Two-year outcomes of single-session high-intensity focused ultrasound (HIFU) treatment in persistent or relapsed Graves’ disease

Abstract

Objective: To evaluate the longer-term disease relapse of ultrasound (US)-guided high-intensity focused ultrasound (HIFU) ablation as a treatment for persistent/relapsed Graves’ disease (GD). Methods: After ethics approval, consecutive patients with persistent or relapsed GD who underwent bilateral US-guided HIFU ablation from 2016 to 2017 were retrospectively analyzed. Altogether, 75 patients received HIFU ablation of the central portion of the right and left thyroid lobes with areas near the trachea–esophageal groove and common carotid artery un-ablated. They were followed for 24 months or longer. Baseline thyrotropin (TSH), free T4, anti-thyroid autoantibodies, and TSH receptor (TSHR) antibody were checked. Primary outcome was the 24-month relapse rate. Relapse referred to hyperthyroidism (free T4 (FT4) > 23 pmol/L) afterwards. Variables associated with relapse were analyzed by binary logistic regression. Results: The cohort comprised mostly females (84.0%) with a mean age of 42.05 ± 10.74 years. The 24-month relapse rate was 41.3% with 31 patients suffering a relapse. No patient suffered from hypothyroidism. Three patients (4.0%) suffered from temporary vocal cord palsy but these injuries recovered spontaneously after 2 months. In univariate analysis, higher daily dose of carbimazole (OR = 1.125, 95% CI = 1.023–1.237, p = 0.015) and higher baseline TSHR level (OR = 1.085, 95% CI = 1.022–1.152, p = 0.007) were significant factors for disease relapse. In the multivariate analysis, higher baseline TSHR level was a significant independent factor for disease relapse within 24 months (OR = 1.079, 95% CI = 1.014–1.148, p = 0.016). Conclusions: US-guided HIFU of the thyroid gland was a safe and relatively efficacious treatment in the longer term for patients with persistent or relapsed GD. Key Points: • US-guided HIFU ablation is relatively efficacious in the longer term. • US-guided HIFU ablation of the thyroid is safe. • Higher TSHR level may lead to higher disease relapse after treatment.