Radiofrequency ablation of benign non-functioning thyroid nodules: 4-year follow-up results for 111 patients

Adjustable-tip needles versus fixed-tip needles in radiofrequency ablation of symptomatic benign thyroid nodules: a single-center Italian experience

PURPOSE

In this retrospective, observational study we aim to compare the outcomes of the RFA treatment of benign thyroid nodules, carried out respectively with the standard fixed-needle approach (FTN) and the adjustable-tip needle technique (ATN), considered a more tailored, quicker and easier technical approach.

METHODS

We enrolled 36 patients who underwent RFA treatment of symptomatic, benign, thyroid nodule, 18 with the ATN and 18 with the FTN approach, respectively. Data about absolute volume reduction, volume reduction rate (VRR) and success rate (defined as VRR ≥ 50%), after 1, 3 and 6 months of follow-up were compared.

RESULTS

Our study suggested no substantial difference between the approaches, up to 6 months of follow-up, both in terms of absolute reduction (p = 0.27) and VRR (p = 0.14). These results were confirmed when the success rates, both in terms of 50%-reduction (p = 0.12) and absolute reduction (p = 0.42), was considered. Only at the 6-month evaluation, the FTN procedure showed a better success rate, yet without statistical significance (88.9% vs. 61.1%, p = 0.12). No difference emerged both in terms of patients' satisfaction and safety.

CONCLUSION

Our small experience suggested no substantial difference between ATN and FTN, in terms of outcomes. On the other hand, ATN was considered to be more straightforward and could consequently allow for a shorter operator learning curve.

Radiofrequency ablation of Bethesda category III thyroid nodules with benign molecular testing: Preliminary findings from a single institution

BACKGROUND

The efficacy of radiofrequency ablation (RFA) in treating thyroid nodules with indeterminate cytology remains less studied. The objective of this study was to determine the efficacy of RFA in treating nodules with Bethesda III that have been molecularly profiled benign (BIII-MPN).

METHODS

We included prospectively enrolled patients who underwent RFA for benign and BIII-MPN thyroid nodules. Primary outcome measures were volume reduction ratio (VRR), symptom score (range 0-10), and cosmetic score (range 0-3) at 1, 3, 6, and 12 months after RFA, as well as complication rates.

RESULTS

A total of 258 nodules in 192 patients were included (benign: 238 in 174; BIII-MPN: 20 in 18). The median VRR differed insignificantly, whereas symptom and cosmetic score improvements were similar between two cohorts. BIII-MPN thyroid nodules were associated with lower rates of infection and temporary voice change.

CONCLUSION

Our preliminary findings suggest that RFA may be a feasible management option for BIII-MPN thyroid nodules. However, appropriate will be important to address the important risk of potentially missed malignancies.

Efficacy and safety of laser ablation and microwave ablation to treat papillary thyroid microcarcinoma: A retrospective study

OBJECTIVE

To retrospectively analyze the efficacy and safety of laser ablation (LA) and microwave ablation (MWA) in the treatment of papillary thyroid microcarcinoma (PTMC).

METHODS

This was a retrospective study of 103 patients (109 nodules) who underwent thermal ablation for PTMC between October 2019 and March 2023; 61 underwent LA and 48 underwent MWA. The mean patients' age was 43.50 ± 12.42 years. After ablation, changes in tumor size at different time points, local recurrence, new lesions, lymph node metastasis, and complications were evaluated and recorded. The feasibility, success rate, and safety of LA and MWA were analyzed.

RESULTS

Complete absence of enhancement on contrast-enhanced ultrasonography was observed in all target tumors after ablation. At the last follow-up, the mean volume of the PTMC nodules decreased from 0.09 ± 0.09 to 0.03 ± 0.03 ml (LA group) and from 0.11 ± 0.10 to 0.06 ± 0.08 ml (MWA group) (both, P < 0.05). There was no significant difference in volume change between the groups (P (groups): 0.520; P (groups over time): 0.423), indicating similar efficacy between the groups. There was also no significant difference in the volume reduction rate between the groups during follow-up, except for at 3 months (P = 0.023). The complication rates did not differ between the LA group (8.2 %) and MWA group (6.3 %) (P > 0.05).

CONCLUSION

During the short-term follow-up, ultrasound-guided LA and MWA were effective and safe for PTMC, and there were no significant differences in treatment outcomes between the methods.

