Journal of Korean Endocrine Society 2002;17(1):57-68.
Published online February 1, 2002.
Percutaneous Ethanol Injection in Autonomous Functioning Thyroid Nodules and Complex Cysts: Five Years' Experience.
Seong Jin Lee, Jung Hee Han, Ha Young Kim, Jong Chul Won, Sang Wook Kim, Ho Kyu Lee, Il Min Ahn
1Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
2Department of Diagnostic Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Percutaneous ethanol injection therapy (PEI) performed with ultrasonography guidance has recently been used in cases of autonomous functioning thyroid nodules (AFTN) and benign complex cysts. We performed this study to analyze the effects of PEI on AFTN and benign complex cysts. METHEODS: From September 1995 to September 2000, we performed PEI on 456 outpatients (47 men and 409 women, mean age 42.4+/-11.8 years) with AFTN or benign complex cysts. All cases were subjected to fine needle aspirations (FNA) by ultrasonography-guidance if necessary. FNA was performed at least twice with results of colloid nodule in cases of complex cysts. For AFTN, cases with FNA results of follicular neoplasm were also included. After PEI on AFTN, patients were classified into three response groups: complete response as judged by our new criteria (CR, normalization of TSH and free T4, disappearance of hot nodule on thyroid scan) along with the old criteria of previous studies (normalization of TSH and free T4, recovery of suppressed extranodular tissue on thyroid scan), partial response (PR, normalized free T4 but suppressed TSH, persistent hot nodule despite recovery in suppressed extranodular tissue) and no response (no change of hot nodule). Complex cysts were classified into three groups in accordance with volume reduction after PEI: complete response (CR, above 90% of volume reduction), partial response (PR, 50~89%) and no response (below 50%). RESULTS: Overall pre-treatment volumes were 15.3+/-12.1 mL and post-treatment volumes were 2.8+/-2.9 mL, with 66.4+/-19.9% of volume reductions in AFTN and complex cysts. Volume reductions were 71.5+/-18.0% in AFTN, and 66.1+/-15.0% in complex cysts. In 24 cases of AFTN, responses satisfying the previous criteria were 14 (58.3%) of CR, 6 (25.0%) of PR, and 4 (16.7%) of no response. However, by the new criteria there were 1 (4.2%) of CR, 10 (41.6%) of PR, and 13 (54.2%) of no response. In 432 cases of complex cysts, CR was observed in 82 (19.0%), PR in 261 (60.4%) and no response in 89 (20.6%). The volume reductions in complex cysts with pre-treatment volume larger than 15 mL were higher than those of groups with smaller volumes (p<0.001). Pre-treatment volumes were not correlated with post-treatment volumes, nor with volume reductions. Volume reductions were not correlated with the amounts of injected ethanol. Mild and transient complications were observed in 41 cases (9.0%) during PEI, consisting of transient neck pain (n=36, 7.9%), transient unilateral vocal cord palsy (n=3, 0.7%), intracavitary hemorrhage (n=1, 0.2%), and transient hypotension (n=1, 0.2%). CONCLUSION: Our data suggest that the efficacy of PEI on AFTN is temporary and does not usually induce long-term complete remissions. In complex cysts, however, PEI may have potential as an additive treatment modality to thyroid hormone suppressive therapy
Key Words: Autonomous Functioning Thyroid Nodule (AFTN), Benign Complex Cyst, Percutaneous Ethanol Injection Therapy (PEI)

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