Ultrasound-guided radiofrequency ablation (RFA) is a minimally invasive nonsurgical procedure that has been used for decades to treat benign and malignant tumors of the liver, bone, kidney and lung as well as aberrant conduction pathways of the heart (1-7). Internationally, RFA has been shown to be safe and effective for treating thyroid conditions which include symptomatic benign thyroid nodules, as well as primary and recurrent thyroid cancer (8-17). In North America, surgery is the standard of care for removal of thyroid malignancy and the evidence for success of RFA in this population is limited. However, when we look at the success and ease of RFA treatment demonstrated among international circles, this treatment modality is a promising alternative to surgery for patients who pose risk due to their multiple medical comorbidities or those otherwise motivated to minimize the risks of treatment and the time of recovery.
RFA eliminates the need for an incision, removal of the thyroid as well as a general anesthetic, making this an attractive option for patients who pose surgical risk. With the use of local anesthetic or light sedation, the needle probe can be inserted into the midline of the anterior neck at the level of the isthmus, using ultrasound guidance, to avoid injuring nearby structures. Knowledge of the anatomy of the neck is essential for safety and is associated with low complication rate when performed by an experienced operator, surgeon or radiologist with ultrasound guidance. Because it does not require general anesthesia and can be completed in the office setting, there are other potential advantages even for patients who are not interested in the traditional surgical approach.
Herein, we review this novel nonsurgical approach, and the role RFA may play in expanding the treatment options for benign (non-secreting and secreting nodules) as well as primary or recurrent malignant tumors of the thyroid in patient’s ineligible for surgery.
Internationally, RFA is established as a safe and effective method for treating benign thyroid nodules (8,11-13,18-30). Enlarged thyroid nodules may cause compressive symptoms, globus sensation, and distortion or asymmetry of the neck, prompting patients to seek treatment. Traditionally, surgery has been the definitive treatment, but a cervical scar, potential hypothyroidism and a general anesthetic may be undesirable for some patients with a benign condition. RFA provides a minimally invasive, low risk procedure for reducing pressure symptoms while avoiding the need for a mid-cervical scar.
The international literature supports RFA as an effective method for relieving compressive symptoms for benign nodules (18,19,31-35). Over time, RFA can reduce the size of a nodule by 33–58% after one month, by 51–85% after 6 months, and by 93% after 4 years (28,36). Worldwide, RFA is one of the more common ablative procedures that utilizes thermal energy, for reducing the volume of predominantly benign solid nodules (35,37). However, in long-term follow up, Lim et al. demonstrated a well-maintained volume reduction in size of over 93% in benign nodules regardless of whether they were cystic or solid (28). A recent study by Bernardi et al. demonstrated a significant sustained reduction in the nodule volume (85%) after 5 years post-treatment (35). The “moving shot” technique with a heated electrode may explain why RFA is effective: the tumor margins may be included in the ablation after protecting surrounding critical structures with an aqueous buffer, thereby maximizing the surface area the electrode reaches and preventing marginal regrowth (28,37).
For benign non-secreting nodules causing pressure or compression on the trachea, surgery is definitive. However, RFA has not been shown to be inferior to the surgical option and effectively reduces nodule volume. In a meta-analysis, Trimboli et al. demonstrate a significant reduction in the volume of RFA treated nodules, compressive symptoms and cosmetic scores with sustained nodule reduction for up to 2–3 years in nodules smaller than 30 mL (38). Bernardi et al. demonstrated a significantly reduced nodule volume for up to 5 years post treatment that was maintained in 85% of RFA treated patients with a benign nodule with only 12% requiring retreatment (35). Generally, RFA has the best reduction rates for smaller nodules (volume <10 mL), with success for up to 2 years (23,28,29,38-41). Lim et al. is one of many to demonstrate that larger nodules (>20 mL) require repeat RFA treatment compared with smaller nodules in order to achieve a similar volume reduction during a 4-year follow up (28). A consensus regarding the definition of small, medium and large nodules is still lacking, including the number of RFA sessions required to achieve desired results (42).
Sensory nerves present around the thyroid capsule are anesthetized with lidocaine injection. Different techniques have been described for nodule ablation; the Korean Guidelines, the Italian society and the Italian working group on Minimally Invasive Treatments of the Thyroid (MITT), the European thyroid association clinical guidelines, as well as the Austrian society recommend using the “moving shot” technique once the probe has advanced into the thyroid nodule (18,19,31-33,43). The probe introduces a high-frequency alternating current that causes localized coagulative necrosis and cell death through high temperatures of 60 to 100 degrees Celsius (44). As a result, slowly and over time, the nodule reduces in size. Sustained nodule reduction has been achieved along with reduced complications and recovery time compared to surgery (22,23). Furthermore, the “moving shot” technique (trans-isthmic approach) has been shown to minimize potential thermal injury to the recurrent laryngeal nerve (13).
