Clinical practice guidelines for radiofrequency ablation of benign thyroid nodules: a systematic review

Early efficacy of radiofrequency ablation for multifocal T1N0M0 papillary thyroid carcinoma: a multicenter study

OBJECTIVES

This study aimed to assess the efficacy and safety of radiofrequency ablation (RFA) for multifocal papillary thyroid carcinoma (M-PTC) and compare these outcomes with those for unifocal papillary thyroid carcinoma (U-PTC).

METHODS

This retrospective multicenter study included 465 patients (367 women and 98 men) who underwent RFA for either U-PTC (411 patients) or M-PTC (54 patients) between May 2015 and October 2022. Patients were followed up at 1, 3, 6, and 12 months post-RFA, then every 6 months in the second year, and annually thereafter. After 1:1 propensity score matching (PSM), local tumor progression rate (LTP), tumor volume, volume reduction rate (VRR), tumor complete response rate (CDR), and complications were evaluated and compared between the M-PTC and U-PTC groups during the follow-up period.

RESULTS

The median follow-up time was 23 months. The median follow-up time for the U-PTC and M-PTC groups was 23 months and 23.5 months, respectively. The overall local tumor progression rate was 0.9% (4/465), and the overall complication rate was 0.6% (3/465). After PSM, no significant differences were observed between the U-PTC and M-PTC groups regarding tumor volume (p = 0.377), VRR (p = 0.151), CDR (50% vs. 44.2%, p = 0.556), or LTP (1.9% vs. 0%, p = 0.556). Additionally, the complication rates were not significantly different between the groups (1.03% vs. 2.5%, p = 0.343).

CONCLUSION

After adequate preoperative evaluation, RFA is an effective and safe treatment for appropriately selected patients with M-PTC, with a prognosis similar to that of U-PTC.

Comparison of Microwave Ablation and Lobectomy in the Treatment of Benign Thyroid Nodules

PURPOSE

The purpose of this study is to evaluate the efficacy, safety, and advantages of microwave ablation (MWA) compared to lobectomy in the treatment of benign thyroid nodules.

METHODS

A total of 105 patients were included in the study, 49 in the MWA group and 56 in the surgical group. The mean age of the patients in the MWA group was 49.5 (±12.8) and 40.2 (±10.1) in the surgical group (p < 0.001). 81.6% of the patients in the MWA group were female and 18.4% were male. 83.9% of the patients in the surgical group were male and 16.1% were female (p = 0.75). Patients were followed for at least 12 months. The study was completed by comparing the two groups in terms of surgery-procedure times, complications, nodule sizes, thyroid function tests, symptoms, volume reduction rates (VRR), and cosmetic improvement scores.

RESULTS

The mean maximum nodule diameter in the patient group who underwent MWA was 3.5 (±1) cm at the beginning and 2.3 (±0.9) cm at the end of the 12th month (p < 0.001). VRR was 73.4% (±14.8) at the end of the 12th month (p < 0.001). Cosmetic score was 2.5 (±1) at the first month, 1.7 (±1.1) at the third month, 1 (±1) at the sixth month, and 0.6 (±0.7) at the 12th month (p < 0.001). The procedure time was 15.4 (±4.4) minutes in the patients in the MWA group, while it was 70.7 (±17.2) minutes in the surgical group (p < 0.001). No complications developed in 48 patients (98%) in the MWA group and 38 patients (67.9%) in the surgical group (p = 0.005). Voice change occurred in three patients (5.4%) in the surgical group, hematoma in two (3.6%) patients and voice change in one (1.8%) patient in the MWA group. Hypothyroidism developed in eight patients in the surgical group, while hypothyroidism did not develop in the MWA group (p = 0.007).

CONCLUSION

MWA is a safe and effective treatment method for benign thyroid nodules. It has many advantages over thyroidectomy, such as fewer complications, shorter procedure time, no need for hospitalization and general anesthesia, and good cosmetic results.

CLINICAL SIGNIFICANCE

Compared with surgery, MWA is a safe, effective, and cost-effective treatment for benign thyroid nodules.

Resolution of Sleep Apnea After Radiofrequency Ablation of Goiter

Background: Obstructive sleep apnea (OSA) and nontoxic multinodular goiter are conditions that often coexist. Treatments of both conditions have evolved over time, but continuous positive airway pressure (CPAP), oral appliances, or surgical therapy are often needed. Radiofrequency ablation (RFA) of the soft palate and base of tongue has been applied as a newer alternative therapy for OSA. RFA is also an increasingly used approach for thyroid nodules and goiter, but previously had no known connection to OSA. Case Presentation: A 59-year-old female with a known history of multinodular goiter and moderate OSA was referred to our endocrine surgery clinic. The goiter was found to have mediastinal extension, documented longitudinal growth of the dominant nodule, cosmetic deformity of the neck, and tracheal deviation. The patient underwent thyroid RFA as nonoperative treatment for her goiter. Within a month of her procedure, she also self-reported a subjective reduction in apneic events and later underwent a formal home sleep study demonstrating an apnea-hypopnea index (AHI) change from 15.8/h at diagnosis to 2.9/h currently, signifying resolution of her OSA. Her treated nodule had 92% volume reduction on 18-month follow-up visit. Conclusion: To our knowledge, this is the first reported case of OSA cured in a patient undergoing RFA for goiter. Goiter-associated sleep apnea remains inadequately described in the literature and warrants further investigations on prevalence and management. Thyroidectomy continues to be the definitive treatment for goiter, with some studies suggesting secondary efficacy for OSA. RFA is now established as a first-line option for symptomatic thyroid nodules, but previously had no described benefit to OSA symptoms. This report illustrates that RFA of thyroid nodules could be offered to patients as both an effective nonsurgical option for goiter as well as a potential cure for their OSA to free them from nightly CPAP usage.

