Long-term efficacy evaluation of a protocol for the management of symptomatic thyroid cysts with ultrasound-guided percutaneous ethanol injection

AIM:To evaluate the long-term efficacy of percutaneous ethanol injection treatment (PEIT) as an alternative to thyroid surgery in symptomatic thyroid cysts. PATIENTS AND METHODS:100 subjects (48±12 years; 58% women) with symptomatic thyroid cysts relapsing after drainage were prospectively included. PEIT was conducted using an established procedure, and the initial cyst volume, symptoms and pain perceived by the patient were assessed. The volume of instilled alcohol was ≤2ml without re-extraction in all cases. Patients were followed-up for more than 3 years and final cyst volume and symptom improvement were assessed. RESULTS:Mean maximum cyst diameter before drainage was 3.1±1.2cm. In 71% of patients ≤2 PEIT sessions were required. Median maximum cyst volume was 12.7 (5.4-21.7)ml before the first drainage and median total volume extracted from the cysts was 13.0 (6.2-37.0)ml. After a mean follow-up period of 52±10 months, 98% of patients reported a complete absence of symptoms. The final median volume for the whole group was 0.8 (0.1-2.0)ml with a median volume reduction of 94 (81-99)%. A final volume reduction greater than 65% was observed in 90% of cases. Reported pain during the procedure was absent or mild in 76.4% of cases. CONCLUSIONS:PEIT is a safe and well-tolerated first-line treatment for symptomatic thyroid cysts with long-term effectiveness.