Percutaneous intranodular ethanol injection: a new treatment for autonomous thyroid adenoma

Established methods for definitive ablation of autonomous thyroid nodules are surgery and radioiodine. Since it has been demonstrated that percutaneous ethanol injection can inactivate parathyroid adenomas and small hepatocellular carcinomas, we started a trial of this treatment in patients with autonomous thyroid nodules. Twenty-eight patients, 22 toxic and 6 nontoxic, all with undetectable thyrotropin serum levels and suppressed extranodular tissue on scintigraphy, were treated. Treatment consisted of percutaneous intranodular ethanol injection under ultrasound guidance. The total amount of alcohol injected ranged from 0.4 to 2.2 times the estimated nodule volume, divided into 4 to 9 injections performed at 2 to 7 day intervals. Most patients were treated with a single cycle of injections, but 7 of them required 2 cycles. The signs and symptoms of hyperthyroidism disappeared in all cases. Apparently complete cure (normal serum free thyroid hormones, thyrotropin in basal conditions and after thyrotropin releasing hormone, reactivation of extranodular tissue on scintigraphy with nodule no longer visible) was obtained in 17 patients (13 after 1 cycle and 4 after 2 cycles). Partial cure (normal serum free thyroid hormone levels, detectable thyrotropin levels with normal or blunted response to thyrotropin releasing hormone and partial reactivation of extranodular tissue on scintigraphy with nodule or parts of it still visible) was obtained in 10 patients (8 after 1 cycle and 2 after 2 cycles). In 1 patient with a very large nodule thyrotropin levels remained undetectable, but thyroid hormone levels eventually became normal. No recurrences were observed after a follow-up of 12 to 32 months (mean 20 months). No serious side effects were encountered. A clinically valuable result was obtained in all patients. These data suggest that this form of treatment could constitute an alternative to surgery and radioiodine for the ablation of autonomous thyroid nodules.