Configuring thermal ablation volumes for treatment of distinct tumor shapes: a repeatability study using a robotic approach

Objectives

In the current clinical practice of thermal ablation treatment for liver tumors, achieving consistent and effective clinical outcomes across tumors of varying shapes, sizes and locations remains challenging. The aim of this study was to evaluate the repeatability of a novel robotic approach for configurable ablation of distinct tumor shapes and compare it to the standard ablation technique for creating ellipsoidal ablation volumes.

Materials and methods

The repeatability was evaluated in terms of width variability in created ablation volumes. Using a robotic navigation platform, custom ablation profiles configured with power, time, and distance parameters were designed to create four distinct ablation shapes. The profiles were applied for microwave ablation in a tissue-mimicking liver model. For comparison of ablation shape variability, six standard ellipsoidal shapes were created using the standard ablation technique by configuring power and time parameters. For each sample, the resulting ablation area was segmented, and the resulting shape width and length were calculated at the measurement points. Width variability was calculated as the median of the absolute pairwise differences in width at each measurement point, and configurable versus standard ablation shapes were compared using the Mann-Whitney U test.

Results

All tissue-mimicking samples were successfully ablated using both configurable (n = 48) and standard ablation technique (n = 35). Study findings revealed noninferiority regarding repeatability of created ablation shapes using the robotic platform for configurable ablation, compared to created standard ellipsoidal ablation shapes (p < 0.001, 95% CI ≤ -0.05 mm, Δ = -0.22 mm). Median repeatability of created configurable shapes was 1.00 mm, and for standard shapes 1.22 mm. Maximal repeatability for both groups was below 3 mm.

Conclusion

The repeatability of configurable ablation shapes was observed to be noninferior to the standard ablation shapes. Achieving configurable ablation volumes underscores the potential to advance personalization of thermal ablation treatment and broaden its applicability to distinct tumor cases. In-vivo validation is needed for evaluation of the clinical implications of this novel treatment technique.

Trends in thyroid function following radiofrequency ablation of benign, nonfunctioning thyroid nodules: A single institution review

BACKGROUND

Radiofrequency ablation (RFA) effectively reduces volume and improves symptoms of benign, non-functioning thyroid nodules (NFTNs). Given RFA's unclear impact on thyroid function, we examined post-RFA trends in thyroid hormones and antibodies.

METHODS

A retrospective cross-sectional analysis was conducted of patients treated at Columbia University with RFA for benign NFTNs between August 2019 and July 2023. Thyroid function tests were recorded pre-RFA and repeated 3, 6, and 12 months post-RFA.

RESULTS

We analyzed 185 patients with 243 benign NFTNs who underwent RFA. Volume reduction ratio increased post-RFA. Mean TSH increased to 2.4 mlU/L (p ​= ​0.005) at 3 months post-RFA and decreased to 1.8 mlU/L (p ​= ​0.551) by 12 months post-RFA. Tg and TPO antibody levels peaked at 6 months post-RFA (103.1 IU/mL, p ​= ​0.868 and 66.6 IU/mL, p ​= ​0.523, respectively).

CONCLUSIONS

With expected volume reduction post-RFA, we observed transient relative hypothyroidism as well as transient increases in thyroid antibodies, with normalization of these changes within 12 months.

Efficacy of microwave ablation in the treatment of large benign thyroid nodules: a multi-center study

OBJECTIVE

To evaluate the efficacy, safety, and improvement of symptoms by ultrasound-guided microwave ablation (MWA) for patients with large benign thyroid nodules (BTNs).

METHODS

Eighty-seven patients with 87 BTNs (≥ 4 cm) treated with MWA between April 2015 and March 2021 were enrolled in this retrospective multicenter study, with clinical and ultrasound examinations performed at the 1st, 3rd, 6th, and 12th months. A multivariable linear mixed effects model was employed to explore the alterations in volume and volume reduction ratio (VRR), as well as the potential factors associated with VRR.

RESULTS

The mean age of the 87 patients was 45.69 ± 14.21 years (range 18-76 years), and the ratio of men to women was 1:4.8. The mean volumes were much decreased at the 12th month after ablation compared to the initial volumes (p < .001). The mean VRR was 76.09% at the 12th month. The technique efficacy (VRR > 50%) was 90.80% at the 12th month. A multivariate analysis revealed that VRR was related to the initial volume (p = .015), annular flow (p = .010), and nodule composition (p = .024). The mean symptomatic score decreased from 4.40 ± 0.28 to 0.26 ± 0.06 at the 12th month (p < .001). At the same time, the mean cosmetic score decreased from 3.22 ± 0.10 to 1.31 ± 0.08 (p < .001).

CONCLUSION

MWA could serve as a safe and effective therapy for large BTNs, significantly reducing the volume of BTNs and significantly improving compressive symptoms and appearance problems.

CLINICAL RELEVANCE STATEMENT

Microwave ablation could serve as a safe and effective therapy for large benign thyroid nodules, leading to significant volume reduction and satisfied symptom and cosmetic alleviation period.

KEY POINTS

• This multicenter study investigated the feasibility and safety of microwave ablation for large benign thyroid nodules. • After ablation, the nodule volume was significantly reduced, and patients' symptoms and appearance problems were significantly improved. • Microwave ablation is feasible for large benign thyroid nodules and has been a supplement treatment.

Cervical plexus block enhanced pain control for unilateral thermal ablation of thyroid nodules

Background

Despite being minimally invasive, thermal ablation (TA) of thyroid nodules may still cause significant pain during and shortly afterwards. Conventional analgesia relies on perithyroidal local anesthesia (PLA) with or without sedation. The use of cervical plexus block (CPB) has been extensively studied in thyroidectomy, but never studied in TA of the thyroid gland. This study examined whether adding ultrasound-guided CPB to PLA and sedation could further reduce post-operative pain in unilateral TA of thyroid nodules.

Methods

Consecutive patients aged ≥18 years undergoing unilateral radiofrequency ablation (RFA) or microwave ablation (MWA) of thyroid nodules were reviewed. Group I patients did not receive CPB, and Group II patients received CPB by bupivacaine injection between the sternocleidomastoid muscle (SCM) and prevertebral fascia on the treatment side. Pain was charted immediately and 4 hours after ablation using a numeric rating scale (NRS) of 0-10. The Quality-of-Recovery-9 (QoR9) questionnaire was completed.

