Expressions And Clinical Significance Of TK1 And Ki-67 In Triple Negative Breast Cancer

Objective: To investigate the expressions and clinical significance of Thymidine Kinase 1(TK1) and nuclear-associated antigen Ki-67(Ki-67) in triple negative breast cancer(TNBC) and their prognosis..Methods: There were 120 cases of breast cancer patients collected randomly who was performed breast conservation treatment or modified mastectomy in the Second Affiliated Hospital of Qingdao University Medical College from June 2009 to December2010, including 60 patients with TNBC and 60 patients with non-triple negative breast cancer(NTNBC). All the patients were women, whose average age is 51 years(21~81years). The expression of TK1 and Ki-67 in two kinds of breast tissues were detected by immunohistochemistry(IHC) technique. Pearson’s chi-square(χ2) test were used to analyze the relationship between the expression status and clinicopathologic features such as age, tumor size,.menopausal status, histologic classification and lymph node metastasis. The 5 years-DFS rate between TK1, Ki-67 positive expression and TK1,Ki-67 negative expression in TNBC tissues was analyzed by Kaplan-Meier method(log-rank test).Results: The rates of TK1 positive expression in TNBC tissues and non-TNBC tissues were 83.33% and 51.67%, respectively, with a significant statistical difference(χ2=13.713, P=0.000). The rates of Ki-67 positive expression in TNBC tissues and non-TNBC tissues were 68.33% and 31.67%, respectively, with a significant statistical difference(χ2=16.133, P=0.000). The expressions of TK1 were closely related to histological staging(χ2=6.125, P=0.013), but it was not related to onset age(χ2=0.809,P=0.369), menopausal status(χ2=1.615, P=0.204), tumor size(χ2=0.054, P=0.816) and lymph node metastasis(χ2=0.672, P=0.412) in TNBC tissues. The expressions of Ki-67 were closely related to histological staging(χ2=13.145, P=0.000) and lymph node metastasis(χ2=6.182, P=0.013), but it was not related to menopausal stutas(χ2=1.018,P=0.313), onset age(χ2=2.377, P=0.123) and tumor size(χ2=2.401, P=0.121) in TNBC tissues. Spearman correlation analysis showed that the expression of TK1 was closely correlated with Ki-67 expression(χ2=5.143; r=0.369, P=0.023). The results of survivalanalysis showed that the disease-free survival rates of 5-year were 28.20% and 66.70% in the TK1 positive expression group and TK1 negative expression group, and the disease-free survival rates of 5-year were 24.30% and 64.30% in the Ki-67 positive group and Ki-67 negative group, with significant statistical differences(χ2=4.194, P=0.041;χ2=4.540, P=0.033).Conclusion: The expressions of TK1 and Ki-67 in TNBC tissues are positively related with histological staging and disease-free survival, which are expected to become prognostic clinical indicators.