The Two-Year Results of Using Radiofrequency Ablation as a Novel Treatment for Persistent or Relapsed Graves' Disease: A Prospective Study

Objectives: Graves' disease (GD) is the most common cause of hyperthyroidism. Antithyroid drugs (ATDs) are the first-line treatment, but when discontinued, >50% of patients experience relapses. Conventional definitive treatment options include surgery and radioiodine therapy (RAI), each with its own disadvantages. Radiofrequency ablation (RFA) achieved promising short-term remission rates in a previous pilot study. The current study reports our experience of using RFA to treat relapsed GD in the largest cohort of patients with a longer follow-up period. Methods: This single-arm prospective study recruited consecutive patients aged ≥18 with persistent/relapsed GD requiring ATD from two tertiary endocrine surgery centers. Those with compressive goiter, suspected thyroid malignancy, moderate-to-severe Graves' ophthalmopathy, preference for surgery/RAI, or pregnancy were excluded. Eligible patients received ultrasound-guided RFA to the entire bulk of the thyroid gland. ATDs were discontinued afterward, and thyroid function tests were monitored bimonthly. The primary outcome was the disease remission rate at 24 months follow-up after single-session RFA, defined as being biochemically euthyroid or hypothyroid without ATD. Secondary outcomes were complication rates. Results: Of the 100 patients considered, 30 (30.0%) patients were eligible and received RFA. Most were female patients (93.3%). The median total thyroid volume was 23 mL (15.9-34.5). All completed 24 months follow-up. After single-session RFA, disease remission rates were 60.0% at 12 months and 56.7% at 24 months. Among the 13 patients with relapse after RFA, 9 (69%) required a lower ATD dose than before RFA; 2 received surgery without complications. Total thyroid volume was the only significant factor associated with relapse after RFA (odds ratio 1.054, confidence interval 1.012-1.099, p = 0.012). At 24 months, RFA led to disease remission in 100% of the 9 patients with a total thyroid volume <20 mL and 35% of patients with a total thyroid volume ≥20 mL (p = 0.007). There was no vocal cord palsy, skin burn, hematoma, or thyroid storm after RFA. Conclusions: In a highly selected group of patients with relapsed GD and predominantly small thyroid glands, single-session RFA may achieve disease remission. Smaller total thyroid volume may be a favorable factor associated with disease remission after RFA. The results of this study need to be confirmed with a long-term clinical trial. Clinical Trial Registration: This study is registered at www.clinicaltrial.gov with identifier NCT06418919.

Radiofrequency Ablation for the Treatment of Benign Thyroid Nodules: 10-Year Experience

Background: Longer follow-up after radiofrequency ablation (RFA) of benign thyroid nodules is needed to understand regrowth and other causes of delayed surgery and long-term complications. Methods: This retrospective study included consecutive patients treated with RFA for symptomatic benign nonfunctioning thyroid nodules between March 2007 and December 2010. RFA was performed according to the standard protocol. We followed up patients at 1, 6, and 12 months, then yearly, until August 2022, and calculated the volume reduction ratio (VRR) at each follow-up. We assessed the incidence of regrowth according to three published criteria, delayed surgery, and complications. The Kaplan-Meier method was used to evaluate the cumulative incidence of regrowth, and univariable and multivariable Cox regression analyses were performed to identify risk factors for regrowth. Results: This study included 421 patients (mean age, 47 ± 13 years; 372 women) with 456 nodules (mean volume, 21 ± 23 mL). The median follow-up period was 90 months (interquartile range, 24-143 months). The mean VRR was 81% at 2 years, 90% at 5 years, and 94% at ≥10 years. Overall regrowth was noted in 12% (53/456) of nodules and was treated with repeat RFA (n = 33) or surgery (n = 4) or left under observation (n = 16). Thyroid nodules with ≥20 mL initial volume had significantly higher risk of regrowth compared with nodules with <10 mL initial volume (hazard ratio, 2.315 [95% confidence interval, 1.183-4.530]; p = 0.014 on multivariable Cox regression analysis). Delayed surgery was performed in 6% (26/421) of patients because of regrowth and/or persistent symptoms (n = 4) or newly detected thyroid tumors (n = 22), one benign and 21 malignant. The overall complication rate was 2.4% (10/421), with no procedure-related deaths or long-term complications. Conclusion: RFA is safe and effective for treating benign thyroid nodules, with a high VRR at long-term follow-up. Regular follow-up after initial success is warranted because of the possibility of regrowth of ablated nodules and the need for delayed surgery in some patients.

The Role of Radiofrequency Ablation in Benign and Malignant Thyroid Nodules

Radiofrequency ablation (RFA) offers a minimally invasive solution for benign, autonomously functioning (AFTN), and malignant thyroid nodules. The technique utilizes high-frequency alternating current to induce coagulative necrosis, effectively destroying target tissue. RFA is performed in the outpatient setting with local anesthesia and sonographic guidance. RFA is effective in producing substantial volume reduction rates in benign nodules and is emerging as a favorable option in AFTN and papillary thyroid microcarcinoma. RFA's advantages include lower complication rates, minimal scarring, and improved quality-of-life outcomes compared to surgery. However, its efficacy in larger and recurrent malignancies requires further investigation.

The Influence of Impedance on the Efficacy of Radiofrequency Ablation for Benign Thyroid Nodules

OBJECTIVE

Radiofrequency ablation (RFA) uses the heat generated by a high-frequency alternating electric current, and according to Ohm's and Joule's law, the delivered current is inversely proportional to the circuit impedance. The primary objective of this study was to investigate whether tissue impedance during radiofrequency ablation (RFA) for benign thyroid nodules is related to the degree of volume reduction.

