RESUMO
OBJECTIVE: To report data regarding treatment with use of percutaneous laser ablation (PLA) in autonomously functioning thyroid nodules (AFTN). METHODS: We treated 18 patients (10 women and 8 men, 31 to 80 years old) who presented with a single hyperfunctioning thyroid nodule (8 patients) or a multi-nodular goiter (10 patients) with clearly hyperfunctioning areas on a thyroid scintiscan. In 5 cases, free thyroxine (FT4) and free triiodothyronine (FT3) levels were high, and in these patients and a further 9 patients with cardiovascular symptoms, methimazole therapy was initiated to restore euthyroidism. The total number of PLA sessions ranged from 1 to 5 (median, 3). Thyroid-stimulating hormone, FT4, FT3, thyroglobulin, and antithyroglobulin and anti-thyroid peroxidase antibodies were measured by a commercial kit the day after PLA treatment, then weekly during the first month, and monthly thereafter. The Student t test was used for statistical analyses, and data are reported as mean values +/- SE. RESULTS: After each PLA session, there was a transient and mild increase in FT4 and FT3-5.2% to 18.1% (mean, 11.1 +/- 0.69%) (P<0.001) in patients not treated with methimazole and 4.0% to 8.3% (mean, 5.9 +/- 0.31%) (P<0.001) in patients treated with methimazole-relative to values before treatment; however, these values never reached the range of hyperthyroidism. In addition, thyroglobulin showed a remarkable increase after 24 hours- 115% to 390% (mean, 266.0 +/- 12.7%) (P<0.001). Thyroid-stimulating hormone increased in all cases and reached normal values in all patients with single AFTN and in 5 patients (50%) with multinodular goiter within 3 months after PLA. At 1-year follow-up, the decrease in nodular volume was 24% to 72% (mean, 59.3 +/- 8.2%; P<0.001). CONCLUSION: Our data show that PLA can be a useful treatment in AFTN and particularly in single toxic nodules. Possible elective indications are patients who refuse surgical or radioiodine treatment and patients with cardiovascular comorbidity who need rapid restoration of the euthyroid state and who cannot tolerate the discontinuation of antithyroid drugs for radioiodine treatment.
