BACKGROUND
Thyroid nodules are common and are best characterized by neck ultrasound. Fortunately, > 90% of nodules are benign and usually don’t cause symptoms and don’t need any treatment. However, up to 10-15% of benign nodules can grow and lead to symptoms such as hoarseness, difficulty swallowing or breathing, neck pain, or lumps in the neck that can be seen. If a benign nodule becomes large enough, surgery may be needed.

Surgery, such as a total thyroidectomy or lobectomy, carries risks such as voice changes, permanent low calcium levels (hypoparathyroidism), neck scarring, and sometimes the need for lifelong thyroid hormone replacement. To reduce the need for surgery, several less invasive treatments like radiofrequency ablation (RFA) and microwave ablation (MVA) have been developed. These techniques use heat to destroy thyroid nodules, but the heat can damage surrounding structures and leave behind hard scar tissue, which can make the thyroid stiff and uncomfortable.

A newer technique, nanosecond pulsed field ablation (nsPFA), avoids heat altogether. It uses ultra-short electrical pulses to trigger a natural process called regulated cell death (apoptosis), similar to how normal cells die at the end of their life cycle. The body then clears these cells safely without burning or scarring. nsPFA has already been used for benign skin lesions with no serious complications. This study evaluated the safety and effectiveness of nsPFA for treating benign thyroid nodules.

THE FULL ARTICLE TITLE
Spiezia S, et al. First-in-human clinical feasibility study of ablation of benign thyroid nodules using nanosecond pulsed field ablation. Thyroid 2025;35(9):1024-1029.

SUMMARY OF THE STUDY
This early study involved 30 patients (23 women and 7 men) with benign thyroid nodules referred for consideration of surgery. The researchers divided them into three groups based on the treatment they received.

In the first group of five patients, the “proof-of-concept” group, patients were treated with nsPFA under general anesthesia. Then they had a lobectomy or thyroidectomy immediately after, so the researchers could examine the thyroid tissue under a microscope. The 2nd group of 20 patients had only part of their nodules treated with nsPFA in 2-4 areas using different energy settings under local anesthesia. Ultrasound scans were done weekly for a month, then at 3, 6, and 12 months. 10 of these patients were re-treated at 12 months. The 3rd group of 5 patients had their nodules fully treated with nsPFA and ultrasound was performed monthly for a year.

When researchers examined thyroid tissue from the first group, they found that nsPFA caused cell death without heat-related damage or scarring, a positive result. Patients in the second group showed some reduction in nodule size and reported symptom relief as early as 2 weeks after treatment, with no scarring typically observed after RFA. Overall 2 patients in this group experienced temporary voice hoarseness that resolved within 24 hours. No other side effects were noted.

Patients in the third group experienced the most significant improvement. Nodule size decreased by 48% at two weeks and 71% at four weeks—a level of reduction that typically takes 6 months to achieve with RFA. After 1 year, the reduction in size reached 86%. Patients recovered rapidly from the procedure, with only minor pain, swelling, or bruising that resolved within days and no visible scarring.

WHAT ARE THE IMPLICATIONS OF THIS STUDY?
The results of this study suggest that nsPFA is a safe, effective, and minimally-invasive treatment for symptomatic benign thyroid nodules. The rapid rate of nodule shrinkage without serious side effects makes this new approach promising. However, because this was a small study, more research is needed before it becomes widely available.

— Philip Segal, MD

Table of Contents | PDF File for Saving and Printing