METHODS

This observational study included consecutive patients treated with RFA for benign thyroid nodules from February 2020 to August 2023. Technical effectiveness was defined as a volume reduction percentage (VRP) >75% at 6 months after the treatment. Multivariate logistic regression analyses were performed to identify the potential role of clinical factors and changes in tissue impedance on technique effectiveness.

RESULTS

Totally 72 patients were included with 73 benign thyroid nodules. Maximal impedance peaks reached <18 times, and mean procedural impedance ≤300 Ω were significantly associated with a volume decrease of >75% at bivariate analysis. These cutoff points were exploratory, as no existing literature suggests these variables are related to the degree of volume reduction. After adjusting for age, volume, and composition, significant associations were found for mean electrical impedance in the multivariate analysis (OR = 4.86 [confidence interval [CI] 1.29-18.26], p = 0.019). The energy adjusted by volume (delivered energy) was not associated with a VRP >75% (p = 0.7746).

CONCLUSIONS

This study suggests that a mean procedural impedance

LEVEL OF EVIDENCE

3 Laryngoscope, 2024.

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Key Words

• benign thyroid nodule
• impedance
• minimally invasive techniques
• radiofrequency ablation
• thermal ablation

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Affiliation(s)

Juan Pablo Dueñas Division of Endocrine Surgery, Integral Endocrine Surgery Clinic, Medellin, Colombia
Nathalia Buitrago-Gómez Department of Endocrinology, Universidad Pontificia Bolivariana, Medellin, Colombia
José Hugo Arias-Botero Medicine, CES University, Medellín, Colombia
Gregory Randolph Otolaryngology Head and Neck Surgery, Claire and John Bertucci Endowed Chair in Thyroid Surgical Oncology, Harvard Medical School, Chief Thyroid/Parathyroid Endocrine Surgical Division, Dept Otolaryngology Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Member Endocrine Surgical Service, Massachusetts General Hospital, President American Academy of Otolaryngology Head and Neck Surgery 2016-17, American Head and Neck Society, Administration Division Chair, International Thyroid Oncology Group (ITOG) President, American College of Surgeons Otolaryngology Governor, Boston, Massachusetts, U.S.A
Marika Russell Division of Thyroid and Parathyroid Endocrine Surgery, Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, U.S.A
Amr Abdelhamid Ahmed Division of Thyroid and Parathyroid Endocrine Surgery, Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, U.S.A
Roberto Valcavi Division of Endocrinology, The Endocrine & Thyroid Clinic (ETC), Reggio Emilia, Italy
Carlos Simón Duque Head and Neck Surgeon, Intermedica, Medellin, Colombia
Ralph P Tufano FPG Thyroid and Parathyroid Center, Sarasota Memorial Health Care System, Sarasota, Florida, U.S.A

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Comparative efficacy and safety of radiofrequency ablation and microwave ablation in benign thyroid nodule treatment: a systematic review and meta-analysis

OBJECTIVE

Ultrasound-guided thermal ablation, including radiofrequency ablation (RFA) and microwave ablation (MWA), has become one of the main options for treating benign thyroid nodules (BTNs). To assess the efficacy of thermal ablation of BTNs, we performed a systematic review and meta-analysis of relevant studies.

MATERIALS AND METHODS

A comprehensive search of MEDLINE, EMBASE, and COCHRANE databases was performed up to September 25, 2023, to identify studies directly comparing RFA and MWA for pathologically proven BTNs and reporting clinical outcomes and complications. Data extraction and quality assessment were independently performed by two radiologists according to PRISMA guidelines. The analysis yielded the serial volume reduction ratios (VRRs) of ablated nodules for up to 12 months, symptom and cosmetic scores, and complications.

RESULTS

This analysis included nine studies with 1305 BTNs treated by RFA and 1276 by MWA. VRRs at 1 month, 3 months, and 6 months were similar between RFA and MWA, but RFA showed a significantly higher VRR (83.3%) than MWA (76.9%) at 12 months (p = 0.02). Complication rates showed no significant difference between the two methods. Symptom and cosmetic scores significantly decreased after ablation, without a significant difference between the methods. Subgroup analysis indicated a significantly higher VRR at 12 months for RFA than for MWA for less experienced investigators (≤ 10 years), but no significant difference for more experienced investigators (> 10 years).

CONCLUSION

RFA and MWA are both effective and safe methods for treating BTNs. RFA showed a higher VRR at 12 months and seems more suitable for less experienced investigators.

CLINICAL RELEVANCE STATEMENT

RFA and MWA are both effective and safe treatments for BTNs, with RFA showing a higher VRR at 12 months. Both methods offer minimally invasive and reliable treatment for thyroid nodules.

KEY POINTS

The most effective thermal ablation technique for BTNs remains undetermined. RFA showed a higher VRR at 12 months than MWA. Both techniques are effective for treating thyroid nodules; RFA offers greater benefits, particularly for less experienced investigators.