Results

Over an 18-month period, 100 patients underwent unilateral thyroid ablation (Group I, n=50; Group II, n=50). Comparable baseline patient demographics, nodule characteristics, ablation parameters were noted (P>0.05). Significantly lower immediate NRS {1 [0-3] vs. 4 [1.3-6], P<0.001}, 4-hour NRS {1 [0-3] vs. 2 [0-4], P=0.04}, and more zero immediate NRS (44% vs. 14%, P=0.001) was observed in Group II. Total QoR9 scores were comparable {16 [12-17] vs. 15 [12-17], P=0.72}. No adverse events occurred. All patients were discharged within the same day.

Conclusions

Adding ultrasound-guided CPB further enhanced pain control following unilateral TA of thyroid nodules, without compromising quality of recovery or same-day discharge.

Advances in influence factors of ultrasound-guided percutaneous thermal ablations for benign thyroid nodules: A review

Ultrasound-guided percutaneous thermal ablation is a safe and effective minimally invasive treatment for benign thyroid nodules, which is now widely used in the world. Studies have found that some preoperative factors played an important role in the outcome of thermal ablation. This paper mainly reviews the various factors affecting the efficacy of ultrasound-guided percutaneous thermal ablation in the treatment of benign thyroid nodules to provide a variety of perspectives for the clinical and to promote the postoperative outcome of patients.

Comparison of the effectiveness of ultrasound-guided radiofrequency ablation and conventional open thyroidectomy in the treatment of benign thyroid nodules

Objective

To compare the effectiveness of ultrasound (US)-guided radiofrequency ablation (RFA) and conventional open thyroidectomy (OT) in the treatment of benign thyroid nodules (BTN).

Methods

Medical records of 103 patients with BTN undergoing surgical treatment at The Affiliated Jiangning Hospital of Nanjing Medical University from March 2019 to March 2022 were retrospectively analyzed. Records show that 53 patients underwent US-guided RFA (observation group) and 50 patients underwent conventional OT (control group). Perioperative indicators (operation duration, intraoperative blood loss, postoperative hospital stay, incision length, and VAS score 12h and 24h after surgery), complications, thyroid function, and nodule recurrence in both groups were compared and analyzed.

Results

Perioperative indicators of patients in the observation group were better, and the visual analogue scale (VAS) scores at 12 and 24 hours after the surgery were lower than those of the control group (p<0.05). The incidence of complications in the observation group was significantly lower than that in the control group (p<0.05). There was no statistically significant difference in the preoperative levels of thyroid-stimulating hormone (TSH), serum free thyroxine (FT4) and serum free triiodothyronine (FT3) between the two groups (p>0.05). The postoperative TSH levels in the observation group increased compared to the preoperative levels and were higher than those in the control group, while FT4 and FT3 levels decreased after surgery and were lower than those in the control group (p<0.05).

Conclusions

Compared to conventional open thyroidectomy, US-guided RFA is associated with less trauma, faster recovery, fewer complications, and less impact on thyroid function in the treatment of patients with BTN.

Salvage radiofrequency ablation followed by external beam radiotherapy for inoperable recurrent differentiated thyroid cancer

PURPOSE

The treatment of recurrent thyroid cancer with critical organ invasion is challenging. The combination of radiofrequency ablation (RFA) and external beam radiation therapy (EBRT) has been proposed as an effective option. This study evaluates outcomes for inoperable residual/recurrent differentiated thyroid cancer (rDTC) patients treated with RFA followed by EBRT.

MATERIALS AND METHODS

Patients with rDTC treated with RFA followed by EBRT were retrospectively studied. RFA was performed using a free-hand, 'moving-shot' technique under US or CT guidance. For lesions invading critical structures intolerant to 'en bloc' high-temperature RFA, limited-field EBRT using 6- or 10-MV photons was used for adjuvant treatment at a dose of 66 Gy in 33 daily fractions. Toxicities and outcomes were reviewed.

RESULTS

Between April 2020 and January 2022, 11 patients with 14 rDTC lesions underwent RFA followed by EBRT. Five patients had metastatic lesions at rDTC diagnosis. With a median follow-up period of 33.7 months, all patients maintained locoregional control, while achieving a 2-year survival rate of 90.9%. This combined treatment achieved a volume reduction ratio of 92.1% ± 5.1%. The mean nadir thyroglobulin level in patients without initial distant metastases after treatment was 1.40 ± 0.81 ng/ml. Regarding treatment-related complications, one patient (9%) experienced temporary hoarseness after RFA, grade 2 radiation dermatitis occurred in 3 patients (27.2%), and grade 2 dysphagia was noted in 4 patients (36.4%). No grade 3 or greater toxicities occurred.

CONCLUSIONS

Salvage RFA followed by EBRT is feasible, effective and safe for patients with rDTC.

Radiofrequency ablation as a novel modality in Ecuador for treating toxic thyroid nodules: a case series

Background

Treating hyperthyroidism induced by autonomously functioning thyroid nodules (AFTNs) through radioactive iodine and surgery often results in undesirable hypothyroidism. Radiofrequency ablation (RFA) has arisen as a favorable option. European guidelines recommend RFA for small AFTN in young patients, aiming to restore normal thyroid function and avoid irradiation. The procedure, costing between 500 and 1,000 euros, is conducted in outpatient clinics and takes 15 to 40 minutes. We aimed to describe the clinical outcomes of AFTN patients treated with RFA in Ecuador.

