Efficacy Assessment and Analysis of Related Factors of Ultrasound‐Guided Percutaneous Lauromacrogol Injection for Cystic Thyroid Nodules

Objectives This study aimed to investigate the factors influencing the short‐term and long‐term efficacy of sclerotherapy for cystic thyroid nodules. Methods Ninety‐nine cystic thyroid nodules that underwent ultrasound‐guided fine‐needle aspiration biopsy, detection of thyroglobulin in fine needle aspirate (Tg‐FNA), and ultrasound‐guided percutaneous lauromacrogol injection were retrospectively enrolled from July 2018 to July 2021. All nodules were followed up at 3 and 12 months after the procedure. Factors related to lauromacrogol injection efficacy, including initial volume, vascularity, pathological types, and Tg‐FNA level, were analyzed. The nodules were classified as non‐effective (VRR <50%) and effective groups (VRR ≥50%) at 3 months to evaluate short‐term prognosis, and non‐cured (VRR <90%) and cured groups (VRR ≥90%) at 12 months to evaluate long‐term prognosis. Results The volume of cystic thyroid nodules tended to shrink during follow‐up. The resolution rate was 79.80% (79/99) at 3 months and 96.91% (94/97) at 12 months. The cure rate was 80.41% (78/97) at 12 months. Independent factors for the long‐term prognosis included Tg‐FNA level and vascularity ( P < .05). Only Tg‐FNA level was an independent factor for the short‐term prognosis ( P < .05). The area under the receiver operating characteristic curve for assessing the efficacy at 3 months was 0.79 (95% confidence interval [CI]: 0.65–0.89). With a cutoff value of Tg‐FNA 126.92 ng/mL, the specificity was 0.70, and the sensitivity was 0.85. Conclusions Ultrasound‐guided percutaneous lauromacrogol injection is an effective treatment option for cystic thyroid nodules. It is less effective in viscous or vascular predominantly cystic nodules.