Outcomes and Risk Factors for Complications of Laser Ablation for Thyroid Nodules: A Multicenter Study on 1531 Patients

Background: Image-guided laser ablation therapy (LAT) of benign thyroid nodules demonstrated favorable results in randomized trials with fixed modalities of treatment. The aim of this retrospective multicenter study was to assess the effectiveness, tolerability, and complications of LAT in a large consecutive series of patients from centers using this technique in their routine clinical activity. Patients: Clinical records of 1534 consecutive laser-treated nodules in 1531 patients from eight Italian thyroid referral centers were assessed. Inclusion criteria were as follows: solid or mixed nodules with fluid component up to 40%; benign cytological findings; and normal thyroid function. Methods: LAT was performed with a fixed-power protocol, whereas the number of applicators and illumination times were different according to target size. From one to three illuminations with pull-back technique and with a total energy delivery based on the nodule volume were performed during the same session. Patients were evaluated during LAT, within 30 days, and 12 months after the procedure. Results: Total number of treatments was 1837; 1280 (83%) of nodules had a single LAT session. Meannodule volume decreased from 27 +/- 24mLat baseline to 8 +/- 8mL 12 months after treatment (P < .001). Mean nodule volume reduction was 72% +/- 11% ( range 48%-96%). This figure was significantly greater in mixed nodules (79% +/- 7%; range 70%-92%) because they were drained immediately before laser illumination. Symptoms improved from 49% to 10% of cases (P < .001) and evidence of cosmetic signs from 86% to8% of cases (P < .001). Seventeen complications (0.9%) were registered. Eight patients (0.5%) experienced transitory voice changes that completely resolved at the ear-nose-throat examination within 2-84 days. Nine minor complications (0.5%) were reported. No changes in thyroid function or autoimmunity were observed. Conclusions: Real practice confirmed LAT as a clinically effective, reproducible, and rapid outpatient procedure. Treatments were well tolerated and risk of major complications was very low.