Endocrine Abstracts

Introduction: Minimally-invasive management of thyroid nodules has recently garnered limelight as a treatment strategy. The first-line treatment for benign cystic and predominantly-cystic nodules with symptoms/cosmetic concerns includes aspiration, associated with high recurrence rates. This study was conducted to determine the efficacy and safety of percutaneous ethanol injection (PEI) for the treatment of cystic and predominantly-cystic thyroid nodules.

Methods: Retrospective analysis was performed of 35 patients with cystic and predominantly-cystic (>50%) thyroid nodules who were treated using ultrasound-guided PEI between January 2020 to April 2022. All patients underwent fine needle aspiration (FNA) of their cyst demonstrating benign pathology (Bethesda II). The main outcomes were efficacy, defined as reduction in nodule volume of ≥50%, and safety, defined as no or minor adverse events. Patients were assessed at post-procedure months 1, 6, and 12.

Results: Thirty-five patients (32 females) underwent ultrasound-guided PEI for the treatment of cystic and predominantly-cystic thyroid nodules. Mean age was 35.6 years (19-56). All patients were euthyroid. The median largest diameter of the thyroid nodule was 4.5 cm (3.2-8.0); the median volume pre-PEI and post-PEI on last follow-up was 16.6 ml (2.6-108.1) and 3.98 ml (0.32-40) respectively. All patients had a 50% or greater reduction in nodule volume, with median volume reduction of 76% (0-97%). Three patients had recurrence. The procedure was well-tolerated by all patients. Adverse effects occurred in 4 patients (11.4%) and were mild and temporary (pain and bleeding into the cyst). The pericapsular infiltration with xylocaine pre-procedure could be the reason for less pain during and post-procedure. The injected ethanol was not reaspirated and could explain the greater volume reduction in this study.

Conclusion: Ultrasound-guided PEI appears to be a safe and effective alternative to surgical resection for patients with benign cystic and predominantly cystic thyroid nodules with pressure effects or cosmetic concerns.