Background: Radiofrequency ablation(RFA) has been advocated as an alternative to radioiodine and/or surgery for the treatment of autonomously functioning benign thyroid nodule (AFTN). However, only a few studies have investigated the efficacy of RFA on AFTN. Furthermore, these studies are characterized by several biases about patient selection, number of RFA treatments, short clinical and radiographic follow-up. A recent prospective 12-month study has demonstrated that one single RFA treatment was able to withdraw anti-thyroid medication in 50% of the hyperthyroid patients who remained euthyroid afterwards. However, no defined pre-treatment factors able to predict the response to the RFA in Treating AFTN have been clearly identified.
Aim: To evaluate the success rate of RFA to restore euthyroidism in a cohort of adult patients with small solitary AFTN compared to medium-larger ones. Secondary end-points included volume reduction and conversion rate from hot to cold nodules at thyroid scintiscan.
Methods: This was a 24-month prospective monocentric open parallel-group trial. Twenty-nine patients with AFTN were divided into two groups based on thyroid volume: 15 patients with small nodules (<12 ml) in group A and 14 patients with medium nodules (>12 ml) in group B. All patients underwent a single session of RFA and were clinically, biochemically and morphologically evaluated at baseline and at 1, 6, 12 and 24 months after treatment. At the end of the study period, a thyroid scintiscan was performed.
Results: After RFA, there was a larger volume reduction in group A compared to group B (P<0.001 for each follow-up point). After RFA, there was greater nodule volume reduction in group A compared with group B (P<0.001 for each follow-up point). In group A, there was a greater increase in TSH levels than in group B at 6 (P=0.01), 12 (P=0.005) and 24 months (P<0.001). At 24 months, the rate of responders (subjects with euthyroidsm without metimazole) was greater in group A than in group B (86 vs 45%; P<0.001). At 24 months in group A, 86% of nodules converted from hot to cold compared with 18% in group B (P<0.001).
Conclusions: This study shows that a single RFA was effective in restoring euthyroidsm in patients with AFTN, mainly in small nodules. Nodule volume seems to be a significant Predictive Factor of Efficacy of RFA in Treating AFTN. Larger prospective studies are needed to confirm our findings.
19 May 2018 - 22 May 2018