Is Radiofrequency Ablation a Good Alternative to Surgery for Benign Thyroid Nodules? A Look at Benefits, Risks

Ultrasound-guided radiofrequency ablation (RFA), a minimally invasive alternative to thyroid surgery, has been used internationally to shrink large, benign thyroid nodules for more than a decade. But only in recent years has there been growing interest in the U.S. in this procedure, typically performed by endocrinologists, radiologists, and otolaryngologists.

“As a thyroid surgeon, I became aware of literature that arose in Asia and Europe, where radiofrequency ablation has been used for many years for the thyroid gland,” said Gregory W. Randolph, MD, a professor of otolaryngology–head and neck surgery, director of the thyroid and parathyroid endocrine surgical division, and the Claire and John Bertucci Endowed Chair in Thyroid Surgical Oncology at Harvard Medical School in Boston. “In reviewing that material, it became apparent that this is something that might be worthwhile to introduce in the United States.”

Benefits of Radiofrequency Ablation

RFA has many benefits as a nonsurgical alternative to shrinking benign thyroid nodules greater than 2 cm, according to Lisa A. Orloff, MD, director of the Endocrine Head and Neck Surgery Program and a professor in the department of otolaryngology, division of head and neck surgery, at the Stanford University School of Medicine in Stanford, Calif. Dr. Orloff’s clinical practice focuses on the surgical management of thyroid and parathyroid tumors and disorders.

One of those benefits is that there is no absolute upper limit to the size of nodule that can be treated, and success is greatest for smaller nodules that are still greater than 2 cm. “Its appeal lies largely in avoiding loss of an entire thyroid lobe for the sake of treating a nodule, and there’s no surgical scar,” said Dr. Orloff. RFA is usually an office-based procedure, done under local anesthesia, with a recovery time of one to two days. It typically takes between 20 and 40 minutes.

Hemithyroidectomy is typically recommended for treatment of a symptomatic and/or enlarging cytologically benign thyroid nodule, and this is associated with an approximately 20% to 25% chance of resultant hypothyroidism requiring thyroid hormone therapy, said David L. Steward, MD, the Helen Bernice Broidy professor and chair of the department of otolaryngology–head and neck surgery at the University of Cincinnati College of Medicine. With RFA, Dr. Steward estimates that the chance of resultant hypothyroidism drops to about 5% or less, which is a significant motivator for patients.

The minimally invasive technique, which involves the insertion of a needle into the thyroid nodule, delivering ablation energy to alter the nodule, is tolerated very well by patients, said Dr. Randolph. As the nodule heals in the ensuing months, shrinkage occurs in the treated areas. “You can get volumetric reductions of 60% to 90%,” he said, which usually results in improvement in both symptoms and any cosmetic issues the patient was experiencing.

Its appeal lies largely in avoiding loss of an entire thyroid lobe for the sake of treating a nodule, and there’s no surgical scar. —Lisa A. Orloff, MD

Patients with very large thyroid goiters need to weigh the pros and cons carefully, as they will be looking at more than one procedure over time to cause adequate shrinkage, said Catherine F. Sinclair, MD, a dual fellowship-trained neck and thyroid surgeon and laryngologist. Based in Melbourne, Australia, Dr. Sinclair completed fellowships in the United States and worked for nearly a decade at Mount Sinai in New York City as an associate professor and director of head and neck surgery at Mount Sinai West.

“Baseline nodule volumes greater than 20 cc have been shown to be more likely to require a second procedure,” she said. “Similarly, patients with significant retrosternal extension of a nodule will likely require multiple procedures, as a single procedure won’t significantly address the retrosternal component—a single procedure can be used to cause contraction of the upper part of such a nodule and thus pull the retrosternal component upward into the neck so that it can be ablated in a delayed fashion.”

Risks of the Procedure

Kathleen E. Hands, MD, an endocrinologist in San Antonio, Texas, who specializes in thyroid and parathyroid disorders, said she has had patients who present with 4- to 12-cm nodules. Dr. Hands said she has performed the procedure more than 50 times since November 2019, when she became the first female endocrinologist to perform it.