Case Description

We included eight patients with toxic thyroid nodules suppressed thyroid-stimulating hormone (TSH), with symptomatic hyperthyroidism. The mean age was 41.63 years [standard deviation (SD): 14.97 years]. The median follow-up time was 8 months. Nodules were solid (37.5%) or predominantly solid (62.5%). The mean volume pre-RFA was 5.27 mL [interquartile range (IQR), 0.70-9.66 mL]. After ablation, the median volumes at 1, 3, and 6 months were [2.25 (SD: 1.67; P<0.12), 1.28 (SD: 1.1; P=0.013), and 1.37 (SD: 1; P=0.23) mL], respectively. The volume reduction (VR) was 45.8%, 75.1%, and 69.7% at 1-, 3-, and 6-month follow-up, respectively.

Conclusions

RFA holds promise as a potential therapeutic approach for managing AFTNs. The success and the feasibility of RFA in this series are consistent with other studies as a treatment option in young patients with small AFTN. However, more research is needed to establish comprehensive guidelines and protocols to maximize the benefits of RFA in AFTNs.

Thyroid Ethanol and Radiofrequency Ablation: A Call for Patient-Friendly Online Resources

INTRODUCTION

The multiple treatment options available to patients with thyroid nodules can generate uncertainty and confusion. Radiofrequency ablation (RFA) and ethanol ablation (EA) are two alternative modalities to manage thyroid nodules. As patients more frequently utilize online resources to guide their decision-making, the quality of such resources must be evaluated. The goal of this study was to assess the quality of online patient materials relating to RFA and EA compared to standard thyroidectomy.

METHODS

The terms "thyroidectomy," "thyroid radiofrequency ablation," and "thyroid ethanol ablation" were searched on Google. Flesch Reading Ease (FRE), Flesch-Kincaid Grade Level (FKGL), Simple Measure of Gobbledygook (SMOG), and Patient Education Materials Assessment Tool (PEMAT) understandability and actionability were calculated for each website. Statistical analysis was conducted on SPSS Statistics. Google trends were used to determine search interest for each term (May 2016 - May 2021).

RESULTS

Of the 77 websites that met our inclusion criteria (30 thyroidectomy sites, 30 RFA sites, and 17 EA sites), the average FRE, FKGL, and SMOG scores of the RFA websites were significantly worse than those of the thyroidectomy websites (p < 0.05). The FKGL and SMOG scores of the EA websites were significantly worse than those of the thyroidectomy websites (p < 0.05). The average understandability and actionability scores for thyroidectomy websites were significantly higher than those of RFA and EA websites (p < 0.05).

CONCLUSION

Ablation websites have lower search interest, readability, validity, understandability, and actionability scores in comparison to traditional thyroidectomy websites. Our findings emphasize the need to consider readability and PEMAT scores when developing online educational resources for ablative alternatives to thyroidectomy to allow for greater patient accessibility.

Novel and Advanced Ultrasound Techniques for Thyroid Thermal Ablation

Thyroid radiofrequency ablation and microwave ablation are widely adopted minimally invasive treatments for diverse thyroid conditions worldwide. Fundamental skills such as the trans-isthmic approach and the moving shot technique are crucial for performing thyroid ablation, and advanced techniques, including hydrodissection and vascular ablation, improve safety and efficacy and reduce complications. Given the learning curve associated with ultrasound-guided therapeutic procedures, operators need training and experience. While training models exist, limited attention has been given to ultrasound maneuvers in ablation needle manipulation. This article introduces two essential maneuvers, the zigzag moving technique and the alienate maneuver, while also reviewing the latest ultrasound techniques in thyroid ablation, contributing valuable insights into this evolving field.

Radiofrequency Ablation for Benign Nodules and for Cancer, Too?

Radiofrequency ablation (RFA) is a minimally invasive procedure performed under ultrasound guidance that offers the ability to significantly reduce the size of benign thyroid nodules. Although application for benign nodules has only emerged during the past 5 to 10 years in North America, RFA has an impressive track record of nodule reduction, compressive and cosmetic symptom improvement, and excellent safety profile without the morbidity of open surgery. The role of RFA in autonomous functioning nodules, thyroid cancer, and indeterminate nodules is controversial and remains an area of investigation.

From ablation to operation: Unraveling the surgical outcomes and complications of thyroidectomy after radiofrequency ablation

BACKGROUND

Radiofrequency ablation is a minimally invasive treatment for thyroid nodules; however, concerns exist regarding its impact on subsequent thyroid surgery. We compared surgical outcomes and complications between patients undergoing thyroidectomy after radiofrequency ablation (post-radiofrequency ablation thyroidectomy group) and those without prior radiofrequency ablation (non-radiofrequency ablation thyroidectomy group).

METHODS

We retrospectively analyzed thyroidectomy patients, comparing post-radiofrequency ablation thyroidectomy and non-radiofrequency ablation thyroidectomy groups, examining demographics, nodule characteristics, surgical techniques, and complications.

RESULTS

The study included 96 patients (73 in the non-radiofrequency ablation thyroidectomy group and 23 in the post-radiofrequency ablation thyroidectomy group). The mean age was 53.3 ± 14.4 years, with 78.1% female patients and 36.5% African American patients. Median operative time was similar between the post-radiofrequency ablation thyroidectomy (110 minutes) and the non-radiofrequency ablation thyroidectomy (92 minutes) cohorts (P = .40). Complications were reported in 13 patients, without significant differences between groups (P = .54). No permanent complications, including nerve injury or hypoparathyroidism, were reported in either cohort. Prior radiofrequency ablation treatment did not increase the risk of complications (odds ratio = 3.48, 95% confidence interval = 0.70-17.43, P = .16).

CONCLUSION

Our work found no differences in outcomes or safety in patients undergoing thyroidectomy with or without previous radiofrequency ablation treatment, potentiating the post-radiofrequency ablation thyroidectomy group as a safe management option. Accordingly, this may reassure both clinicians and patients of the safety of radiofrequency ablation in treating patients with thyroid nodules.