Almost a decade ago, the Korean Guidelines published strong evidence that RFA is a safe, well tolerated procedure with a low incidence of complications (1,8,13,18,19,45-48). Over time, various international societies have produced additional guidelines which endorse RFA as a safe and effective treatment for benign nodules. These guidelines include the Korean society of thyroid radiology, the Italian Working Group on Minimally Invasive Treatments of the Thyroid (MITT), the European Thyroid Association Clinical Practice Guidelines, the United Kingdom’s National Institute for Health and Clinical Excellence (NICE), as well as the Austrian thyroid association (18,19,31-34,43). The international societies all agree that RFA is safe for benign symptomatic nodules or cosmetic concerns once the nodule is confirmed to be cytopathologically benign on at least two FNA or core biopsies (18,19,31-33,49).
For treatment of benign nodules, the overall complication rate is 2.11% [95% confidence interval (95% CI): 1.15–3.06], whereas the overall complication rate for recurrent thyroid cancers is higher at 10.98% (95% CI: 4.82–17.15) (13). No life- threatening complications are reported, and minor complications include pain, skin burn, and hematoma (19). The most common major complication noted is voice change, with an incidence of 0.94% for benign nodules, and an exceedingly low incidence of permanent changes (13). Nodule rupture is the second most common major complication after RFA treatment (0.17%, 4/2421) (13). Patients may present with sudden neck bulging and pain at the RFA site due to delayed hemorrhage, however the incidence remains low. Additionally, different trials reported the most common complication was temporary pain (10,20,50,51).
Generally, one treatment with RFA maintains effective volume reduction (11,12), however other studies have shown with follow-up longer than 3 years, more than two session of RFA may be necessary to maintain long-term volume reduction (12,28,39). Larger nodules (>20 mL) are more likely to require two sessions of RFA instead of the one treatment that has successfully ablated smaller nodules (40). Studies have demonstrated that RFA reduces nodule volume, relieves local symptoms and cosmetic concerns as effectively as thyroid lobectomy (22,23).
Autonomously functioning tumors
The American Thyroid Association (ATA) Guidelines outline that surgery or radioactive iodine (RAI) treatment is effective for the treatment of autonomously functioning thyroid nodules (AFTN) (52,53). These two options are not always acceptable for patients since RAI involves receiving radiation which is controversial in women of childbearing age (53). Both treatments have potential complications such as hypothyroidism. Even with lobectomy, surgery confers roughly a 30% chance of hypothyroidism, which is generally avoided in RFA-treated patients (54,55). RFA may gain favor with patients wishing to avoid developing post-operative hypothyroidism (10,20,23,50,56,57).
Many trials have demonstrated efficacy and safety of treating AFTN with RFA (10,20,23,50,56,57). However, compared with benign non-secreting nodules, the volume reduction and normalization of thyroid function in AFTN tends to be more variable (50,57). An important factor that can affect whether euthyroidism is achieved post RFA is the nodule size. When the pretreatment volume of the AFTN is small and homogeneous, the outcome tends to be more consistent. Cesareo et al. compared the reduction between medium sized nodules (18 mL) versus smaller sized nodules (5 mL), and found that euthyroidism was achieved 86% in small nodules versus 45% in medium size nodules (58). Similarly, Cappelli et al. report a volume reduction rate of 73% with TSH normalization in 94% of patients treated with RFA with nodules an average of 7 mL (59). After one session of RFA, Cervelli et al. demonstrated a volume reduction rate of 76% with a 91% TSH normalization at 12-month follow up in AFTN that were homogenous in volume and pretreatment size (60). However, in a systematic review, Cesareo et al. found only modest results with TSH normalization post RFA treatment (61). Further work done by Cesareo et al. found that when the volume of a nodule was reduced by >80%, the greater the chance of thyroid function normalization and symptoms resolution (58,61). Due to the variability in results with AFTN, all guidelines take a more cautious tone when recommending RFA as curative for AFTN (19,31,32-34,43).
Other large multicenter trials and systematic reviews provide promising results for the treatment of AFTN with RFA. Sung et al. demonstrated improved symptoms of hyperthyroidism along with normalized TSH levels in 81.8% of study patients without the development of hypothyroidism post RFA (56). In a systematic review, more than 50% of patients after RFA could discontinue their anti-hyperthyroid medications after RFA (32,42). Additionally, patients that received RFA found significant improvement in their compressive symptoms due to the reduced nodule volume (mean volume reduction ratio, 81.7% during the mean follow-up period of 19.9 months). No major complications were reported in this trial (32,42). Progression of hypothyroidism, if any, after treatment may be better explained by the progression of autoimmune thyroiditis associated with preexisting thyroid antibodies.
