Serum Concentration of Thymidine Kinase 1 (TK1) as a Tumor Marker in Soft Tissue Sarcomas

Background/Aim: The aim of this prospective study was to determine whether serum Thymidine kinase -1 (TK1) could serve as a tumor marker in soft tissue sarcomas (STS). Patients and Methods: A total of 48 patients diagnosed with localized STS were included. None had received preoperative oncological treatment. Samples were collected before and after surgery and TK1 levels measured with the AroCell TK210 ELISA. Results: Mean preoperative TK1 was 0.32 ,ug/l, range=0.11-1.47, and 18 cases (38%) had values above the reference limit (0.41 ,ug/l). Mean postoperative TK1 was 0.35 ,ug/l (0.06-0.86). In patients with preoperative values above the reference limit, TK1 decreased significantly after surgery (n=13, p=0.001). We found no association between increased preoperative TK1 and age, sex, tumor size, grade, and the presence of vascular invasion or necrosis. Conclusion: TK1 has limited use as a tumor marker in localized STS.