Radiofrequency Ablation for Benign Thyroid Nodules

CONTEXT

Thermal ablative techniques of the thyroid have recently gained clinical traction as a therapeutic alternative that provides symptomatic relief and confers potential advantages over surgery. A truly multidisciplinary technique, thyroid ablation is currently performed by endocrinologists, interventional radiologists, otolaryngologists, and endocrine surgeons. Radiofrequency ablation (RFA), specifically, has seen widespread adoption, particularly in the treatment of benign thyroid nodules. This review summarizes current evidence on the application of RFA in benign thyroid nodules, and provides a start to finish overview of procedural preparation, performance, and outcomes.

EVIDENCE ACQUISITION

A narrative review of literature focusing on RFA in the treatment of benign nodular disease was performed. Emphasis was placed on consensus statements, best practice guidelines, multi-institutional studies, and systematic reviews to summarize key concepts in candidacy, techniques, expectations, and outcomes.

FINDINGS

RFA is increasingly recognized as a first-line treatment strategy in the management of symptomatic nonfunctional benign thyroid nodules. It can also be considered in functional thyroid nodules with small volumes or in patients ineligible for surgery. A targeted and efficacious technique, RFA results in gradual volume reduction that preserves the function of the surrounding thyroid parenchyma. Proper procedural technique, proficiency in ultrasound, and experience in ultrasound-guided procedures are instrumental to maintaining low complication rates and achieving successful ablation outcomes.

CONCLUSIONS

In pursuit of a personalized approach, physicians across disciplines are increasingly incorporating RFA into their treatment algorithms, most commonly for benign nodules. As with any intervention, thoughtful selection and implementation ensure a safe procedure with optimal patient benefit.

Comparison of the effects of contrast-enhanced ultrasound and conventional ultrasound-guided radiofrequency ablation on benign thyroid nodules

Objective

To compare the effect of contrast-enhanced ultrasound (CEUS) and conventional ultrasound-guided radiofrequency ablation (RFA) on benign thyroid nodules (BTNs).

Methods

In this retrospective observational study, the data of 72 patients with BTNs who received RFA treatment in The Fourth Affiliated Hospital of Zhejiang University School of Medicine from January 2020 to December 2021 were retrospectively reviewed and selected. The records showed that 34 patients received RFA under the guidance of conventional ultrasound (conventional ultrasound group) and 38 patients received RFA under the guidance of CEUS (CEUS group). The effect of treatment, complications and recurrence of the two groups were compared and analyzed.

Results

There was a smaller volume of thyroid nodules in the two groups immediately post-operation. The incidence of complications was lower in the CEUS group (5.26%) compared to the conventional ultrasound group (23.53%) (P<0.05). The recurrence rate at 6-months (0.00% vs 11.76%) and 12- months (2.63% vs 20.59%) post-operation was lower in the CEUS group compared to the conventional ultrasound group (P<0.05).

Conclusions

Compared with conventional ultrasound, CEUS-guided RFA is effective in treating BTNs, with smaller postoperative nodule volume, reduced occurrence of surgical complications, and reduced recurrence rate of thyroid nodules.

Comparison of the Efficiency of Radiofrequency and Microwave Ablation Methods in the Treatment of Benign Thyroid Nodules

RATIONALE AND OBJECTIVES

To compare the efficacy of two thermal ablation techniques (radiofrequency vs microwave ablation) in the treatment of benign thyroid nodules.

MATERIALS AND METHODS

A total of 80 patients with 80 nodules underwent thermal ablation of thyroid nodules with either radiofrequency ablation (RFA) (23 females and 14 males; mean age 41 ± 9years) or microwave ablation (MWA) (28 females and 15 males; mean age 45 ± 11years). Ultrasound assessments were made at the 1st, 3rd, 6th, and 12th months after the ablation procedure.

RESULTS

The mean initial volume of the nodules (RFA: 15.6 mL [min 2.5-max 74]; MWA: 40 mL [min 2-max 205]) was statistically significantly different (P < .001). The following were the volume reduction rates of nodules at 1, 3, 6, and 12months, respectively: after RFA: 46.8 ± 13.5%, 62.9 ± 13.6%, 71.6 ± 11.9%, and 77.9 ± 10.3%. After MWA: 38.7 ± 12.5%, 54 ± 15.3%, 59.6 ± 12.5%, and 65 ± 11.3%. For all months, volume reduction rates in the RFA group were significantly higher than those in the MWA group (P < .05). One patient treated by RFA reported an abscess formation and another patient treated by RFA had a self-limiting hematoma, who recovered without any further treatment. Also, in the MWA group, one patient had abscess formation and another patient had transient recurrent nerve paralysis, who recovered with appropriate treatment.

CONCLUSION

Both methods are effective in treating benign thyroid nodules; however, RFA provides a better volume reduction.

Short-term outcome of adrenal radiofrequency ablation of adrenal cysts: a single-center experience

Percutaneous thermal ablation is a minimally invasive treatment for liver, kidney, lung, bone, and thyroid tumors. This treatment also has been used to treat adrenal tumors in patients, but there is no evidence for the efficacy of thermal ablation of adrenal cysts. The present study was performed to analyze the experience of a single center with percutaneous radiofrequency ablation (RFA) of adrenal cysts and to evaluate its efficacy. The present study enrolled all patients who underwent percutaneous RFA for unilateral adrenal cysts from 2019 to 2021. All patients underwent USG-guided percutaneous aspiration of cystic fluid, followed by RFA. A total nine patients with adrenal cysts were included in this study. All of them underwent technically successful percutaneous RFA, with no immediate complication. Follow-up CT 3 months after RFA showed that six of the nine adrenal cysts showed good responses, with reductions in cyst volume ranging from 86.4 to 97.9%. One patient had poor response in the cyst size (volume reduction rate 11.2%). She underwent secondary RFA with resulting that the cyst volume reduced by 91.1%. After a median follow-up period of 17.2 months, eight patients showed no evidence of regrowth. The patient, who showed evidence of regrowth, declined any other treatment and has been under regular surveillance. None of the nine patients developed adrenal insufficiency during the follow-up period. In conclusion, percutaneous RFA is a safe and effective minimally invasive treatment for adrenal cysts, suggesting that percutaneous RFA may be a good alternative option in selected patients.

