more than 15% of Ki-67 expression. Results: There was no correlation between Ki-67 and patient's age (Spearman rho = 0.375, tau Kendall = 0.374), tumor size (Spearman rho = 0.558, tau Kendall = 0.548) and grade (Spearman rho = 0.570, tau Kendall = 0.568), however, there was a marginally significant relationship between lymph node status and Ki-67 expression (Spearman rho = 0.077, tau Kendall = 0.079). Based on the Mann -Whitney test, there was a significant correlation between the expression of estrogen receptor (ER) and progesterone receptor (PR) with Ki-67. Conclusion: A reliable estimation of different prognostic factors in BC patients is required for the selection of an optimal therapeutic strategy. The attention has been focused on the markers of tumor biology.