Radiofrequency ablation has been found to be safe and effective for the treatment of low-risk thyroid papillary microcarcinomas and is an effective alternative to surgery.
This was the conclusion of a meta-analysis of controlled trials by researchers from the Department of Surgical Oncology and Gastrointestinal Surgery, University Medical Centre Rotterdam, The Netherlands.
Thyroid cancer is the most prevalent endocrine malignancy and accounts for 3–4% of all cancers and was the ninth most common cancer in 2020. The incidence of thyroid cancer around the world has increased over the past several decades and this has been largely driven by new cases of papillary thyroid microcarcinoma cancer. In fact, papillary thyroid cancer comprises about 80–85% of thyroid malignancies.
Thyroid surgery is the most common management option for patients with papillary thyroid microcarcinoma, although in such low-risk patients, accumulated data from trials suggest that active surveillance (i.e. observation without immediate surgery) can be the first-line management for patients, although a further alternative is the use of thermal ablation techniques, which includes radiofrequency ablation as well as laser and microwave modalities.
Nevertheless, the effectiveness and safety of radiofrequency ablation for the management of patients with low-risk papillary microcarcinoma of the thyroid is largely unknown.
For the present study, the Dutch team set out to examine the safety of this particular thermal ablation modality in patients with papillary microcarcinoma and who had been treated with radiofrequency ablation for the first time. The primary outcome was the complete disappearance rate of microcarcinomas whereas secondary outcomes included tumour progression and complications.
Radiofrequency ablation and tumour complete disappearance
A review of the literature identified 15 eligible studies including with 1,770 patients (mean age = 45.4 years, 77.9% female). In these 15 studies, a total of 1,822 tumours were treated with 1,872 radiofrequency ablation sessions and all participants had papillary microcarcinomas confirmed by ultrasonography.
In 12 of the studies, data on complete disappearance of tumour tissue was reported and the mean follow-up time was 33 months, which varied between 27.8 and 91% at 12 months and between 29.3 and 100% after 34 months. The pooled complete disappearance rate at the end of the follow-up period was 79% (95% CI 65 – 94%).
For the outcome of tumour progression, the overall rate was 1.5% and residual tissue in the ablated area was found in only 7 patients and new tumour in 15 patients, with 4 patients developing lymph node metastases during follow-up although no distant metastases were observed for any patients.
Only 3 major complications occurred, two patients with voice changes lasting over two months although this change resolved and 1 cardiac arrhythmia during the radiofrequency ablation procedure. Overall, there were 45 minor complications including post-treatment pain (20 patients) and the pooled proportion of the complication rate was 2%.
The authors concluded that radiofrequency ablation is a safe an efficient method for the management of low-risk patients with microcarcinoma papillary thyroid tumours. They added how radiofrequency ablation could become a step-up treatment after local tumour growth in those with active surveillance or in low-risk patients concerned over an active surveillance approach and who wished to avoid surgery.
Citation
van Dikj SPJ et al. Assessment of Radiofrequency Ablation for Papillary Microcarcinoma of the Thyroid: A Systematic Review and Meta-analysis JAMA Otolaryngol Head Neck Surg 2022