American Association of Clinical Endocrinology Disease State Clinical Review: The Clinical Utility of Minimally Invasive Interventional Procedures in the Management of Benign and Malignant Thyroid Lesions

OBJECTIVE

The objective of this disease state clinical review is to provide clinicians with a summary of the nonsurgical, minimally invasive approaches to managing thyroid nodules/malignancy, including their indications, efficacy, side effects, and outcomes.

METHODS

A literature search was conducted using PubMed and appropriate key words. Relevant publications on minimally invasive thyroid techniques were used to create this clinical review.

RESULTS

Minimally invasive thyroid techniques are effective and safe when performed by experienced centers. To date, percutaneous ethanol injection therapy is recommended for recurrent benign thyroid cysts. Both ultrasound-guided laser and radiofrequency ablation can be safely used for symptomatic solid nodules, both toxic and nontoxic. Microwave ablation and high-intensity focused ultrasound are newer approaches that need further clinical evaluation. Despite limited data, encouraging results suggest that minimally invasive techniques can also be used in small-size primary and locally recurrent thyroid cancer.

CONCLUSION

Surgery and radioiodine treatment remain the conventional and established treatments for nodular goiters. However, the new image-guided minimally invasive approaches appear safe and effective alternatives when used appropriately and by trained professionals to treat symptomatic or enlarging thyroid masses.

Thyroid-dedicated internally-cooled wet electrode for benign thyroid nodules: experimental and clinical study

BACKGROUND

To assess the effects of radiofrequency ablation (RFA) using an internally-cooled wet (ICW) electrode in ex vivo bovine liver and evaluate the feasibility of the ICW electrode for benign thyroid nodules.

METHODS

We developed an 18-gauge ICW electrode with a microhole at the distal tip for tissue infusion of chilled (0 - 4 °C) isotonic saline (rate = 1.5 ml/min). RFA using ICW and IC electrodes were performed in bovine livers (40 pairs, 1-cm active tip, 50 W, 1-min). We compared the morphological characteristics of ablation zones and presence of carbonization. Twenty patients with benign thyroid nodules larger than 5 ml were prospectively enrolled in a clinical study and underwent ultrasound-guided RFA with ICW electrodes. Ultrasound examinations, laboratory data, and symptom and cosmetic scores were evaluated preprocedure and 1 and 6 months after the procedure.

RESULTS

In the ex vivo study, the ICW achieved significantly larger ablation zones than the IC (p<.001). In the clinical study, ICW electrodes were tolerable in all patients. At last follow-up, nodule volume had decreased from 15.6 ± 12.1 ml to 4.1 ± 4.3 ml (p<.001), and the mean volume reduction ratio (VRR) was 73.3 ± 13.7% at 6.0 months follow-up. Cosmetic and symptom scores were reduced from 3.52 ± 1.03 to 2.65 ± 0.88 and 3.10 ± 2.17 to 0.85 ± 0.99 (both p<.001), respectively. After RFA, thyroid function was well preserved in all patients, and mean thyroglobulin level decreased from 36.6 ± 52.1 ng/ml to 26.9 ± 62.2 ng/ml. One patient experienced a temporary voice change that recovered within a week.

CONCLUSIONS

We developed a thyroid-dedicated ICW electrode that we showed to be feasible and effective in patients with benign thyroid nodules.

Efficacy of radiofrequency ablation for metastatic papillary thyroid cancer with and without initial biochemical complete status

OBJECTIVE

The application of radiofrequency ablation (RFA) for recurrent thyroid cancer has been demonstrated to effectively manage lesions at critical locations, such as abutting the trachea, with limited complications. Comprehensive investigation of both biochemical (B) and structural (S) change after RFA remains limited. We herein present the first single-center experience of RFA for the treatment of locoregional recurrent thyroid cancer in Taiwan.

DESIGN

23 patients were enrolled, and the treatment responses after RFA were divided into four groups (E, S(+), B(+), and SB(+)), and then compared. The RFA technique, follow-up strategy, changes in pre-and post-operative status, and complications are presented. The volume reduction rate at 1, 3, and 6 months, and the differing responses between lesions abutting/not abutting the trachea are also discussed.

RESULTS

In patients with pre-RFA structural and biochemical incomplete (SB(+)) status, presenting with lesion with an initial maximum diameter of >3.2cm, a higher rate of structural incomplete status at the 6-month follow-up was noted in ROC analysis, with a sensitivity of 57% and specificity of 91%. Favorable structural remission after RFA was noted, and 60.9% of patients achieved biochemical complete status. No significant correlation was noted between the trachea-abutted lesion number and complete remission (p= 0.474). No significant difference in RFA efficacy was noted between the lesions abutting/not abutting the trachea.

CONCLUSIONS

This retrospective study reveals that RFA can achieve both structural and biochemical improvements for locoregionally recurrent thyroid cancer, with a low complication rate. Nearly half of the patients achieved an excellent response after RFA, while a favorable treatment response can be achieved despite the lesion abutting the trachea, with a mean VRR of 84.74%.

Efficacy and Safety of Radio Frequency Ablation for Benign Thyroid Nodules: Initial Clinical Experience in United Arab Emirates

Objectives Radio frequency ablation (RFA) to treat thyroid nodules is well known as one of alternative therapeutic modalities. This study aimed to investigate the efficacy and complications of RFA to treat symptomatic benign thyroid nodules in United Arab Emirates.

Materials and Methods Eight-nine benign thyroid nodules of 63 patients were enrolled, who were treated by percutaneous ultrasound (US)-guided RFA from 2017 to 2020, and had following US examinations during 12 months after RFA procedure. Symptomatic score with 10-cm visual scale, cosmetic score with four-point scale, and US findings (nodule diameter, volume, composition and vascularity) were compared before and after RFA procedures. RFA-related complications (hematoma, voice change, hypothyroidism, and hyperthyroidism) were assessed.

