Endocrine Abstracts

Background/aim: We aimed to determine the effect of percutaneous ethanol injection (PEI) on volume of cystic and mixt thyroid nodules, thyroid function tests (TFTs), antibody titers and cytological changes for 1 year.

Methods: Fifty-five nodules of 53 patients with cystic and mixt properties treated with PEI were included. Nodule volumes, TFTs, thyroid autoantibodies were analyzed at baseline, 6^th and 12^th months. Fine needle aspiration biopsy (FNAB) was performed to PEI applied nodules in the 12^th month. Thyroid nodules were grouped into three by structural properties (pure cystic, predominant cystic, predominant solid). By calculating volume reduction between initial and final volume, we defined response to PEI in three categories as complete response (≥90%), partial response (<90% to ≥50), and no response (<%50).

Results: PEI caused a volume reduction of 80.7% at 6^th month and 82.1% at 12^thmonth without any serious complication. PEI was repeated 1.4±0.4 times with a mean total ethanol amount of 3.6±3.1 ml. Volume reduction in the pure cystic nodules at 6th and 12th months after PEI was greater than the volume reductions in predominant cystic and predominant solid nodules. We detected that smaller nodules have greater volume reductions after PEI at 12th month. During the study, patients remained euthyroid. Anti-thyroglobulin levels were decreased at 12^th months. None of the FNAB results was compatible with a malignant or suspicious for malignancy cytology at 12^thmonth.

Conclusion: PEI is an effective way of treatment for benign cystic and mixt thyroid nodules without any serious side effects. We can also assume that PEI is not a trigger for autoimmunity and carcinogenesis for short term.