Endocrine Abstracts

Differentiated thyroid cancer (DTC) is the most common malignant neoplasm arising from the thyroid parenchymal cells. DTC incidence is steadily increasing worldwide and there are approximately 1700 new cases/per year in Poland. The biopsy with subsequent thyroid resection plays a central role in the diagnosis and treatment of this malignancy. After surgery, radioactive iodine (RAI) treatment is recommended to eradicate potential residual disease and improve prognosis. Due to the fact that RAI application is associated with oxidative stress formation, this treatment may exert an important impact on homeostasis. From the other hand, it was proved that protein 53 (p53), nuclear factor kappa B (NF-kB), forkhead box protein 01 (FOXO) and sirtuin 1 (SIRT1) play a crucial role in oxidative stress as well as cancer progression. Therefore, the determination of their role may be useful in DTC clinical management. In our study, we evaluated the total oxidative status (TOS), total antioxidant capacity (TAC), and p53, NF-kB, FOXO, SIRT1 concentrations to assess diagnostic usefulness of these parameters as indication markers for RAI therapy. For the purpose of this study 60 patients diagnosed with different stages of DTC after total thyroidectomy with an indication to RAI therapy and 20 pT1a DTC patients after total thyroidectomy without any recommendation to RAI therapy were enrolled as study and control groups, respectively. Serum TOS status and SIRT1 concentration were significantly higher (both P<0.001), when TAC status and p53, NK-kB, FOXO concentrations were significantly lover (all P<0.05) in the study group compared to the control group. All the parameters were tested for their diagnostic utility as indicators for RAI treatment. The diagnostic usefulness as RAI indication markers was demonstrated for TAC (AUC=0.99), FOXO (AUC=0.78), TOC (AUC=0.76), SIRT1 (AUC=0.74), p53 (AUC=0.71) and NK-kB (AUC=0.68). Furthermore, our study revealed increased oxidative stress and decreased antioxidant capacity in DTC patients qualified for RAI treatment. This may indicate a worse prognosis and advanced neoplastic process.