Statistical Analysis Paired t test was applied to compare laboratory findings before and after RFA procedure. Multiple linear regression analysis was applied to determine significant factors to predict the efficacy of RFA. One-way analysis of variance was applied to compare volume reduction rate (VRR) at 3, 6, and 12 months.

Results Symptomatic and cosmetic scores were significantly improved (pre-RFA vs. post-RFA; 6.07 ± 1.89 vs. 2.06 ± 1.09, 2.94 ± 0.84 vs. 1.27 ± 0.51, p< 0.001). Nodule diameter (cm), volume (mL) at pre-RFA, post-RFA 3 months, 6 months, and 12 months were 3.86 ± 1.26, 2.64 ± 1.14, 2.06 ± 1.09, 1.82 ± 1.14, and 18.8 ± 18.79, 8.82 ± 12.42, 4.47 ± 5.59, 4.11 ± 9.17 (p< 0.001). VRR (%) was 52.81 ± 23.48 at post-RFA 3 months, 79.77 ± 16.91 at 6 months, and 82.08 ± 19.54 at 12 months. Composition of solidity was a significant predictive factor, related to VRR at post-RFA 12 months (p = 0.003). Complication rate was 12.7% (8 of 63 patients). Major complications did not occur.

Conclusion RFA can be an effective and safe alternative modality to treat benign thyroid nodules, and be preferable to treat symptomatic cystic thyroid nodules in Middle East population.

Radiofrequency ablation of recurrent thyroid cancers: anatomy-based management

Although differentiated thyroid cancer has an excellent prognosis and low mortality, its recurrence rate has been reported to be very high. While surgery is recommended as the standard treatment for recurrent thyroid cancer, reoperation may increase the incidence of complications due to fibrosis and anatomical distortion. In patients with high surgical risk or those who refuse repeated surgery, ultrasonography-guided ablation techniques including radiofrequency ablation, ethanol ablation, and laser ablation are suggested as alternative treatments. In this manuscript, we introduce an anatomy-based management concept for radiofrequency ablation for recurrent thyroid cancer, and present a review of the relevant literature, including indications, basic techniques, clinical outcomes, and complications.

Thermoablation of thyroid nodules reveals excellent results with low morbidity

BACKGROUND

Thermoablation is an attractive treatment of thyroid nodules for its minimal-invasiveness. It remains unclear whether results and morbidity meet the patients' expectations.

OBJECTIVE

The aim of the presented study is to show data obtained after microwave thyroid ablation from a patients' perspective.

METHODS

Indications and preoperative diagnosis were chosen according to international guidelines. Thermoablation was achieved using a CE certified microwave system. The procedures heeded the published recommendations of the European Federation of Societies for Ultrasound in Medicine and Biology. Follow-up included ultrasound, laboratory parameters and a standardized questionnaire.

RESULTS

Thirty patients were enrolled into the study. All patients reported an improvement of complaints following the procedure. Scar formation occurred in 3 cases (10%) with 0.5 ± 1.3 mm length and 0.4 ± 1.0 mm width. No cosmetic, neurological, vocal or pharyngeal complication occurred. Energy required for non-functioning nodules (n= 15, 50%) was 2.56 ± 3.41 kJ/mL, for autonomous adenoma (n= 8, 27%) 0.96 kJ/mL (p< 0.05, t-test).

CONCLUSION

The presented data summarize an initial experience in selected patients and resemble excellent patient reported outcome with minimal morbidity. These preliminary data indicate the majority of patients satisfied with the procedure. Further trials will be required to endorse these findings.

Analyzing the adoption of radiofrequency ablation of thyroid nodules using the diffusion of innovations theory: understanding where we are in the United States?

Thyroid nodules are very common and found in up to 68% of the general U.S. population on ultrasound. Although thyroidectomy has long been the mainstay of treatment for malignant and symptomatic benign thyroid nodules, various interventional ablative techniques have emerged in the last couple of decades as alternative non-surgical treatment options. Globally, the most widely adopted technique has been ultrasound-guided radiofrequency ablation (RFA). RFA of thyroid nodules was first performed in 2002, and there has been an expanding body of evidence since 2006 showing that RFA and other interventional ablative techniques are effective treatments for benign solid thyroid nodules, toxic adenomas, and thyroid cysts. More recently, evidence has emerged that these techniques may be effective treatment for low-risk thyroid cancer and recurrent disease. Despite these findings, the United States has been slow to adopt these techniques, with only a single publication on RFA more than a decade after the first series was published. EM Rogers’ Diffusion of Innovation Theory provides us the appropriate lens to carefully analyze the process of adoption of RFA for thyroid nodules-to understand where we are currently, as well as, the important next steps that must be accomplished in order for RFA and other ablative techniques to be successfully adopted into the management algorithm of thyroid nodules in the United States.

Assessment of thyroid-specific quality of life in patients with benign symptomatic thyroid nodules treated with radiofrequency or ethanol ablation: a prospective multicenter study

Purpose

Radiofrequency ablation (RFA) and ethanol ablation (EA) are effective and safe for benign symptomatic thyroid nodules (BSTNs). However, relatively little is known about the effects of these procedures on patients’ quality of life (QoL). This prospective, multicenter study evaluated the effects of RFA and EA on changes in thyroid-specific QoL in patients with BSTNs and assessed the volume reduction and safety of these procedures.

Methods

Eighty-six consecutive patients with 86 BSTNs were prospectively included from two medical centers. RFA was performed for 55 BSTNs with solidity ≥50% and EA was performed for 31 BSTNs with solidity <50%. QoL was evaluated using an 11-scale, multiple-choice thyroid-specific QoL questionnaire. Nodule characteristics and QoL were evaluated at diagnosis and 1, 6, and 12 months after treatment. Overall QoL was rated from 0 (good) to 4 (poor).

