Endocrine Abstracts

Objectives: Image-guided thermal-ablation (LTA; RFA) are well established therapy options in selected BTN. PMWT is a mini-invasive technique recently applied in thyroid disease; aim of this work is investigate its effectiveness as treatment in BTN.

Methods: From May 2021, 45 patients (30 F, 15 M, Aged 37-90, Mean 55,8) with BTN symptomatic/in growing, refusing/non eligible to surgery were enrolled. Inclusion criteria: nodule diameter ≥ 2 cm, mainly solid ≥ 20%, 2 FNA cytology pathologically confirmed as benign (TIR2 sec ITCCS 2014). Baseline were performed ECG, anesthesiology and ENT consults, laboratory assessment (serum levels of fT3, fT4, TSH, TPOAb, TgAb, calcitonin, blood count, clotting indexes). Additionally 25/45 pts done Thyroid Scintiscan with 99mTc-Pertecnetate (19 cold 3 hot no; 3 non focal findings). Ultrasound-guided PMWTA was carry out under local anesthesia through TATO antenna (18G x8 cm/17G x10 cm Terumo) delivering 10-15 W in 10-15 minutes, depends on the Volume of BTN. Physician effects an anamnestic evaluation, thyroid physical examination rating symptomatology with a Compressive Score (CS on a 10 cm visual-analog scale), assigned an Aesthetic Score (AS from 1-no palpable-visible nodule to 4 palpable-visible in all positions). US thyroid scan was performed to record Volume of BTN target (VnT) baseline and during follow-up scheduled at 1,3,6 months after procedure. Additionally volume reduction rate % (VRR) was calculated, and success rate fixed in a volume reduction ≥ 50%.

Results: No peri-procedural major complications were observed. 1/45 has developed in 10 days after PMWT transient thyrotoxicosis and atrial fibrillation pharmacologically reverted. 10 patients still missing the follow-up; the data will be available and presented during the meeting. Clinically was registered CS mean score from 4,2 (baseline) to 3 and 1,7 (1 and 3 months respectively), AS from 3,2 (baseline) to 2 (1 and 3 months). Interestingly boths scores were stable at 6 months follow-up. Baseline mean VnT was 17,29 mL (range 77-1,6 mL) and mean VnT post-procedure was 8,79 mL (range 32,9-0,31mL). The estimated mean VRR at 1,3 6 months was 52% (range 12- 82%),58%(range 45-91%), 66% (range 45-94%), respectively. If consider as a therapeutic goal a volume reduction of ≥ 50 % the success rate was approximately 82,9%. Neither a re-growth occurred in this short-term evaluation.

Conclusion: In BTN disease use of PMWT has shown effective nodule shrinking, well tolerated, safe and with low complication rate. Furthemore we registered a satisfactory clinical response. Our data need a validation in large series and long term follow-up.