The Korean Guidelines and various authors suggest that follow up post RFA should be based on ultrasonographic features and TSH of the AFTN (19,56,57). This will determine whether the patient’s anti-thyroidal medications can be stopped or if they require another treatment with RFA. Previous studies report a mean number of RFA treatment sessions to be 1.8–2.2 (1–6 sessions) for AFTN (20,62). Previous reports show that single session RFA allowed withdrawal of ATD in 22–50% of patients (50,57). Further, the dose of methimazole was reduced after RFA in 78% of patients (50). The improvement in thyroid function is seen over time after RFA treatment, with 50% remission 12 months after the procedure (57). While RFA for benign nodules is certainly effective and beneficial for most symptomatic patients, the results of RFA for AFTN are more variable.
Papillary thyroid cancer, the most common subtype of thyroid cancer has an excellent prognosis once treated surgically (52). For primary thyroid cancer, surgery is the standard of care, followed by RAI and thyroid replacement therapy (52). Contrary to “one size fits all” approach where all patients presenting with thyroid cancer receive total thyroidectomy, the recent ATA guidelines have recommended thyroid lobectomy or even active surveillance for low-risk cancers (52). This paradigm shift in patient care is supported by large international trials that demonstrate the indolence of papillary thyroid cancer (63,64). This point of departure from the traditional approach is where RFA may be best suited.
In international circles, patients with primary low risk thyroid cancer are offered active surveillance of low-risk thyroid cancer or RFA as an alternative if they are ineligible for surgery (65). The indications for RFA in primary tumors have not been clearly established. Alternative treatments are reserved for patients that clinically require treatment but are too high risk to have repeat surgery, or who refuse surgery (52). Although, the data in North America for this treatment is limited, the Korean Guidelines have provided sound evidence that prove the safety and long-term efficacy of treating low risk papillary thyroid microcarcinomas (PTMC) with success (16,17,65-68). Additionally, for patients that are ineligible for surgery, Kim et al. demonstrated a significant mean volume reduction (98.5%±3.3%) with a disappearance rate of 66.7% of primary low risk papillary thyroid cancer during 4 years of follow up (66). The international societies are divided on the use of RFA for primary thyroid cancer, such as papillary and follicular cancer (32). RFA may provide a promising therapeutic option for primary papillary microcarcinoma provided there is no multifocality or nodal metastasis present (32).
Zhang et al. demonstrated favorable oncological outcomes in the long term follow up (5 years) for patients treated with RFA for low risk PTMC (65). In their comparison of patients treated with RFA versus surgery, they found a higher quality of life, fewer complications and decreased cost was associated with the RFA treated group. Although papillary thyroid cancer tends to be indolent regardless of the strategy implemented, patients wishing to have treatment without the risks of surgery can undergo RFA safely in very select patients with oncological effectiveness (65).
RFA is effective for treating of papillary thyroid cancer, however more aggressive carcinomas such as anaplastic or medullary have shown mixed results (69,70). Jeong et al. demonstrated that RFA reduces tumor size in patients with well differentiated thyroid cancer regardless of whether the tumor is micro- or macro-carcinoma (69). However, when the histology is anaplastic (poorly differentiated), several RFA treatments are required with only minimal improvement in compressive symptoms, likely due to the rapid doubling time of this cancer (69). Thus, RFA is not accepted as primary treatment for aggressive cancers and may be used in palliative situations when all other treatments are exhausted.
Follicular neoplasm, which accounts for 10–20% of malignant thyroid nodules, is best treated with surgery, according to ATA, and and the various international guidelines (19,31,32-34,52). Often, a diagnostic dilemma exists when diagnosing follicular cancer due to the low sensitivity of FNA (71). In order to make a definitive diagnosis of follicular carcinoma, surgical resection is required to detect vascular or capsular invasion (72). For patient’s ineligible for surgery, alternatives like RFA are a possibility, however currently, there is a paucity of literature to support this practice. Ha et al. reported promising results for patients with follicular neoplasms less than 2 cm (73). Over a 5-year follow up, 8/10 follicular neoplasms disappeared, 2/10 patients had more than 97% volume reduction, and none of the patients developed recurrences or distant metastatic disease (73). Currently, many of the international societies do not support RFA for the treatment of a follicular neoplasm.
Dobrinja et al. have recommended that RFA is not used as first-line treatment for follicular neoplasm since it is unknown whether the heat from this modality may promote tumor progression and potentially delay surgery (74). Up to date, there has been no evidence to show that RFA may promote tumor progression. In a 2-year follow-up, patients with benign thyroid lesions had significant reduction in volume post RFA procedure, however in 2/6 patients with follicular neoplasm, with a Bethesda-3 or -4 and a tumor larger than 2 cm regrew after RFA and required surgery (74). It remains questionable whether there was a pre-existing undetected malignancy prior to RFA or whether the size of the treated tumor (>2 cm) played a role. The role of RFA for treating small thyroid malignancies remains to be fully elucidated but may be valuable for those who would otherwise be offered observation due to comorbidities or desire to avoid surgical intervention (e.g., PTMC).