Long-term outcomes of radiofrequency ablation for intrathoracic goiter up to 5 years: evaluated by computed tomography/magnetic resonance imaging and ultrasound

OBJECTIVES

This study evaluated the long-term efficacy and safety of radiofrequency ablation (RFA) for intrathoracic goiter (ITG) over a follow-up period exceeding six months.

METHODS

From 2017 to 2022, 22 patients (6 males, 16 females) with 24 ITGs treated with RFA at a single medical center were evaluated. All patients underwent ultrasonography (US), computed tomography (CT), or magnetic resonance imaging (MRI) before RFA. Follow-up CT/MRI was performed six months after the initial RFA and then every 6-12 months. The primary outcomes measured were the degree of extension, goiter volume, volume reduction rate (VRR), tracheal deviation, and tracheal lumen. Additionally, we assessed the outcomes of single-session RFA (n = 16) vs. multiple sessions (n = 8) on goiters and explored the correlation between ITG volume measurements obtained using ultrasonography and CT/MRI.

RESULTS

The median follow-up period was 12 months (interquartile range: 6-36.8 months). At the last follow-up, the nodule volume measured by CT/MRI had significantly decreased (76.2 vs. 24.6 mL; p < 0.05), with a VRR of 64.6%. Patients who underwent multiple RFA sessions showed a significantly higher VRR than the single-session patients (63.8 vs. 80.1%, p < 0.05). The intraclass correlation between goiter volumes measured using US and CT/MRI was moderate.

CONCLUSION

This study affirms the long-term efficacy and safety of RFA for ITG, providing an alternative treatment for nonsurgical candidates. Multiple RFA sessions may be beneficial for achieving better volume reduction. Sole reliance on ultrasonography is inadequate; therefore, integrating CT/MRI is essential for accurate pre-RFA and follow-up assessments.

Effect of different retention doses of ultrasound-guided polidocanol chemical ablation for benign cystic-solid thyroid nodules

OBJECTIVE

To assess the influence of varying retention doses of ultrasound-guided polidocanol chemical ablation for benign cystic-solid thyroid nodules.

METHODS

A retrospective study was conducted from December 2019 to January 2022, including 78 patients with benign cystic-solid thyroid nodules, of which 31 received polidocanol chemical ablation alone, 23 received polidocanol chemical plus thermal ablation, and 24 received open surgery. Patients who received polidocanol chemical ablation were assigned into groups based on the retention dose of polidocanol: 0 %, 10 %, 20 %, 30 %, and 50 %. Follow-ups were done at 1, 3, 6, and 12 months postoperatively. The volume of the nodules, postoperative complications, and recurrence of the nodules were examined before treatment and during follow-up visits.

RESULTS

Total operation time and intraoperative bleeding volume for patients who received ablation were substantially lower than those for patients who received open surgery (P < 0.001). Among patients in the polidocanol chemical ablation group, volume shrinkage rate of thyroid nodules in the 10 % retention dose group was significantly lower than that in the 0 % retention dose group at 1, 3, and 6 months postoperatively (P < 0.05). The 30 % retention dose group had the highest nodule shrinkage rate (98.46 ± 1.55 %) at 12 months postoperatively, which was significantly higher than that in the 50 % retention dose group (P < 0.05). Among patients in the polidocanol chemical and thermal ablation group, the volume shrinkage rate of thyroid nodules in the 10 % and 30 % retention dose groups at 1 month postoperatively was significantly lower than that in the 0 % retention dose group (P < 0.05). Although volume shrinkage rate in the 20 % retention dose group after thermal ablation was higher than that in the 0 % retention dose group, the difference was not statistically significant (P > 0.05). In terms of adverse reactions, the incidence of hoarseness and coughing was higher in the open surgery group than in the polidocanol chemical ablation and polidocanol chemical and thermal ablation groups, but there was no significant difference (P > 0.05).

CONCLUSION

Chemical ablation with polidocanol was safe and effective for therapy of benign cystic-solid thyroid nodules, and the optimal retention dose may be between 20 % and 30 %. Patients with poor efficacy from chemical ablation alone can receive safe and effective treatment through thermal ablation.

A 6-year single-center prospective follow-up study of the efficacy of radiofrequency ablation for thyroid nodules

Background

Radiofrequency ablation (RFA) is an alternative modality for thyroid nodules (TNs) and many studies have also confirmed its favorable efficacy and safety. The scope of RFA increases in clinical practice and the aim of our study was to evaluate the efficacy of RFA.

Methods

We conducted a prospective study to evaluate the efficacy of RFA for thyroid nodules between January 2017 and December 2022 at our institution. We assessed the change in nodal volume, volume reduction ratio (VRR), technique effective (TE) rate, complete ablation (CA) rate, and nodal regrowth rate and time after RFA.

