The Expression And Significance About Ki-67 In Different Subtypes Breast Cancer Pre-and Post-neoadjuvant Chemotherapy

ObjectiveResearch the expression of Ki-67 in different subtype breast cancer and its change after treated with neo-adjuvant chemotherapy, and then find the relationship between them. Explore the value of Ki-67 in prediction of response to neo-adjuvant chemotherapy in different breast cancer molecular subtypes. Provide certain theory and clinical evidence for individual neo-adjuvant chemotherapy of breast cancer.MethodsSelect 229 breast cancer patients from stage II to III, Punctured the breast tumor, biopsy diagnosised, observed and evaluated the expression of ER, PgR, HER2 and Ki-67 by immunohistochemistry. According to immunohistochemical stains results, they can be divided into four subtypes, respectively:Luminal-like A, luminal-like B, HER2 over-expression and triple-negative. All patients were accepted 2-4 cycles neo-adjuvant chemotherapy, then surgical treatment. Observed the expression change of ER, PgR, HER2 and Ki-67 after neo-adjuvant chemotherapy. Neo-adjuvant chemotherapy plans:anthracycline-based combinational solutions, taxane-based combinational solutions or anthracycline combined with taxane. Specific use:the dosage of all neo-adjuvant chemotherapy drugs refer to NCCN standards, THP-ADM 50～60mg/m2, Epirubicin 80～100mg/m2, Docetaxel 75 100mg/m2, Paclitaxel Liposome 135～175mg/m2,21 days for a cycle. Curative effect estimated according to RECIST 1.1. Satistics analysis data used SPSS 17.0 system, P<0.05 was considered as statistical significance.ResultsThe expression of Ki-67 in different breast cancer subtypes was significantly differential (P<0.05), positive expression rate of luminal-like A subtype breast cancer was minimum,60.6% (66 cases/109 cases), triple negative breast cancer was 75%(42 cases/56 cases), luminal-like B subtype and HER2 over-expression breast cancer were 88.6%(31 cases/ 35 cases) and 86.2%(25 cases/29 cases), higher. After neo-adjuvant chemotherapy pCR of different breast cancer molecular subtypes were significant difference (P<0.05), HER2 over-expression subtype was 20.7%, triple negative was 14.3%, luminal B subtype was 5.7%, luminal A subtype 0.9%was (0.9%). After neo-adjuvant chemotherapy the change of Ki-67 in different subtypes breast cancer were difference (P<0.005). The chemotherapy efficacy of Ki-67 positive expression ones were more obvious than negative ones, and RR was correlated with Ki-67 significantly dropped (P<0.05). Conclusion(1)In different subtype breast cancer, the expression of Ki-67 were difference, form high to low in turn:luminal B,HER2 over expression triple negative,luminal A.(2) After neo-adjuvant chemotherapy, the change of Ki-67 in different subtype breast cancer was correlated with molecular subtypes.(3)After neo-adjuvant chemotherapy, RR of Ki-67 obviously decreased ones were higher than others. Ki-67 can be used as one of the molecular biological indexes observing the curative effect neo-adjuvant chemotherapy.