Even though the mortality rate for well differentiated thyroid cancer is less than 1%, recurrences can occur in up to 20% and 59% of patients with low- and high-risk papillary thyroid cancer, respectively (75). Surgical removal is the treatment of choice for locoregionally recurrent thyroid cancer and can improve long term survival (52). However, prior surgery is complicated by scar tissue and undefined tissue planes which can make identification of important structures like the parathyroid glands or the recurrent laryngeal nerve more difficult and potentially risky (76). RFA may be a suitable nonsurgical option for curative or palliative purposes in patients with recurrent thyroid cancer who carry high surgical risk or refuse surgery but clinically need treatment (19).
Various studies have demonstrated that RFA can be used for curative purposes in recurrent thyroid cancer smaller than 2 cm (14,15,77). Kim et al. found a disappearance rate of 86% and a low recurrence rate of 11.5% after 3 years of follow up in the RFA group which was similar to the re-operative group (15). When compared with the surgical group undergoing reoperation, the RFA group had fewer complications including vocal cord paralysis and hypocalcemia, demonstrating the safety of this alternative treatment (15). Similarly, Lim et al. found that RFA was safe and effective for controlling recurrent papillary thyroid cancer with a 95% volume reduction, as well as a complete disappearance of 82% of the treated tumors, and a significantly decreased serum thyroglobulin level post treatment (14). Additionally, two meta-analyses support ultrasound guided RFA as an effective and safe nonsurgical option for treatment of locally recurrent thyroid cancer (78,79). The therapeutic success rate is 89.5–100%, with a volume reduction rate of >50%, and complete resolution of 68.8% of lesions treated with RFA (78,79). Longer term effectiveness and safety of RFA (>5 years) for locally recurrent thyroid cancer has also been demonstrated, with complete disappearance of 91.3% treated tumors, a 99.5% volume reduction, and significantly decreased serum thyroglobulin levels (80).
In patients with inoperable recurrent thyroid cancer, RFA can be used to provide symptomatic relief due to volume reduction (19). Given the indolent nature of differentiated thyroid cancer, surgery may be too aggressive for patients at risk for recurrent laryngeal nerve palsy, hypoparathyroidism, or spinal accessory nerve palsy. Radiation treatment may benefit high risk patients but leaves patients with side effects that can be worse than the disease itself. RAI is not helpful for eradicating gross disease but can be combined with surgery and radiation for potential benefit. RFA is a safe alternative which has the potential to be combined with other therapies for palliative intent. Symptoms of dysphagia and hoarseness may be more difficult to relieve, however Park et al. reported 63.6% of patients experienced improvement in their symptoms of neck discomfort from their bulky tumor compressing the trachea post RFA (81). Lesions that are superficially localized are more effectively treated with RFA than deeper lesions that encase the carotid artery, the recurrent laryngeal nerve or esophagus (81). For the carefully selected recurrent carcinoma, RFA may provide some control without significantly increasing the risk profile.
The current ATA guidelines recommend surgery as the first line of treatment for benign symptomatic tumors, as well as primary and recurrent thyroid cancer. However, in select patients who do not wish to undergo the risks of surgery and a general anesthetic, RFA can be performed in an outpatient clinic with local anesthesia easily, repeatedly and safely. As we continue to accumulate evidence for RFA in the Western Hemisphere and internationally, we anticipate RFA will expand our clinical tools for treating patients and be offered to patients who prefer to avoid surgery.
Provenance and Peer Review: This article was commissioned by the Guest Editors (Marcin Barczyński and Maurizio Iacobone) for the series “Recent Challenges in the Management of Thyroid Tumors” published in Annals of Thyroid. The article has undergone external peer review.
Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/aot-20-50). The series “Recent Challenges in the Management of Thyroid Tumors” was commissioned by the editorial office without any funding or sponsorship. Dr. JOR reports personal fees from Baxter Scientific, outside the submitted work. Dr. RPT reports personal fees from RGS Healthcare, personal fees from Medtronic, outside the submitted work. The authors have no other conflicts of interest to declare.
Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.
- Mauri G, Cova L, Monaco CG, et al. Benign thyroid nodules treatment using percutaneous laser ablation (PLA) and radiofrequency ablation (RFA). Int J Hyperthermia 2017;33:295-9. [Crossref] [PubMed]
- Gazelle GS, Goldberg SN, Solbiati L, et al. Tumor ablation with radio-frequency energy. Radiology 2000;217:633-46. [Crossref] [PubMed]
- Dupuy DE, Monchik JM, Decrea C, et al. Radiofrequency ablation of regional recurrence from well-differentiated thyroid malignancy. Surgery 2001;130:971-7. [Crossref] [PubMed]
- Hall WH, McGahan JP, Link DP, et al. Combined embolization and percutaneous radiofrequency ablation of a solid renal tumor. AJR Am J Roentgenol 2000;174:1592-4. [Crossref] [PubMed]
- Steinke K. Radiofrequency ablation of pulmonary tumours: current status. Cancer Imaging 2008;8:27-35. [Crossref] [PubMed]
- Rosenthal DJ, Hornicek FJ, Wolfe MW, et al. Percutaneous radiofrequency coagulation of osteoid osteoma compared with operative treatment. J Bone Joint Surg Am 1998;80:815-21.
