%0 Journal Article %A MELISSA M. ALEGRE %A MICHAEL J. WEYANT %A DAINE T. BENNETT %A JESSICA A. YU %A MADISON K. RAMSDEN %A ATIF ELNAGGAR %A RICHARD A. ROBISON %A KIM L. O'NEILL %T Serum Detection of Thymidine Kinase 1 as a Means of Early Detection of Lung Cancer %D 2014 %J Anticancer Research %P 2145-2151 %V 34 %N 5 %X Background: Thymidine kinase 1 (TK1) is a biomarker elevated in several malignancies, including lung cancer. Up-regulation of TK1 is an early event in carcinogenesis and therefore a target for early cancer detection. We have developed a novel Enzyme Linked Immunosorbent Assay (ELISA) to detect TK1 in serum. Materials and Methods: Forty patients with pulmonary nodules and 18 healthy individuals had their serum collected prior to surgery. All samples were analyzed using a radioassay and ELISA. Results: TK1 was significantly elevated in all lung cancer samples. Patients with stage I (n=16) and stage II (n=17) disease had significantly higher TK1 levels than controls. The area under the curve was 0.792, using 4.9 nM TK1 as cut-off, for early-stage lung cancer. The sensitivity and specificity were 75.0 and 83.3, respectively. TK1 concentration was a more sensitive and accurate indicator of lung cancer than TK1 activity. Conclusion: TK1 is significantly elevated in serum from patients with stage I and stage II lung cancer as measured using the established ELISA. This novel TK1 ELISA is both sensitive and specific for the detection of early-stage and advanced lung cancer, and therefore may be an important tool in the management of this disease. %U https://ar.iiarjournals.org/content/anticanres/34/5/2145.full.pdf