Expression and clinical significance of thymidine kinase 1 and Ki67 in osteosarcoma

FU Yu-cheng; ZHENG Chuan-xi; ZHANG Shi-quan; GUAN Hong; LI Wei; TAN Ji-feng

doi:10.3969/j.issn.2095-252X.2017.02.011

Abstract：Objective To test the level of thymidine kinase 1 ( TK1 ) and Ki67 in the osteosarcomas, to compare the difference in the clinical features and prognosis. Methods The expressions of TK1 and Ki67 in 50 cases of osteosarcoma and 20 cases of osteochondroma tissues were studied by immunohistochemical staining. Results The positive rate of TK1 and Ki67 in osteosarcoma group was 84% ( 42 / 50 ) and 54% ( 27 / 50 ), in osteochondroma group was 10% ( 2 / 20 ) and 15% ( 3 / 20 ), respectively. There was a significant difference in the expression of TK1 and Ki67 between the 2 groups. In osteosarcoma group, the positive rate of TK1 was significantly higher than Ki67. Both markers had a significant correlation in Enneking stage and the local recurrence. But there were no significant differences in gender, age, tumor size, and pathological type . Besides, the expression of TK1 was significantly different in tumor cell necrosis rate and lung metastasis. The median survival time of TK1 high expression patients ( positive rate > 25% ) was significantly shorter than low expression patients. Univariate analysis showed that local recurrence, Enneking stage, lung metastasis and TK1 expression were the factors influencing the prognosis of osteosarcoma patients. Multivariate analysis showed that the expression level of lung metastasis ( P = 0.012 ) and TK1 ( P = 0.002 ) were independent factors influencing the prognosis of osteosarcoma. Conclusions The expression of Ki67 and TK1 shows significant differences in benign and malignant tumors. TK1 is more sensitive than Ki67 in osteosarcoma. TK1 is more related to the clinical and pathology features in osteosarcoma. The expression of TK1 could be a predictor of the prognosis of osteosarcoma.