- Sousa J, el‐Atassi R, Rosenheck S, et al. Radiofrequency catheter ablation of the atrioventricular junction from the left ventricle. Circulation 1991;84:567-71. [Crossref] [PubMed]
- Jung SL, Baek JH, Lee JH, et al. Efficacy and safety of radiofrequency ablation for benign thyroid nodules: a prospective multicenter study. Korean J Radiol 2018;19:167-74. [Crossref] [PubMed]
- Baek JH, Kim YS, Lee D, et al. Benign predominantly solid thyroid nodules: prospective study of efficacy of sonographically guided radiofrequency ablation versus control condition. AJR Am J Roentgenol 2010;194:1137-42. [Crossref] [PubMed]
- Spiezia S, Garberoglio R, Milone F, et al. Thyroid nodules and related symptoms are stably controlled two years after radiofrequency thermal ablation. Thyroid 2009;19:219-25. [Crossref] [PubMed]
- Kim YS, Rhim H, Tae K, et al. Radiofrequency ablation of benign cold thyroid nodules: initial clinical experience. Thyroid 2006;16:361-7. [Crossref] [PubMed]
- Jeong WK, Baek JH, Rhim H, et al. Radiofrequency ablation of benign thyroid nodules: safety and imaging follow-up in 236 patients. Eur Radiol 2008;18:1244-50. [Crossref] [PubMed]
- Chung SR, Suh CH, Baek JH, et al. Safety of radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: a systematic review and meta-analysis. Int J Hyperthermia 2017;33:920-30. [PubMed]
- Lim HK, Baek JH, Lee JH, et al. Efficacy and safety of radiofrequency ablation for treating locoregional recurrence from papillary thyroid cancer. Eur Radiol 2015;25:163-70. [Crossref] [PubMed]
- Kim JH, Yoo WS, Park YJ, et al. Efficacy and safety of radiofrequency ablation for treatment of locally recurrent thyroid cancers smaller than 2 cm. Radiology. 2015;276:909-18. [Crossref] [PubMed]
- Zhang M, Luo Y, Zhang Y, et al. Efficacy and safety of ultrasound-guided radiofrequency ablation for treating low-risk papillary thyroid microcarcinoma: a prospective study. Thyroid 2016;26:1581-7. [Crossref] [PubMed]
- Lim HK, Baek SM, Baek JH. US-guided RFA for primary thyroid cancer: efficacy and safety of long-term follow-up in a large population. CIRSE (Cardiovascular and Interventional Radiological Society of Europe) 2017;September;16-20.
- Na DG, Lee JH, Jung SL, et al. Korean Society of Thyroid Radiology (KSThR); Korean Society of Radiology. Radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: consensus statement and recommendations. Korean J Radiol 2012;13:117-25. [Crossref] [PubMed]
- Kim JH, Baek JH, Hyun KL, et al. 2017 Thyroid Radiofrequency Ablation Guideline: Korean Society of Thyroid Radiology. Korean J Radiol 2018;19:632-55. [Crossref] [PubMed]
- Baek JH, Jeong HJ, Kim YS, et al. Radiofrequency ablation for an autonomously functioning thyroid nodule. Thyroid 2008;18:675-6. [Crossref] [PubMed]
- Baek JH, Lee JH, Valcavi R, et al. Thermal ablation for benign thyroid nodules: radiofrequency and laser. Korean J Radiol 2011;12:525-40. [Crossref] [PubMed]
- Bernardi S, Dobrinja C, Fabris B, et al. Radiofrequency ablation compared to surgery for the treatment of benign thyroid nodules. Int J Endocrinol 2014;2014:934595. [Crossref] [PubMed]
- Che Y, Jin S, Shi C, et al. Treatment of benign thyroid nodules: comparison of surgery with radiofrequency ablation. AJNR Am J Neuroradiol 2015;36:1321-5. [Crossref] [PubMed]
- Ugurlu MU, Uprak K, Akpinar IN, et al. Radiofrequency ablation of benign symptomatic thyroid nodules: prospective safety and efficacy study. World J Surg 2015;39:961-8. [Crossref] [PubMed]
- Ahn HS, Kim SJ, Park SH, et al. Radiofrequency ablation of benign thyroid nodules: evaluation of the treatment efficacy using ultrasonography. Ultrasonography 2016;35:244-52. [Crossref] [PubMed]
- Ji Hong M, Baek JH, Choi YJ, et al. Radiofrequency ablation is a thyroid function-preserving treatment for patients with bilateral benign thyroid nodules. J Vasc Interv Radiol 2015;26:55-61. [Crossref] [PubMed]
- Huh JY, Baek JH, Choi H, et al. Symptomatic benign thyroid nodules: efficacy of additional radiofrequency ablation treatment session - prospective randomized study. Radiology 2012;263:909-16. [Crossref] [PubMed]