Results

We performed RFA for 1703 patients with TNs between January 2017 and December 2022, of which a total of 970 eligible patients were enrolled in the study. The preoperative volume of TNs was 6.23 ± 8.11ml, with 821 benign and 149 malignant nodules. The post-RFA TE and adjusted TE rate were 80% and 88.8%, respectively. CA was achieved in 145 (14.9%) patients with a mean time of 18.32± 12.98 months; nodal regrowth occurred in 15 (1.5%) patients with a mean time of 29.80 ± 12.47 months. TNs volume and VRR changed significantly at years 1 and 2 after RFA and stabilized after 5 years. A serious postoperative adverse event occurred in one patient with cervical sympathetic chain injury resulting in Horner's syndrome. A transient or permanent damage of the recurrent laryngeal nerve could not be evaluated due to the lack of postoperative laryngoscopy, and this is a significant limitation of the study.

Conclusion

The expanded RFA indications were also effective for TNs, with no significant change in long-term efficacy.

The Comparison of Efficacy and Safety between Radiofrequency Ablation Alone and Ethanol Ablation Followed by Radiofrequency Ablation in the Treatment of Mixed Cystic and Solid Thyroid Nodule

Purpose

To compare the efficacy and safety of radiofrequency ablation (RFA) and ethanol ablation (EA) followed by RFA in treating mixed cystic and solid thyroid nodules.

Materials and Methods

We included 243 nodules from 243 patients who underwent RFA for mixed cystic and solid benign nodules. The nodules were divided into two groups (RFA alone and EA + RFA). We evaluated volume reduction rate (VRR), therapeutic success rate, improvement in symptomatic and cosmetic issues, complications, and adverse effects.

Results

The RFA group included 204 patients, and the EA + RFA group included 39 patients. The long-term success rates in the RFA only and EA + RFA groups were 90.2% and 97.4%, respectively. The mean VRR at the last follow-up in the RFA and EA + RFA groups were 81.6% and 87.2%, respectively. Therapeutic results were similar in both groups at the last follow-up. Cosmetic and symptomatic problems markedly improved in both groups. No major complications were observed.

Conclusion

Both RFA alone and EA + RA are safe and effective methods for treating mixed cystic and solid thyroid nodules, although EA + RFA is slightly more effective.

Clinical Outcomes of Thermal Ablation Re-Treatment of Benign Thyroid Nodules: A Multicenter Study from the Italian Minimally Invasive Treatments of the Thyroid Group

Background: Thermal ablation (TA) is an established therapeutic option alternative to surgery in patients with solid benign thyroid nodules causing local symptoms. However, a variable part of thyroid nodules remain viable after these nonsurgical treatments, and as many as 15% of nodules treated with TA may require a second treatment over time. This study aimed to evaluate the outcomes of TA re-treatment on symptomatic benign thyroid nodules where the volume decreased by <50% after the first procedure ( = technique inefficacy). Methods: We performed a multicenter retrospective cohort study including patients who underwent re-treatment with TA for benign thyroid nodules, whose volume decreased by <50% after initial treatment. The primary aim was to evaluate volume and volume reduction ratio (VRR) over time and compare the 6- and 12-month VRR after first versus second treatment. The secondary aim was to identify protective or risk factors for technique inefficacy, regrowth, and further treatments, expressed as adjusted hazard ratios (HRs) and confidence interval [CI], after adjustment for sex, age, nodule volume, structure and function, nodule regrowth or symptom relapse, technique used and if the same technique was used for the first and second TA and time between them. Results: We included 135 patients. Re-treatment led to VRR of 50% and 52.2% after 6 and 12 months. VRR after re-treatment was greater than after first treatment in small and medium size nodules (<30 mL), while there were no differences for large nodules (>30 mL). After re-treatment technique inefficacy rate was 51.9%, regrowth rate was 12.6%, and further treatment rate was 15.6%. Radiofrequency ablation (RFA) was protective toward technique inefficacy (HR = 0.40 [CI 0.24-0.65]) and need of further treatments (HR = 0.30 [CI 0.12-0.76]). Large nodule volume (>30 mL) was associated with increased risk of re-treatment (HR = 4.52 [CI 1.38-14.82]). Conclusions: This is the first study evaluating the outcomes of re-treatment on symptomatic benign thyroid nodules with a VRR <50% after the initial TA treatment. Best results were seen in small and medium nodules (<30 mL) and after RFA. Prospective confirmatory studies are needed.

Comparison of the Therapeutic Efficacy and Technical Outcomes between Conventional Fixed Electrodes and Adjustable Electrodes in the Radiofrequency Ablation of Benign Thyroid Nodules

OBJECTIVE

This study aimed to compare therapeutic efficacy and technical outcomes between adjustable electrode (AE) and conventional fixed electrode (FE) for radiofrequency ablation (RFA) of benign thyroid nodules.