“Being able to explain the risks to patients and knowing when to refer them to surgery is vital,” she said. “A 6-cm nodule likely requires two procedures, but a 4-cm nodule compressing the trachea significantly may need to go to surgery. The entire neck needs to be assessed, including the airway and the great vessels. If the airway is so compromised that any swelling may cause loss of airway, they aren’t safe to do RFA as an outpatient,” Dr. Hands said.

Patients who have nodules with indeterminate biopsy results (Bethesda 3 or 4) are also not good candidates for ablation due to a heightened risk of malignancy in these nodules, said Dr. Sinclair. Similarly, thyroid cancers larger than 1.5 cm are poor candidates; surgery is a better option as long as the patient can tolerate surgery.

Other patients who may not be good candidates are those with needle phobias who may struggle with the procedure being performed under local anesthesia and may require sedation for adequate ablation. Patients with bleeding disorders need to be carefully assessed regarding their risk from the procedure. And Dr. Sinclair said that patients with Graves’ disease aren’t good candidates for ablation if their goal is to cure the hyperthyroidism in addition to shrinking any nodules. “Hyperthyroidism is caused by systemic antibodies that ablation alone will not combat,” she said.

Substernal goiters may not be accessible, added Dr. Orloff, and patients who don’t tolerate neck extension aren’t ideal. Additionally, if a patient has Hashimoto’s thyroiditis and already requires hormone replacement, they may have less incentive to keep their thyroid lobe or lobes, although this is not a contraindication.

With biopsied, indeterminate, or suspicious nodules, Dr. Steward prefers to resect or wait and see.

Potential complications from the procedure include injury to the recurrent laryngeal nerve (RLN) and, on rare occasions, the vagus nerve in the carotid sheath, the sympathetic chain posterior to the carotid artery, the brachial plexus in the supraclavicular fossa, and the phrenic nerve on the deep neck musculature (Head Neck. 2022;44:633-660).

Being able to explain the risks to patients and knowing when to refer them to surgery is vital. A 6-cm nodule likely requires two procedures, but a 4-cm nodule compressing the trachea significantly may need to go to surgery. —Kathleen E. Hands, MD

The most frequent complication after RFA is voice change. A systematic review and meta-analysis conducted by Chung et al. (Int J Hyperthermia. 2017;33:1-35) identified a 1.44% overall rate of transient or permanent voice change following RFA based on subjective voice assessment. The rate of voice change was higher (7.95%) in the subset of 176 patients undergoing RFA for recurrent thyroid cancer, primarily in the central compartment. Injection of cold irrigant in the region of suspected thermal injury when voice change develops has been proposed as a management strategy for mitigating RLN injury (Int J Hyperthermia. 2019;36:204-210), although prior studies have reported hypothermic nerve damage with exposure to cold solutions (Head Neck. 2022;44:633-660).

The next most recent complication of RFA is thyroid nodule rupture. Neck swelling typically appears two to four weeks following the procedure (Head Neck. 2022;44:633-660).

Best Practices and Training

In December 2021, an international interdisciplinary consortium of medical societies, including the American Head and Neck Society (AHNS) Endocrine Surgery Section, published a multiconsensus statement on best practices in the use of RFA (Head Neck. 2022;44:633-660). The statement’s recommendations for best practices included:

• Ultrasound (US)-guided ablation procedures may be used as a first-line alternative to surgery for patients with benign thyroid nodules contributing to compressive and/or cosmetic symptoms.
• Although less efficacious than surgery or radioactive iodine in normalizing thyroid function, thermal ablation procedures can be a safe therapeutic alternative in patients with an autonomously functional thyroid nodule and contraindications to first-line techniques.
• US-guided ablation procedures may be considered in patients with suitable primary papillary microcarcinoma who are unfit for surgery or who decline surgery or active surveillance.
• Prior to performing any US-guided thermal ablation procedure, advanced training in and facility with US of the thyroid and neck are essential.
• Proficiency with US-guided fine needle aspiration biopsies of thyroid nodules is recommended for performance of US-guided ablation procedures.
• The provider should receive specific instruction on the chosen ablation technique, with the opportunity to practice on a phantom model and to observe cases.
• Optimal practice involves one’s initial cases being supervised by a physician experienced in US-guided ablation procedures.
• Using the moving shot technique via the trans-isthmic approach and delivering energy only when the needle tip is visualized by US is paramount to effective ablation in the performance of RFA.