- Lim HK, Lee JH, Ha EJ, et al. Radiofrequency ablation of benign non-functioning thyroid nodules: 4-year follow-up results for 111 patients. Eur Radiol 2013;23:1044-9. [Crossref] [PubMed]
- Cesareo R, Pasqualini V, Simeoni C, et al. Prospective study of effectiveness of ultrasound-guided radiofrequency ablation versus control group in patients affected by benign thyroid nodules. J Clin Endocrinol Metab 2015;100:460-6. [Crossref] [PubMed]
- Aysan E, Idiz UO, Akbulut H, et al. Single-session radiofrequency ablation on benign thyroid nodules: a prospective single center study: radiofrequency ablation on thyroid. Langenbecks Arch Surg 2016;401:357-63. [Crossref] [PubMed]
- Papini E, Pacella CM, Solbiati LA, et al. Minimally-invasive treatments for benign thyroid nodules: a Delphi-based consensus statement from the Italian minimally- invasive treatments of the thyroid (MITT) group. Int J Hyperthermia 2019;36:376-82. [Crossref] [PubMed]
- Garberoglio R, Aliberti C, Appetecchia M, et al. Radiofrequency ablation for thyroid nodules: which indications? The first Italian opinion statement. J Ultrasound 2015;18:423-30. [Crossref] [PubMed]
- Dobnig H, Zechmann W, Hermann M, et al. Radiofrequency ablation of thyroid nodules: "Good Clinical Practice Recommendations" for Austria: An interdisciplinary statement from the following professional associations: Austrian Thyroid Association (OSDG), Austrian Society for Nuclear Medicine and Molecular Imaging (OGNMB), Austrian Society for Endocrinology and Metabolism (OGES), Surgical Endocrinology Working Group (ACE) of the Austrian Surgical Society (OEGCH). Wien Med Wochenschr 2020;170:6-14. [Crossref] [PubMed]
- National Institute for Health and Care Excellence. Ultrasound- guided percutaneous radiogrequency ablation for benign thyroid nodules. Interventional procedure guidance [IPT562] [Internet]. London: National Institute for Health and Care Excellence, 2016 (cited 2016 Jun 22]. Available online: https://www.nice.org.uk/guidance/ipg562
- Bernardi S, Giudici F, Cesareo R, et al. Five-Year Results of Radiofrequency and Laser Ablation of Benign Thyroid Nodules: A Multicenter Study from the Italian Minimally Invasive Treatments of the Thyroid Group. Thyroid 2020;30:1759-70. [Crossref] [PubMed]
- Gharib H, Hegedus L, Pacella CM, et al. Nonsurgical, image-guided, minimally invasive therapy for thyroid nodules. J Clin Endocrinol Metab 2013;98:3949-57. [Crossref] [PubMed]
- Ha EJ, Baek JH, Kim KW, et al. Comparative efficacy of radiofrequency and laser ablation for the treatment of benign thyroid nodules: systematic review including traditional pooling and bayesian network meta-analysis. The Journal of Clinical Endocrinology & Metabolism 2015;100:1903-11. [Crossref] [PubMed]
- Trimboli P, Castellana M, Sconfienza LM, et al. Efficacy of thermal ablation in benign non-functioning solid thyroid nodule: A systematic review and meta-analysis. Endocrine 2020;67:35-43. [Crossref] [PubMed]
- Sim JS, Baek JH, Lee J, et al. Radiofrequency ablation of benign thyroid nodules: depicting early sign of regrowth by calculating tidal volume. Int J Hyperthermia 2017;33:905-10. [Crossref] [PubMed]
- Deandrea M, Sung JY, Limone P, et al. Efficacy and safety of radiofrequency ablation versus observation for nonfunctioning benign thyroid nodules: a randomized controlled International Collaborative Trial. Thyroid 2015;25:890-6. [Crossref] [PubMed]
- Deandrea M, Trimboli P, Garino F, et al. Long-term Efficacy of a single session of RFA for Benign Thyroid Nodules: A Longitudinal 5-year observational study. J Clin Endocrinol Metab 2019;104:3751-6. [Crossref] [PubMed]
- Cesareo R, Palermo A, Pasqualini V, et al. Radiofrequency ablation for the management of thyroid nodules: A critical appraisal of the literature. Clinical Endocrinology 2017;87:639-48. [Crossref] [PubMed]