MATERIALS AND METHODS

Between 2013 and 2021, RFA was performed on histologically proven benign thyroid nodules. For the AE method, AE length ≥ 1 cm with higher power and < 1 cm with lower power were utilized for ablating feeding vessels and nodules, especially those near anatomical structures, respectively. The therapeutic efficacy (volume reduction rate [VRR], complication rate, and regrowth rate) and technical outcomes (total energy delivery, ablated volume/energy, RFA time, and ablated volume/time) of FE and AE were compared. Continuous parameters were compared using a two-sample t-test or Mann-Whitney U test, and categorical parameters were compared using a chi-squared test or Fisher's exact test.

RESULTS

A total of 182 nodules (FE: 92 vs. AE: 90) in 173 patients (mean age ± standard deviation, 47.0 ± 14.7 years; female, 90.8% [157/173]; median follow-up, 726 days [interquartile range, 441-1075 days]) were analyzed. The therapeutic efficacy was comparable, whereas technical outcomes were more favorable for AE. Both electrodes demonstrated comparable overall median VRR (FE: 92.4% vs. AE: 84.9%, P = 0.240) without immediate major complications. Overall regrowth rates were comparable between the two groups (FE: 2.2% [2/90] vs. AE: 1.1% [1/90], P > 0.99). AE demonstrated a shorter median RFA time (FE: 811 vs. AE: 627 seconds, P = 0.009). Both delivered comparable median energy (FE: 42.8 vs. AE: 29.2 kJ, P = 0.069), but AE demonstrated higher median ablated volume/energy and median ablated volume/time (FE: 0.2 vs. AE: 0.3 cc/kJ, P < 0.001; and FE: 0.7 vs. AE: 1.0 cc/min, P < 0.001, respectively).

CONCLUSION

Therapeutic efficacy between FE and AE was comparable. AE demonstrated better technical outcomes than FE in terms of RFA time, ablated volume/energy, and ablated volume/time.

The safety and efficacy of radiofrequency ablation in benign pediatric thyroid disease in the US: An initial case series

Objective

To evaluate the efficacy and safety of radiofrequency ablation (RFA) for benign nonfunctional thyroid nodules or functional lingual thyroid gland in a pediatric population.

Methods

Four pediatric patients (four female; mean age 13.50 ± 4.04, range 8-17 years) with either benign thyroid nodules or mildly obstructive lingual thyroid glands were treated with RFA from 2020 to 2021 were evaluated. The inclusion criteria for RFA therapy were (i) age < 18 years; (ii) benign cytopathological results on ultrasound guided fine needle aspiration; (iii) pressure or pain symptoms caused by the thyroid nodules; (iv) dysphagia or obstruction caused by the lingual thyroid tissue; (v) follow up for >6 months with otolaryngology or endocrinology.

Results

Two patients had benign non-functioning thyroid nodules and two had mildly obstructive functioning lingual thyroid glands. Mean follow up was 10.75 ± 4.79 months. Each patient underwent one RFA session with no complications. For the patients with thyroid nodules, there was >74% reduction in nodule size at last follow up with improvement in neck swelling and pain. For the patients with lingual thyroid glands, both did not have any other functional thyroid gland identified. Both had visible decrease in size of the gland as visualized transorally with improvement in dysphagia and obstructive symptoms when lying flat.

Conclusion

RFA is a safe and effective option for managing benign thyroid nodules and lingual thyroid glands in a pediatric patient population.

Level of evidence

4.

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.

Radiofrequency ablation of benign thyroid nodules: A prospective, multi-institutional North American experience

BACKGROUND

Radiofrequency ablation for benign thyroid nodules aims to achieve a volume reduction rate of ≥50%. However, factors that predict treatment success have not been defined in a large-scale study.

METHODS

A prospective cohort study of biopsy-proven benign thyroid nodules treated with radiofrequency ablation at 3 institutions was performed. Patient demographics, nodule sonographic features, procedural data, and nodule volume reduction were evaluated. Binary logistic regression analysis was performed to identify features associated with treatment response.

RESULTS

A total of 620 nodules were analyzed. The pooled median volume reduction rate at 12 months was 70.9% (interquartile range 52.9-86.6). At 1 year follow-up, 78.4% of nodules reached treatment success with a volume reduction rate ≥50%. The overall complication rate was 3.2% and included temporary voice changes (n = 14), vasovagal episodes (n = 5), nodule rupture (n = 3), and lightheadedness (n = 2). No permanent voice changes occurred. Four patients developed postprocedural hypothyroidism. Large baseline nodule volume (>20 mL) was associated with a lower rate of successful volume reduction (odds ratio 0.60 [0.37-0.976]). Large nodules achieved treatment success by 12-month follow-up at a rate of 64.5%, compared with 81.4% for small nodules and 87.2% for medium nodules.

CONCLUSION

To our knowledge, this is the largest North American cohort of patients with benign thyroid nodules treated with radiofrequency ablation. Overall, radiofrequency ablation was an effective treatment option with a low risk of procedural complications. Large volume nodules (>20 mL) may be associated with a lower rate of successful reduction with radiofrequency ablation treatment.