Proper training in RFA is essential for patient safety. Dr. Orloff said the landmark courses are in Korea, Brazil, and Italy, where her international colleagues have vast experience and expertise, having been the true pioneers in the thyroid RFA procedure. While COVID-19 put a damper on progress in RFA education and training, courses are beginning to be offered in the United States. She said didactic learning and case-based discussions are available through multiple online offerings, including the AHNS Endocrine Surgery Section, the World Congress on Thyroid Cancer, vendor- sponsored webinars, and institutional courses, but that hands-on learning is essential before undertaking the procedure.

“The best form of hands-on simulation training available is through cadavers,” said Dr. Hands. “Courses are offered all over the country. Unfortunately, universities are seemingly last on board, not wanting to invest in the process and waiting for Medicare codes for billing, which may take another two years.”

She noted that RGS Healthcare is the support system she uses; she also proctors for them. “They provide excellent hands-on experience to include cadaver training,” she said. Dr. Hands has proctored several courses with more than 30 physicians, including radiologists, surgeons, and endocrinologists, and she has mentored close to 15 surgeons and endocrinologists in her office and on site at clinicians’ offices.

As RFA becomes more popular in the United States, physicians who perform the procedure are increasingly seeing patients who read about RFA online and seek a consultation. “Patients want to keep their thyroid function and don’t want to go to surgery,” said Dr. Hands. “They come from other countries and all over the U.S.”

Talking to Patients

According to Dr. Randolph, the benign nodule diagnosis should be discussed thoroughly with the patient so he or she understands what it is, along with all appropriate options, including following the nodule over time to see whether it’s stable or growing; performing surgery, which removes the nodule permanently; and RFA, which gives candidate patients the ability to have the nodule reduced in size with no incision, under a local anesthetic. RFA can be repeated if needed.

“Radiofrequency should be described as an option, along with other existing options, to patients,” he said. While he doesn’t prefer one procedure over another, he does skew a bit more toward recommending surgery to younger patients with very large nodules, because these patients have many years ahead of them. “If the nodule is large and the patient is young, that means the nodule is quite aggressive in its growth,” he said.

Dr. Sinclair said that whether a physician offers RFA as part of their practice or not, being informed about all options available for a given disease is a physician’s ethical and professional responsibility to their patients. “They should be willing to refer to a colleague who does when appropriate,” she said.

Because not all patient and thyroid nodule anatomy is suited for RFA, however, Dr. Orloff said that determination of candidacy and proper selection are best achieved by a physician with US and RFA experience.

When patients ask Dr. Randolph what RFA is like, he tells them they already know because it’s quite similar to the US-guided needle biopsy they just had. (Every patient who has RFA has already had a needle biopsy.) “You could have a little discomfort, generally, but we give people an ice pack for a few minutes and a bandage whether they had a needle biopsy or the ultrasound-guided radiofrequency ablation,” he said.

Dr. Steward said that, in his experience, the procedure for patients is analogous to the US-guided needle biopsy, but more invasive, causing more localized discomfort when the thermal energy is delivered. “It takes it up a notch and generally requires more extensive local anesthesia,” he said, adding that sometimes patients can hear it crack or sizzle and feel warmth. Afterward, there may be localized swelling, edema, or bruising.

Equipment Requirements

The basic equipment needed for RFA includes the radiofrequency generator (power source, with pump for circulating cooling fluid), grounding pads, single-use electrodes specifically designed for thyroid application, and an ultrasound machine with an ultrasound probe. There are currently two U.S. commercial vendors, both of which supply equipment that’s manufactured in Korea, according to Dr. Orloff.