- Papini E, Monpeyssen H, Frasoldati A, et al. 2020 European Thyroid Association Clinical Practice Guideline for the Use of Image-Guided Ablation in Benign Thyroid Nodules. Eur Thyroid J 2020;9:172-85. [Crossref] [PubMed]
- Fuller CW, Nguyen SA, Lohia S, et al. Radiofrequency ablation for treatment of benign thyroid nodules: Systematic Review. Laryngoscope 2014;124:346-53. [Crossref] [PubMed]
- Baek JH, Kee JH, Sung JY, et al. Korean Society of Thyroid Radiology. Complications encountered in the treatment of benign thyroid nodules with US-guided radiofrequency ablation: a multicenter study. Radiology 2012;262:335-42. [Crossref] [PubMed]
- Ha EJ, Baek JH, Lee JH. The efficacy and complications of radiofrequency ablation of thyroid nodules. Curr Opin Endocrinol Diabetes Obes 2011;18:310-4. [Crossref] [PubMed]
- Kim C, Lee JH, Choi YJ, et al. Complications encountered in ultrasonography-guided radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers. Eur Radiol 2017;27:3128-37. [Crossref] [PubMed]
- Wang JF, Wu T, Hu KP, et al. Complications following radiofrequency ablation of benign thyroid nodules: a systematic review. Chin Med J (Engl) 2017;130:1361-70. [Crossref] [PubMed]
- Lee M, Baek JH, Suh CH, et al. Clinical practice guidelines for radiofrequency ablation of benign thyroid nodules: a systematic review. Ultrasonography 2020. [Crossref] [PubMed]
- Deandrea M, Limone P, Basso E, et al. US-guided percutaneous radiofrequency thermal ablation for the treatment of solid benign hyperfunctioning or compressive thyroid nodules. Ultrasound Med Biol 2008;34:784-91. [Crossref] [PubMed]
- Hamidi O, Callstrom MR, Lee RA, et al. Outcomes of Radiofrequency Ablation Therapy for Large Benign Thyroid Nodules: A Mayo Clinic Case series. Mayo Clin Proc 2018;93:1018-25. [Crossref] [PubMed]
- Haugen BR, Alexander EK, Bible KC, et al. 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid 2016;26:1-133. [Crossref] [PubMed]
- Ross DS, Burch HB, Cooper DS, et al. 2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis. Thyroid 2016;26:1343-421. [Crossref] [PubMed]
- Vaiman M, Nagibin A, Hagag P, et al. Hypothyroidism following partial thyroidectomy. Otolaryngol Head Neck Surg 2008;138:98-100. [Crossref] [PubMed]
- Ha EJ, Baek JH, Lee JH, et al. Radiofrequency ablation of benign thyroid nodules does not affect thyroid function in patients with previous lobectomy. Thyroid 2013;23:289-93. [Crossref] [PubMed]
- Sung JY, Baek JH, Jung SL, et al. Radiofrequency ablation for autonomously functioning thyroid nodules: a multicenter study. Thyroid 2015;25:112-7. [Crossref] [PubMed]
- Bernardi S, Stacul F, Michelli A, et al. 12-month efficacy of a single radiofrequency ablation on autonomously functioning thyroid nodules. Endocrine 2017;57:402-8. [Crossref] [PubMed]
- Cesareo R, Naciu AM, Iozzino M, et al. Nodule size as predictive factor of efficacy of radiofrequency ablation in treating autonomously functioning thyroid nodules. Int J Hyperthermia 2018;34:617-23. [Crossref] [PubMed]
- Cappelli C, Franco F, Pirola I, et al. Radiofrequency ablation of functioning and non-functioning thyroid nodules: a single institution 12-month survey. J Endocrinol Invest 2020;43:477-82. [Crossref] [PubMed]
- Cervelli R, Mazzeo S, Boni G, et al. Comparison between radioiodine therapy and single-session radiofrequency ablation of autonomously functioning thyroid nodules: a retrospective study. Clin Endocrinol (Oxf) 2019;90:608-16. [Crossref] [PubMed]
- Cesareo R, Palermo A, Benvenuto D, et al. Efficacy of radiofrequency ablation in autonomous functioning thyroid nodules. A systematic review and meta-analysis. Rev Endocr Metab Disord 2019;20:37-44. [Crossref] [PubMed]
- Sung JY, Baek JH, Kim KS, et al. Single-session treatment of benign cystic thyroid nodules with ethanol versus radiofrequency ablation: a prospective randomized study. Radiology 2013;269:293-300. [Crossref] [PubMed]
- Ito Y, Miyauchi A, Kihara M, et al. Patient age is significantly related to the progression of papillary microcarcinoma of the thyroid under observation. Thyroid 2014;24:27-34. [Crossref] [PubMed]
