PERCUTANEOUS ETHANOL INJECTION TREATMENT OF AUTONOMOUSLY FUNCTIONING SINGLE THYROID-NODULES - OPTIMIZATION OF TREATMENT AND SHORT-TERM OUTCOME

Twenty-five patients with solitary autonomous thyroid nodules (15 non-toxic, 10 toxic) received percutaneous ethanol injection treatment (PEIT) under sonographic guidance in 4-7 sessions (1-2 weekly). To test different doses, smaller nodules (volume < 15 mL) were given 0.75-2.8 mL ethanol/mL nodular tissue while larger nodules received 0.5-1 mL/mL. Except for 1 patient who developed hyperpyrexia, no relevant adverse effects were observed. A slight, asymptomatic increase in serum thyroid hormone levels was observed in both groups during the treatment. Three months after treatment, a biochemical and clinical remission of hyperthyroidism was observed in 8 of 10 patients with toxic nodules. A significant increase of TSH level was seen in both groups (p < 0.01). Significant shrinkage of volume (p < 0.001) as well as structural alterations of nodules were consistently recorded at sonography. A linear relationship (r = 0.98; p < 0.0001) between pretreatment volume and volume reduction was found both for large and small nodules, thus suggesting that even limited ethanol doses may be therapeutically effective. A recovery of extranodular parenchyma activity at scintiscan occurred in 16 (64%) of 25 patients. These data confirm that PEIT is effective in obtaining functional ablation and in inducing remission of hyperthyroidism. Adverse effects are infrequent. In spite of the small patient sample, a 0.5-1 mL ethanol dose per each mL of tissue appears as effective as larger doses and seems appropriate for treatment.