Prognostic Significance of Reduction in Ki67 Index After Neoadjuvant Chemotherapy in Patients With Breast Cancer in Kerman Between 2009 And 2014

Breast cancer is the most common malignancy among women. The Neoadjuvant chemotherapy is the treatment of choice for non-operable tumors. The Ki67 is a proliferation marker that can be used to predict the therapeutic response to chemotherapy and the patient's prognosis.
This retrospective study was carried out on 55 consecutive patients with breast cancer referred to a Training Tertiary Healthcare Center in Kerman, Iran since 2009 to 2014. After diagnostic approval, the tissue samples of patients were examined for estrogen and progesterone receptors, ki67 and HER2-neu markers by using immunohistochemical staining. Then the patients were treated with 6 cycles of Neoadjuvant chemotherapy regimens by Doxorubicin and Taxans or 4 chemotherapy cycles, containing Anthracycline and Cyclophosphamide and 4 cycles of Paclitaxel. After mastectomy, their samples were reexamined for ki67 again and classified into three groups (low: ki67 30%).
Before chemotherapy, 54.5% of the patients had high expression of Ki67. But after chemotherapy, 52.7 of the patients had complete therapeutic response showing that the Ki67 level was reduced significantly (P=0.003).
Before and after Neoadjuvant chemotherapy, Ki67 measurements may be used as a predictive marker of therapeutic response.