Five-year follow-up results of thermal ablation for benign thyroid nodules: Systematic review and meta-analysis

OBJECTIVES

Confidence in long-term treatment results of thermal ablation for benign thyroid nodules (BTNs) is required in comparison with surgery. The objective of this meta-analysis is to report 5-year follow-up results of thermal ablation for BTNs.

METHODS

Ovid PUBMED, COCHRANE, and EMBASE databases were searched through Feb 30, 2023, for studies reporting outcomes in patients with BTNs treated with thermal ablation and followed up for about 5 years. Pooled volume reduction rates (VRRs) at 6, 12, 24, 36, 48, and 60 months after thermal ablation were assessed. Data were extracted and methodological quality was assessed independently by two radiologists according to the PRISMA guidelines.

RESULTS

Five studies, involving 939 patients, met the inclusion criteria through database searches. 137 patients experienced local nodules recurrence during a mean pooled 59.25-month follow-up. Seventeen of them proved to be non-benign. Fifty of all patients with nodules regrowth had a secondary surgery, while 35 had a secondary thermal ablation. The pooled mean major complication rate was 7.70 %, with no patient experiencing life-threatening or delayed complications.

CONCLUSIONS

Thermal ablation is an excellent local nodules control method in patients with BTNs, and results in a clinically significant and long-lasting volume reduction of BTNs. The risk of regrowth and needing retreatment was lower after thermal ablation.

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.

Factors Influencing a Favorable Outcome for RFA of Huge Benign Thyroid Nodules: Preliminary Results and Short-Term Evaluation

Objective

This study aimed to investigate potentially favorable factors influencing the therapeutic success of radiofrequency ablation (RFA) of huge benign thyroid nodules (BTNs) (volume >100 ml) and to evaluate the feasibility of RFA as an alternative treatment modality for patients unable or unwilling to undergo surgery.

Methods

This retrospective study evaluated a total of 868 patients, of which 22 patients had huge BTNs who underwent ultrasound-guided moving shot RFA treatment between May 2017 and January 2022. The huge BTNs were categorized into two groups according to a post-RFA treatment volume reduction ratio (VRR) of >80% and <80% at 6 months. Factors influencing these huge BTNs were reviewed, analyzed, and correlated with treatment effectiveness between the two groups.

Results

The factors influencing an effective VRR included huge BTNs located on the left side (OR 7.875, p = 0.03), predominant solid/spongiform nodules (OR 7.875, p = 0.03), and higher initial ablation rate (IAR) (p = 0.028). Multivariable logistic regression revealed predominant solid/spongiform nodule and the higher IAR were associated with the advanced VRR.

Conclusion

RFA was effective at decreasing the volume of huge BTNs with an acceptable complication rate. The BTN characteristics correlated with a better VRR at the 6-month short-term follow-up were predominant solid/spongiform BTNs and those with the first time ablation treatment initial ablation rate. Nevertheless, regarding the higher regrowth rate of these groups of patients who may need to be treated more times, RFA can only be a feasible alternative treatment modality for patients unable or unwilling to undergo operation.

Heat sink effects in thyroid bipolar radiofrequency ablation: an ex vivo study

The study aimed to investigate heat sink effects in radiofrequency ablation (RFA) under thyroid-specific conditions. In an ex vivo model, bovine thyroid lobes were ablated using bipolar RFA with 2.0 kJ energy input at a power level set to 10 W (n = 35) and 25 W (n = 35). Glass vessels (3.0 mm outer diameter) placed within the ablation zone were used to deliver tissue perfusion at various flow rates (0, 0.25, 0.5, 1, 5, 10, 20 ml/min). Temperature was measured in the proximity of the vessel (Tv) and in the non-perfused contralateral region of the ablation zone (Tc), at equal distances to the ablation electrode (d = 8 mm). Maximum temperature within the perfused zone was significantly lowered with Tv ranging from 54.1 ± 1.5 °C (20 ml/min) to 56.9 ± 1.5 °C (0.25 ml/min), compared to Tc from 63.2 ± 3.5 °C (20 ml/min) to 63.2 ± 2.6 °C (0.25 ml/min) (10 W group). The cross-sectional ablation zone area decreased with increasing flow rates from 184 ± 12 mm2 (0 ml/min) to 141 ± 20 mm2 (20 ml/min) at 10 W, and from 207 ± 22 mm2 (0 ml/min) to 158 ± 31 mm2 (20 ml/min) in the 25 W group. Significant heat sink effects were observed under thyroid-specific conditions even at flow rates ≤ 1 ml/min. In thyroid nodules with prominent vasculature, heat dissipation through perfusion may therefore result in clinically relevant limitations to ablation efficacy.

Comparison of microwave alone and combined with ethanol ablation for different types of benign mixed thyroid nodules

OBJECTIVE

To evaluate the efficacy and safety of microwave ablation (MWA) plus ethanol ablation (EA) for different types of benign mixed thyroid nodules.