- Sugitani I, Toda K, Yamada K, et al. Three distinctly different kinds of papillary thyroid microcarcinoma should be recognized: our treatment strategies and outcomes. World J Surg 2010;34:1222-31. [Crossref] [PubMed]
- Zhang M, Tufano R, Russell JO, et al. Ultrasound-guided Radiofrequency ablation versus Surgery for Low-Risk Papillary Thyroid Microcarcinoma: Results of over 5 years follow up. Thyroid 2020;30:408-17. [Crossref] [PubMed]
- Kim JH, Baek JH, Sung JY, et al. Radiofrequency ablation of low-risk small papillary thyroidcarcinoma: preliminary results for patient’s ineligible for surgery. Int J Hyperthermia 2017;33:212-9. [Crossref] [PubMed]
- Xiao J, Zhang M, Zhang Y, et al. Efficacy and safety of ultrasonography-guided radiofrequency ablation for the treatment of T1bN0M0 papillary thyroid carcinoma: a retrospective study. Int J Hyperthermia 2020;37:392-8. [Crossref] [PubMed]
- Zhang Y, Zhang MB, Luo YK, et al. Effect of chronic lymphocytic thyroiditis on the efficacy and safety of ultrasound-guided radiofrequency ablation for papillary thyroid microcarcinoma. Cancer Med 2019;8:5450-8. [Crossref] [PubMed]
- Jeong SY, Baek JH, Choi YJ, et al. Radiofrequency ablation of primary thyroid carcinoma: efficacy according to the types of thyroid carcinoma. Int J Hyperthermia 2018;34:611-6. [Crossref] [PubMed]
- Cakir B, Toploglu O, Gul K, et al. Ultrasound-guided percutaneous laser ablation treatment in inoperable aggressive course anaplastic thyroid carcinoma: the introduction of a novel alternative palliative therapy - second experience in the literature. J Endocrinol Invest 2007;30:624-5. [Crossref] [PubMed]
- Shih SR, Shun CT, Su DH, et al. Follicular variant of papillary thyroid carcinoma: Diagnostic limitations of fine needle aspiration cytology. Acta Cytol 2005;49:383-6. [Crossref] [PubMed]
- Gulcelik NE, Gulcelik MA, Kuru B. Risk of malignancy in patients with follicular neoplasm: Predictive value of clinical ultrasonographic features. Arch Otolaryngol Head Neck Surg 2008;134:1312-5. [Crossref] [PubMed]
- Ha SM, Sung JY, Baek JH, et al. Radiofrequency ablation of small follicular neoplasms: initial clinical outcomes. Int J Hyperthermia 2017;33:931-7. [Crossref] [PubMed]
- Dobrinja C, Bernardi S, Fabris B, et al. Surgical and pathological changes after radiofrequency ablation of thyroid nodules. Int J Endocrinol 2015;2015:576576. [Crossref] [PubMed]
- Hay ID, Bergstralh EJ, Goellner JR, et al. Predicting outcome in papillary thyroid carcinoma: development of a reliable prognostic scoring system in a cohort of 1779 patients surgically treated at one institution during 1940 through 1989. Surgery 1993;114:1050-7. [PubMed]
- Samaan NA, Schultz PN, Hickey RC, et al. The results of various modalities of treatment of well differentiated thyroid carcinomas: a retrospective review of 1599 patients. J Clin Endocrinol Metab 1992;75:714-20. [PubMed]
- Baek JH, Kim YS, Sung JY, et al. Locoregional control of metastatic well-differentiated thyroid cancer by ultrasound-guided radiofrequency ablation. AJR Am J Roentgenol 2011;197:W331-6. [Crossref] [PubMed]
- Zhao Q, Tian G, Kong D, et al. Meta-analysis of radiofrequency ablation for treating the local recurrence of thyroid cancers. J Endocrinol Invest 2016;39:909-16. [Crossref] [PubMed]
- Suh CH, Baek JH, Choi YJ, et al. Efficacy and safety of radiofrequency and ethanol ablation for treating locally recurrent thyroid cancer: A systematic review and meta-analysis. Thyroid 2016;26:420-8. [Crossref] [PubMed]
- Chung SR, Baek JH, Choi YJ, et al. Longer-term outcomes of radiofrequency ablation for locally recurrent papillary thyroid cancer. Eur Radiol 2019;29:4897-903. [Crossref] [PubMed]
- Park KW, Shin JH, Han BK, et al. Inoperable symptomatic recurrent thyroid cancers: preliminary results of radiofrequency ablation. Ann Surg Oncol 2011;18:2564-8. [Crossref] [PubMed]
Cite this article as: Pace-Asciak P, Russell JO, Tufano RP. Surgical perspective on radiofrequency ablation of thyroid tumors. Ann Thyroid 2020;5:25.