Endocrine Abstracts

Levothyroxine suppression therapy, i.e. keeping the TSH value below 0.3 mIU/l with the aim to reduce the total thyroidal tissue or nodule volume, is an arguable and controversial issue not only due to the effect upon nodule volume but also because of the extent of necessary suppression, the effect of incomplete suppression, long-time therapeutic effects and risk of cardiovascular problems and osteoporosis.

The incidence of nodular alterations rises with age and in patients under the age of 20 show higher malignity risk. Fine needle aspiration biopsy (FNAB) is a safe and cost-efficient method of evaluating the biological character of nodules and choosing between a conservative and surgical treatment.

In our study, we investigated nodular alterations in patients under the age of 40, evaluated malignity presence by FNAB and observed the examined nodules in treated/untreated groups for at least 1 year. The objective was to set up the criteria that can predict nodular alterations in young patients and evaluate the benefit of suppression therapy.

The 3-year (2009–2011) prospective randomized study included 78 individuals, 65 of which accomplished observation: 32 treated and 33 untreated.

The treated/untreated variances were tested using ANOVA with repetition with the following factors: group, phase, subject and interaction, which evaluates variances in time.

Our results did not confirm statistically significant reduction of nodules in patients under the age of 40 subjected to 1-year suppression therapy compared to the untreated group. The input values of all patients before treatment showed statistically significant negative correlation between the nodules size and TSH value.

The conclusion of our study is that patients suffering from thyroidal nodular alterations can be left untreated, upon FNAB evaluation, for minimum of 1 year.

Supported by MO ČR 8130 Grant.