# Efficacy and safety of radiofrequency ablation (RFA) for recurrent metastatic thyroid carcinoma to the lateral neck: a systematic review

## TL;DR

Radiofrequency ablation (RFA) is a safe and effective treatment for thyroid cancer recurrence in the lateral neck, offering high success rates and fewer complications compared to surgery.

## Contribution

This study systematically compares RFA for lateral versus central neck recurrence, highlighting its efficacy and safety profile.

## Key findings

- RFA achieved complete nodule disappearance in up to 97% of patients with lateral neck recurrence.
- RFA had a recurrence-free survival rate of 90.8–96% at 1–3 years and up to 94.5% at 6 years.
- RFA had fewer complications than surgery, with no reported hypocalcemia and lower rates of voice changes.

## Abstract

To evaluate the efficacy and safety of radiofrequency ablation (RFA) for lateral cervical recurrence of metastatic thyroid carcinoma compared to revision surgery (after a primary thyroidectomy and selective neck dissection) and RFA in the central compartment or thyroid bed. This review focuses on studies that differentiate between lateral and central neck RFA, as lesion location might influence outcomes and complication rates.

A systematic review was conducted using the PRISMA guidelines, looking at articles that address management of thyroid cancer recurrence in the lateral neck. Data on tumor volume reduction, thyroglobulin (Tg) levels, recurrence rates, and complications were analyzed.

Eight studies were include in this review. Across 252 patients treated with RFA, complete nodule disappearance was reported in up to 97% of cases, with therapeutic success rates ranging from 92 to 100%. Volume reduction rates (VRR) reached 93–100% at 24–60 months. Thyroglobulin levels consistently decreased post-treatment, with reductions from baseline values as high as 37 ng/mL to < 1 ng/mL. Recurrence-free survival was 90.8–96% at 1–3 years, and up to 94.5% at 6 years in long-term follow-up. Radiofrequency ablation demonstrated a favorable safety profile: transient voice changes occurred in 3.7–8.6% of patients, mainly in central lesions, with no reported cases of hypocalcemia. Surgery showed higher complication rates, including hypocalcemia (8.7–30%) and permanent voice changes. Comparative studies showed that while surgery may offer more frequent biochemical remission, RFA remains effective with fewer complications.

RFA is an effective, minimally invasive alternative for lateral cervical recurrence of thyroid cancer. Its high efficacy and superior safety profile make it a valuable option, particularly for patients avoiding revision surgery. Differentiating lateral and central RFA is important, as both show comparable efficacy, though central RFA has a higher complication risk.