PURPOSE: Radiofrequency ablation (RFA) has been used to treat various malignant tumors. The purpose of this retrospective study was to present the therapeutic effect of RFA for locally recurrent thyroid cancers in both radiological and endocrinological aspects.
MATERIALS AND METHODS: The institutional review board approved this study, and informed consent was waived. Between February 2008 and June 2011, 24 patients (6 men, 18 women; mean age, 51.7 years) with 32 recurrent thyroid cancers (mean diameter, 8.1 mm; range, 2–15 mm) were included in this study with the following criteria:(1) 3 or fewer recurrences of well differentiated thyroid cancer (2) no recurrence other than target lesions for RFA (3) patients who were ineligible for surgery (4) 1 year or more of follow-up after RFA. All of the recurrences were neither palpable nor symptomatic. Under the guidance of ultrasound, they were ablated by using radiofrequency generator and 18-gauge internally cooled electrodes with a 7-cm shaft length and 0.5 cm active tip. During 25.6 ± 8.6 months (range, 12–48 months) follow-up, the changes on ultrasound, CT, and laboratory were evaluated.
RESULTS: Twenty out of the 24 patients (83.3%) and 30 out of the 32 lesions (93.8%) were treated in a single RFA session. Two patients required an additional RFA session each because of multiplicity of the tumors in 1 patient or a newly developed recurrence during follow up period in 1. The remaining 2 patients required repeated RFA session for the initially ablated lesion each because it was proved to have malignant cells on cytology 1 year after RFA. Along with significant reduction of volume (98.1 ± 7.3 %, p < 0.0001) in all recurrences, 27 recurrences (84.4%) disappeared completely on CT in addition to ultrasound. Of the 23 patients without serum-thyroglobulin antibodies, the serum-thyroglobulin was undetectable at both initial and last follow-up evaluation in 7 patients (7/23) and decreased at last follow-up evaluation in 11 patients (11/23). There was no complication other than transient hoarsenesses in 2 patients.
CONCLUSION: RFA appears to be a valuable alternative option for controlling asymptomatic small recurrent thyroid cancers in the patients who are poor surgical candidates.
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SS 07 TH-06.pdf
