RESUMO
Background: Differentiated thyroid carcinoma (DTC) has witnessed an increase in incidence and although it is considered to have a slow grow potential and a 90% 10-year survival rate, local or distant metastases can be observed in 20%. It is essential to recognize other factors associated with malignancy and poor prognosis. Vitamin D and its deficiency has proven useful as a prognostic biomarker for many types of cancer, including thyroid cancer. Aim: Evaluate the relationship between vitamin D status in DTC and benign thyroid disorders patients and correlation between vitamin D and histopathological findings in DTC group. Methods: Study included 170 patients with confirmed DTC and 200 with benign thyroid pathology. Evaluation included 25-hydroxy vitamin D [25(OH)D], ultrasound and histopathologic features. Results: In DTC patients, mean value of vitamin D was significantly lower (17.86 ng/mL ± 9.31 DS versus 20.26 ng/mL ± 9.31 DS, p=0.029). Statistical analysis confirmed a negative correlation between vitamin D levels and tumor size (T) according to TNM classification (r=-0.176, p=0.02). Conclusions: Vitamin D level was significantly lower in the DTC group and 25(OH)D levels may be correlated with histopathology features like tumor size and aggressiveness according to TNM classification.
