Endocrine Abstracts

Introduction

Both vitamin D insufficiency and multinodular goiter (MNG) are widespread throughout the world, with Romanian population being no exception. However, at this point in time there is insufficient data whether there is a connection between the two or is it just a coincidence. The aim of this study is to evaluate whether there is a relationship between serum level of 25-hydroxyvitamin D (25OHD) and the risk of differentiated thyroid cancer (DTC) in patients with multinodular goiter.

Materials and methods

we performed a retrospective study which included 129 patients evaluated for euthyroid nodular goiter in a tertiary Endocrinology Department. Patients ages ranged between 18-79 years, with exclusion criteria as follows: hypo/hypercalcemia, associated endocrinopathies (excepting: diabetes, obesity, primary osteoporosis, hyperparathyroidism due to vitamin D deficiency, adrenal incidentalomas, non-functioning pituitary adenomas without pituitary disfunction), active cancer, drugs (glucocorticoids, vitamin D supplements). Laboratory evaluations included a CBC, ESR, biochemistry, TSH, fT4, 25OHD levels and a FNA, if indicated. We investigated the differences between replete and non-replete vitamin D groups, Bethesda risk groups, and correlations using SPSS 26.0.

Results

Out of the 129 patients with euthyroid MNG, 95 (73.6%) had their vitamin D levels tested with a median value of 22.30 (13.19) ng/ml. Seventy five% of the patients presented vitamin D insufficiency (10–30 ng/ml), whereas 6.25% of patients had vitamin D deficiency (<10 ng/dl). Chi-square tests showed no differences regarding the Bethesda risk among the groups defined as vitamin D replete (>30 ng/ml) (n = 18) and non-replete (n = 78) (P = 0.445). Patients were divided in two groups: group 1 (n = 111) with Bethesda I-III, including those without a FNA indication, and group 2 (n = 18) with Bethesda classification ranging from IV to VI. Patients in group 2 were younger (p 0.043) and had a higher TSH level (p 0.028) than patients in group 1. The two groups were similar in terms of serum level of 25OHD (p 0.445). TSH levels correlate with a Bethesda risk above IV in MNG patients in Kendall’s tau correlation (p 0.028).

Conclusions

our study did not find a relationship between serum level of 25OHD and an increased risk for DTC evaluated by Bethesda classification system. Higher TSH levels were associated with a higher risk for DTC. We recommend further research to this matter.