The two-year results of using radiofrequency ablation as a novel treatment for persistent or relapsed Graves' disease, a prospective study.

Objectives Graves' disease(GD) is the most common cause of hyperthyroidism. Antithyroid drug(ATD) is the first-line treatment but when discontinued, >50% of patients suffer relapses. Conventional definitive treatment options include surgery and radioiodine therapy(RAI), each with its own disadvantages. Radiofrequency ablation (RFA) achieved promising short-term remission rates in a previous pilot study. The current study reports our experience of using RFA to treat relapsed GD from the largest cohort of patients with longer period of follow-up. Methods This single-arm prospective study recruited consecutive patients aged ≥18 with persistent / relapsed GD requiring ATD from two tertiary endocrine surgery centers. Those with compressive goiter, suspected thyroid malignancy, moderate to severe Graves' ophthalmopathy, preferred surgery/RAI or pregnant were excluded. Eligible patients received ultrasound-guided RFA to the entire bulk of the thyroid gland. ATDs were discontinued afterwards and thyroid function tests were monitored bi-monthly. The primary outcome was disease remission rate at 24-months follow-up after single-session RFA, defined as being biochemically euthyroid or hypothyroid without ATD. Secondary outcomes were complication rates. Results Of the 100 patients considered, 30 (30.0%) patients were eligible and received RFA. Most were female patients (93.3%). The median total thyroid volume was 23mL (15.9 - 34.5). All completed 24-months follow-up. After single-session RFA, disease remission rates were 60.0% at 12-months and 56.7% at 24-months. Amongst the 13 patients with relapse after RFA, 9 (69%) required lower ATD dose than before RFA; 2 received surgery without complications. Total thyroid volume was the only significant factor associated with relapse after RFA (OR 1.054, 95% CI 1.012 - 1.099, p=0.012). At 24-months, RFA led to disease remission in 100% of the 9 patients with total thyroid volume <20ml, and 35% of patients with total thyroid volume ≥20ml (p=0.007). There was no vocal cord palsy, skin burn, hematoma, or thyroid storm after RFA. Conclusions In a highly selected group of patients with relapsed GD and predominantly small thyroid glands, single-session RFA may achieve disease remission. Smaller total thyroid volume may be a favorable factor associated with disease remission after RFA. The results of this study need to be confirmed with a long-term clinical trial.

Efficacy of single-session radiofrequency ablation (RFA) in rendering euthyroidism for persistent/relapsed Graves' disease, a pilot study.

OBJECTIVES: Graves' disease (GD) is the most common cause of hyperthyroidism. Antithyroid drug (ATD) is often the first-line treatment but > 50% patients suffer a relapse when ATD is discontinued. Surgery or radioiodine remains the current options of definitive treatment in these patients. This pilot study examined the short-term efficacy of single-session thyroid radiofrequency ablation (RFA) as a novel definitive treatment for persistent/relapsed GD. METHODS: Consecutive patients with persistent/relapsed GD requiring ATD were considered. Those with a clear surgical indication, either thyroid lobe volume ≥ 20 mL; those who were pregnant or lactating; and those who had any severe medical conditions that would pose extra treatment risks were excluded. Eligible patients received ultrasound-guided RFA of the entire bulk of thyroid gland. Thyroid function tests were monitored bi-monthly. The primary outcome was disease remission rate, defined as a state of biochemical euthyroidism or hypothyroidism without ATD. Secondary outcomes were complication rates. RESULTS: Of the 68 patients considered, 15 (22.1%) patients were eligible. Most were females (93.3%). The median age was 37 (IQR 31-48) years old. The disease remission rates were 79.0% at 6 months and 73.3% at 12 months. Among the 4 patients who relapsed after RFA, three required less ATD dose than before RFA. RFA was well-tolerated in the ambulatory setting. There were no vocal cord palsy, skin burn, hematoma, or thyroid storm after RFA. CONCLUSIONS: In well-selected patients, single-session RFA of the thyroid gland may be a potential treatment for patients with persistent/relapsed GD. It is a safe and well-tolerated ambulatory procedure. KEY POINTS: • Radiofrequency ablation of the thyroid gland is an efficacious treatment for persistent/relapsed Graves' disease in well-selected patients. • Radiofrequency ablation of the thyroid gland for the treatment of persistent/relapsed Graves' disease is a safe and well-tolerated ambulatory procedure. • Radiofrequency ablation of the thyroid gland may be a potential alternative treatment for well-selected patients with persistent/relapsed GD who do not wish to undergo either thyroidectomy or radioactive iodine or continue antithyroid drugs.

A prospective follow-up of thyroid volume and thyroiditis features on ultrasonography among survivors of predominantly mild to moderate COVID-19.

Background: We previously showed that higher SARS-CoV-2 viral load correlated with smaller thyroid volumes among COVID-19 survivors at 2 months after acute COVID-19. Our current follow-up study evaluated the evolution of thyroid volumes and thyroiditis features within the same group of patients 6 months later. Methods: Adult COVID-19 survivors who underwent thyroid ultrasonography 2 months after infection (USG1) were recruited for follow-up USG 6 months later (USG2). The primary outcome was the change in thyroid volume. We also reassessed thyroiditis features on USG, thyroid function and anti-thyroid antibodies. Results: Fifty-four patients were recruited (mean age 48.1 years; 63% men). The mean thyroid volume increased from USG1 to USG2 (11.9 ± 4.8 to 14.5 ± 6.2 mL, p < 0.001). Thirty-two patients (59.3%) had significant increase in thyroid volume by ≥15%, and they had a median increase of +33.3% (IQR: +20.0% to +45.0%). Multivariable logistic regression analysis showed that only higher baseline SARS-CoV-2 viral load independently correlated with significant thyroid volume increase on USG2 (p = 0.022). Among the seven patients with thyroiditis features on USG1, six (85.7%) had the features resolved on USG2. None had new thyroiditis features on USG2. All abnormal thyroid function during acute COVID-19 resolved upon USG1 and USG2. Conclusion: Most COVID-19 survivors had an increase in thyroid volume from early convalescent phase to later convalescent phase. This increase correlated with high initial SARS-CoV-2 viral load. Together with the resolution of thyroiditis features, these may suggest a transient direct atrophic effect of SARS-CoV-2 on the thyroid gland with subsequent recovery of thyroid volume and thyroiditis features.