Abstract: ObjectiveTo explore the correlation of the different expression changes of Ki67 after neoadjuvant chemotherapy and chemotherapy curative effect for the different molecular classification breast cancers. MethodsOne hundred and sixty cases with breast surgery in Zhengxing Hospital of Zhangzhou of Fujian Province from March 2008 to March 2010 were selected using simple random sampling method (40 cases of Luminal A, 61 cases of Luminal B, 21 cases of HER2 over expression type, 38 cases of three negative breast cancer). All included patients were treated with neoadjuvant chemotherapy, every 21 days for a cycle, a total of 4 cycles. The expressions of Ki67 before and after neoadjuvant chemotherapy were detected, and the correlations of Ki67 expression changes and chemotherapy curative effect for the different molecular classification breast cancers were analyzed. ResultsAfter neoadjuvant chemotherapy, the pathological complete response rates of the four types of breast cancer were 12.5%, 14.8%, 19.0%, 28.9%, with statistical significant (χ2=8.992, P=0.030). For Luminal A type and triple negative breast cancer, there were statistical significant differences for 5year disease free survival rates of patients with Ki67 decreased and those patients with Ki67 increased or to usual (81.3% vs. 61.3%, χ2=9.021, P=0.031; 54.3% vs. 41.2%, χ2=7.583, P=0.043). Multifactor analysis revealed that neoadjuvant chemotherapy curative effect (RR=3.12, 95%CI: 1.373.54, χ2=12.183, P=0.001) and clinical stage (RR=2.16, 95%CI: 1.222.79, χ2=8.057, P=0.005) were independent factors for patients with Luminal A type breast cancer. Neoadjuvant chemotherapy curative effect (RR=2.57, 95%CI: 1.873.15, χ2=4.832, P=0.027), clinical stage (RR=2.70, 95%CI: 1.723.79, χ2=5.218, P=0.015) and expression change of Ki67 (RR=2.15, 95%CI: 2.132.38, χ2=4.276, P=0.044) were independent factors for patients with triple negative breast cancer. ConclusionThe expression change of Ki67 after neoadjuvant chemotherapy is the independent factor of the disease free survival rates for patients with triple negative breast cancer. Ki67 has some reference value for the prognosis of triple negative breast cancer.

Key words: Neoadjuvant therapy, Ki-67 antigen, Breast neoplasms