Efficacy and safety of percutaneous ultrasound guided radiofrequency ablation for treating cervical metastatic lymph nodes from papillary thyroid carcinoma.

PURPOSE

The aim of this study was to assess the effectiveness and safety of ultrasound guided percutaneous radiofrequency ablation (RFA) of cervical metastatic lymph nodes (LNs) from papillary thyroid carcinoma.

METHODS

54 metastatic LNs confirmed by percutaneous biopsy in 33 patients with previous total thyroidectomy and radioiodine therapy were enrolled in this retrospective study. US and contrast-enhanced ultrasound (CEUS) examinations were performed before ablation. Follow-up consisted of conventional US, CEUS, thyroglobulin (Tg) level at 1, 3, 6, and 12 months and every 6 months thereafter. In 3 months after ablation, US-guided core needle biopsy (CNB) was performed in the center, at the edge of the ablation area to exclude recurrence.

RESULTS

Technical success was obtained in all 54 lymph nodes (100%) without immediate or later major complications occurred. With a mean follow-up of 21 ± 4 months (range 12-24 months), there were no evidence of recurrence at ablated sites. After RFA, 33 metastatic LNs completely disappeared (33/54, 61.1%) and 21 metastatic lymph nodes remained as small scarlike lesions (21/54, 38.9%) at the last follow-up visit. The mean volume reduction ratio (VRR) was 32.7 ± 8.6% (range 21.2-59.3%), 46.8 ± 9.7% (range 33.6-68.1%), 62.5 ± 12.1% (range 42.5-95.4%), 77.1 ± 10.6% (range 54.3-100.0%), 89.2 ± 8.3% (range 68.7-100.0%) and 94.9 ± 5.3% (range 78.2-100.0%) at 1, 3, 6, 12, 18 and 24 months after RFA respectively. Significant differences in the VRR were found between every two follow-up visits (P < 0.001). At the last follow-up visit, the mean serum Tg level decreased from 10.2 ± 5.1 ng/ml (range 0.8-16.2 ng/ml) to 1.1 ± 0.8 ng/ml (range 0.2-3.1 ng/ml) (P < 0.001).

CONCLUSIONS

Ultrasound guided percutaneous RFA for cervical metastatic LNs from papillary thyroid carcinoma is a feasible, effective and safe therapy. This procedure shows a nonsurgical therapeutic option that can eradicate the lesions with a very low complication rate.