I think if it’s going to be offered, it’s important that patients understand that they may have to pay out of pocket. —David L. Steward, MD

“The electrode comes in different active tip sizes—5, 7, and 10 mm—with choice of tip size dependent on size and location of the nodule to be treated,” said Dr. Sinclair. “In addition to these basics, I also use local anesthesia, syringes, needles, skin prep, drapes, and sterile ultrasound covers.”

According to the AHNS report, smaller electrodes are used for nodules in high-risk locations or beside critical structures and those that require a high degree of control in the treatment area. For nodules greater than 4 cm, using the 10-mm electrode reduces ablation time. These different electrode sizes are available in a single device.

The majority of thyroid RFA cases use monopolar electrodes, but bipolar electrodes, in which current passes between the electrodes at only the tip of the device and deliver more focused energy, are also available. There is some evidence that these more focused devices may be safer for use in pregnant patients or those with implanted cardiac electrical devices. While not yet FDA approved, these electrodes are used clinically in Europe and Asia. Innovations such as unidirectional ablation electrodes insulated in a way that creates a narrower ablation and virtual needle tracking systems have also been developed to make monitoring the electrode tip easier and may benefit clinicians learning the RFA technique (Head Neck. 2022;44:633-660).

Treatment Reimbursement

The main drawback when it comes to RFA is that it’s considered new technology, and, in many cases, insurance does not reimburse for it.

“I think if it’s going to be offered, it’s important that patients understand that they may have to pay out of pocket,” Dr. Steward said. “Patients who are seeking RFA may already be aware of this issue, but many are often not.” He added that patients also need to know that the procedure doesn’t completely remove the nodule, so they could need another RFA treatment and the remnant nodule may not appear as benign on subsequent US examination.

Many of Dr. Hands’ patients, she said, are now getting reimbursed for some portion of their procedure, even though they may initially be denied. “We provide them with an appeal letter that usually does the trick,” she said. “Some are approved before we even do the procedure.”

While reimbursement policies differ from state to state, Dr. Hands said that even some of her Medicare patients have been reimbursed. “A clinical note is vital to reimbursement, and documenting patient symptoms helps on the review process,” she said.

Is it worth investing in the training and equipment for doctors who are considering offering RFA? “It depends on how many of the procedures they do,” said Dr. Steward. “If you’re paid $5,000 cash for 50 patients a year, that’s a lot of money to cover the costs. If you do a couple patients and try to get the insurance company to reimburse, it’s probably not worth it financially at this time. This is a new tool for a select subset of patients with symptomatic, cytologically benign, large or enlarging thyroid nodules, as an alternative to traditional surgery. The coding and reimbursement has yet to catch up.”

Dr. Steward explained that Category III CPT codes are typically designed for new technology like RFA. A new Category III T code became available for laser ablation of thyroid nodules in January 2022, but it’s unclear if this would apply to radiofrequency ablation, otherwise performed as an unlisted code. “There’s an extensive process of new technology going from initial adopters to being commonplace,” he said. “I think it will take a few years before RFA is a common procedure that’s widely available, but as soon as insurance reimburses for it, it will become widely available.”

While offering RFA for benign thyroid nodules hasn’t yet paid off from a practice perspective for Dr. Steward, he said it has paid off in terms of benefit to an individual patient. Dr. Hand noted that the patients she has treated with RFA found her online, knew the costs, and wanted to avoid surgery so badly that none of them “batted an eye.” She’s currently overwhelmed with requests for the procedure.

Patient testimonials on Dr. Hand’s Facebook page (https://www.facebook.com/RadiofrequencyRFA) share stories and images that include a 75% reduction in nodule size three months post treatment with RFA with no loss of thyroid function and full resolution of cosmetic concerns. She also posts You- Tube interviews on the page to educate prospective patients with thyroid nodules about RFA.

“I was really surprised at the volume I was doing last year, but this speaks to how much patients wanted to avoid surgery,” she said. “They’re coming to me from thousands of miles away. I believe that, in the future, thyroid specialists who aren’t offering this may want to reconsider now. The last ones trained have the least amount of experience and will get the fewest referrals.”

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Renée Bacher is a freelance medical writer based in Louisiana.