Results

The mean longest size and volume of the index nodule were 4.2±1.5 cm and 21.6±22.1 mL, respectively. Patients received 1.1 treatments on average (range, 1 to 2). Significant post-treatment volume reductions were noted; however, the EA group showed a higher volume reduction than the RFA group at 1 (78.7%-16.1% vs. 49.1%-15.8%), 6 (86.3%-21.7% vs. 73.0%-14.5%), and 12 (90.9%-14.9% vs. 80.3%-12.4%) months. The score for each scale of the QoL questionnaire improved significantly during follow-up (all P<0.001). Overall QoL improved significantly, from 1.7±0.9 at diagnosis to 0.6±0.7 at the 12-month follow-up (P<0.001). There were no major complications.

Conclusion

Both RFA and EA are safe and effective in reducing nodule volume and improving thyroid-specific QoL in patients with BSTNs.

Radiofrequency Ablation of Benign Thyroid Nodules: Recommendations from the Asian Conference on Tumor Ablation Task Force - Secondary Publication

Radiofrequency ablation (RFA) is a thermal ablation technique widely used for the management of benign thyroid nodules. To date, five academic societies in various countries have reported clinical practice guidelines, opinion statements, or recommendations regarding the use of thyroid RFA. However, despite some similarities, there are also differences among the guidelines, and a consensus is required regarding safe and effective treatment in Asian countries. Therefore, a task force was organized by the guideline committee of the Asian Conference on Tumor Ablation with the goal of devising recommendations for the clinical use of thyroid RFA. The recommendations in this article are based on a comprehensive analysis of the current literature and the consensus opinion of the task force members.

Chemical ablation using ethanol or OK-432 for the treatment of thyroglossal duct cysts: a systematic review and meta-analysis

OBJECTIVES

To review the effectiveness and safety of chemical ablation using ethanol or OK-432 for the treatment of TGDCs (thyroglossal duct cysts).

METHODS

MEDLINE and EMBASE databases were searched up to May 29, 2020, to identify studies reporting the safety and efficacy of chemical ablation using ethanol or OK-432 for the treatment of TGDCs. The search query consisted of synonyms of thyroglossal duct cysts and ethanol or OK-432 ablation. The pooled success and complication rates were calculated using the inverse variance method to calculate weights, and pooled proportions were determined using the DerSimonian-Laird random-effects method.

RESULTS

Seven original articles including a total of 129 patients were included. The efficacy of chemical ablation was acceptable, with a pooled success rate of 70% (95% CI, 47-86%). The pooled success rate of ethanol ablation was superior to that of OK-432 ablation, although with equivocal statistical significance (84% vs. 51%, p = 0.055). Repeat ethanol ablation achieved a pooled success rate of 47% (95% CI, 24-71%). The chemical ablation procedures were safe, with a pooled major complication rate of 0.9% (95% CI, 0.1-5.8%).

CONCLUSIONS

Chemical ablation using ethanol or OK-432 for the treatment of TGDCs had acceptable success and low complication rates, and repeat treatment after initial failure was also feasible. In addition, it is an inexpensive and simple procedure and could therefore be considered a first-line treatment for TGDCs.

KEY POINTS

• The efficacy of chemical ablation using ethanol or OK-432 was acceptable, with a pooled success rate of 70% (95% CI, 47-86%). The pooled success rate of ethanol ablation was superior to that of OK-432 ablation, although with equivocal statistical significance (84% vs. 51%, p = 0.055). • Repeat ethanol ablation was also feasible, with a pooled success rate of 47% (95% CI, 24-71%). • The chemical ablation procedures were safe, with a pooled major complication rate of 0.9% (95% CI, 0.1-5.8%).

Ultrasound-Guided Radiofrequency Ablation Versus Surgical Resection for the Treatment of T1bN0M0 Papillary Thyroid Carcinoma in Different Age Groups

PURPOSE

We aimed to compare the efficacy and safety of radiofrequency ablation (RFA) to that of surgical resection (SR) in patients with T1bN0M0 papillary thyroid carcinoma (PTC) in different age groups.

METHODS

Totally, 204 patients with an isolated, solitary, intrathyroidal T1bN0M0 PTC, who underwent either RFA (n=94) or SR (n=110) between April 2014 and December 2019, were retrospectively enrolled and were divided into two subgroups according to age (<45 years, ≧45 years). Patients with pathologically aggressive or advanced lesions were excluded from the study. Tumor progression and procedural complications were the primary and secondary endpoints, respectively. Tumor recurrence in situ, newly discovered tumors, lymph node involvement, or distant metastases indicated tumor progression. Complications included pain, fever, voice change, choking, numbness in the limbs, and cardiac events. Incidence rates of all endpoint events were compared between different age subgroups.

RESULTS

There were no significant differences in age, sex, and tumor size between the treatment groups. While the RFA group incurred less cost and experienced significantly shorter operative duration than the SR group, no significant differences were observed in incidences of both tumor progression and complications. Further, subgroup analysis of patients <45 years versus those ≧45 years showed no significant differences in the incidence of tumor progression and complications within or between different treatment groups. Older patients in the SR group incurred higher hospital costs than younger counterparts, but this difference was not observed in the RFA group.

CONCLUSIONS

Our results indicated that RFA had a similar prognosis as that of SR but was associated with lower overall cost in both young (<45 years) and middle-aged patients (≧45 years) with T1bN0M0 PTC. Therefore, RFA may be an effective and safe alternative to surgery for the treatment of patients with T1bN0M0 PTC.

Radiofrequency ablation of benign thyroid nodules: recommendations from the Asian Conference on Tumor Ablation Task Force

Radiofrequency ablation (RFA) is a thermal ablation technique widely used for the management of benign thyroid nodules. To date, five academic societies in various countries have reported clinical practice guidelines, opinion statements, or recommendations regarding the use of thyroid RFA. However, despite some similarities, there are also differences among the guidelines, and a consensus is required regarding safe and effective treatment in Asian countries. Therefore, a task force was organized by the guideline committee of the Asian Conference on Tumor Ablation with the goal of devising recommendations for the clinical use of thyroid RFA. The recommendations in this article are based on a comprehensive analysis of the current literature and the consensus opinion of the task force members.