Abstract: Objective To explore the clinical value of cytoplasm thymidine kinase1 (TK1) in diagnosis of lung cancer.Methods Fifty in-patients with lung cancer were collected from Jan 2016 to Jun 2016, including 23 cases of adenocarcinoma, 27 cases of squamous cell carcinoma, 50 cases of benign lung disorders, and 50 cases of healthy individuals as control. Serum TK1, Cy211, NSE, CEA, and other lung tumor markers as well, were examined.Results The levels of TK1, Cy211, NSE, and CEA were remarkably higher in the lung cancer patients than in those of benign lung disorders, with the sensitivity rates of 66%, 58%, 30% and 23%,and specificity rates of 82%, 86%, 93% and 89%. No difference was noted among the cancer patients who presented different pathological types. The cancer patients showed a high level of tumor markers associated with lung cancer of pre- and post-treatments.Conclusion TK1 is sensitive an promising for screening and early diagnosis of lung cancer when compared with the other markers such as Cy211, NSE, and CEA.

Key words: Cytoplasm thymidine kinase （ TK1 ）, Lung cancer, Tumor marker