Treatment of hyperfunctioning thyroid nodules with percutaneous ethanol injection: Eight years' experience

The aim of our study was to define the long-term efficacy and safety of per cutaneous ethanol injection (PEI) for the treatment of autonomous thyroid n odule (ATN), and to optimise the clinical usefulness of such a therapy. We treated 132 patients with ATN (30 M and 102 F, aged 47.5+/-12.9 years; m ean+/-SD), in case other established treatments were refused or contraindic ated. Eighty-five patients were affected by toxic adenoma and 47 suffered f rom pre-toxic nodules. Ethanol was administered weekly under sonographic co ntrol, in 7 sessions (range 2-16). During PEI treatment, 26 toxic elderly p atients were treated with methimazole and propranolol. Three possible outco mes were identified for statistical analysis: failure (persistent suppressi on of extra nodular tissue uptake, along with elevated free thyroid hormone and undetectable TSH levels); partial cure (normal free thyroid hormone an d low/undetectable TSH levels); complete cure (normal thyroid hormone and T SH levels; restored extra nodular uptake). The patients were followed for u p to 8.5 years (median 76 months). PEI therapy was well tolerated by all pa tients though a mild to moderate local pain occurred in about 30% of sessio ns. Complete cure was achieved in all pre-toxic patients and in 60 (70.6%) patients with toxic adenoma, while partial cure was observed in 11 cases (1 2.9%) and failure in 14 (16.5%). A significant shrinkage of nodule volume w as observed in all patients (p = 0.0001), while those with toxic nodules la rger than 30 mt showed a significantly lower response rate to PEI (p < 0.05 ). At controls, only one patient developed subclinical hypothyroidism while , among partially cured patients, five relapsed. The administration of meth imazole and/or propranolol did not modify PEI outcome. In conclusion, we suggest that PEI therapy may be the treatment of choice i n patients with pre-toxic thyroid adenoma - where therapy is least necessar y- despite the nodule volume. Though ethanol injection therapy of toxic thy roid nodules may be troublesome for the need of multiple sessions, it appea rs an effective alternative procedure in patients at poor surgical risk, an d in younger patients in whom radioiodine is contraindicated. Since a speci al technical skill in intervention procedures is required PEI therapy may b e suitable only for patients living nearby a trained centre.