METHODS

A total of 81 patients with 81 benign mixed thyroid nodules were enrolled into the study; 39 were divided to the MWA group and 42 to the combined group (MWA combined with EA). Nodule ablation rate, volume reduction rate (VRR) and surgical complications of all patients were analyzed before and after treatment.

RESULTS

The mean ablation rate were 86.49 ± 6.68% and 90.09 ± 5.79% in the microwave and combined groups respectively, and the ablation rate of nodule decreased as the nodule volume increased. For nodules ≥15 ml in volume, the mean ablation rate of the combined group was higher than that of the microwave group (all P < 0.05). The mean VRR at 12 months postoperatively was 89.58 ± 4.32% in the microwave group and 92.92 ± 3.49% in the combined group, showing statistical significantly different between both arms (P = 0.001). The combined group decreased in volume more significantly than the microwave group for nodules with 20-50% or 50-80% cystic proportions or >15 ml in volume (all P < 0.05). The complication rate was 23.08% and 2.38% respectively.

CONCLUSION

MWA combined with EA is more effective than MWA for treating mixed thyroid nodules. MWA combined with EA may be the first approach for nodules with >20% cystic proportions or volume >15 ml.

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.

[Clinical Approach for Thyroid Radiofrequency Ablation]

Radiofrequency ablation (RFA) is a non-surgical treatment for symptomatic, benign thyroid nodules. This treatment works by heating and destroying the nodule tissue, which results in reduction of its size and alleviation of the symptoms involved. RFA is indicated for nodules which are confirmed to be benign on two or more cytological or histological examinations, and which result in clinical symptoms requiring medical treatment. It is associated with good short-term outcomes on one-year follow-up; however, 20%-30% of the nodules regrow after more than three years. Therefore, on the basis of long-term follow-up, management of regrowth is key to patient care following RFA. Regrowth is more likely to occur in nodules that are large in size prior to RFA, and in those with high or increased vascularity. Recently, new techniques such as hydrodissection, artery-first ablation, and venous ablation have been introduced to inhibit regrowth. In addition, appropriate criteria for additional RFA should be applied to manage regrowth and prolong its therapeutic effects. RFA is essentially an alternative to surgery; therefore, the ultimate goal of this procedure is to avoid surgery permanently, rather than to achieve temporary effects.

Can Thyroid Nodules be Managed with Radiofrequency Ablation?

Radiofrequency ablation (RFA) is an established and growing minimally-invasive technique with an impressive safety profile used to manage thyroid nodules. Beyond shorter operative and recovery times, the main advantages of RFA include the lack of an incisional scar as well as maximizing the potential for maintenance of normal thyroid function. RFA can significantly reduce nodular volume, achieving rates of 60% to 95% in a breadth of thyroid disease, including benign nodules, primary carcinomas, and recurrent malignancies. Thorough patient counselling is imperative for RFA candidates, including a discussant of complications, nodule regrowth, and the potential for a subsequent ablation session.

[Effective and Safe Application of Radiofrequency Ablation for Benign Thyroid Nodules]

Radiofrequency ablation (RFA) has been a representative, non-surgical treatment for benign thyroid nodules that cause cosmetic problems or compression symptoms. The procedure of RFA should be performed effectively and safely. This review discusses the patient selection, pre-procedure evaluation and planning, principles, devices, techniques, and complications with reference to the guidelines and research on thyroid RFA. In particular, this review will devote to introduce RFA techniques and to provide practical help in the implementation of this procedure.

Delayed Cancer Diagnosis in Thyroid Nodules Initially Treated as Benign With Radiofrequency Ablation: Ultrasound Characteristics and Predictors for Cancer

OBJECTIVE

Regrowth after radiofrequency ablation (RFA) of symptomatic large thyroid nodules, initially treated as benign, sometimes turns out to be malignancies. This study aimed to assess the ultrasound (US) characteristics of thyroid nodules initially treated as benign with RFA and later diagnosed as cancers, predictive factors for cancers masquerading as benign, and methods to avoid RFA in these cancers.

MATERIALS AND METHODS

We reviewed the medical records of 134 consecutive patients with 148 nodules who underwent RFA between February 2008 and November 2016 for the debulking of symptomatic thyroid nodules diagnosed as benign using US-guided biopsy. We investigated the pre-RFA characteristics of the thyroid nodules, changes at follow-up after RFA, and the final surgical pathology.

RESULTS

Nodule regrowth after RFA was observed in 36 (24.3%) of the 148 benign nodules. Twenty-two of the 36 nodules were surgically removed, and malignancies were confirmed in seven (19.4% of 36). Of the 22 nodules removed surgically, pre-RFA median volume (range) was significantly larger for malignant nodules than for benign nodules: 22.4 (13.9-84.5) vs. 13.4 (7.3-16.8) mL (P = 0.04). There was no significant difference in the regrowth interval between benign and malignant nodules (P = 0.49). The median volume reduction rate (range) at 12 months was significantly lower for malignant nodules than for benign nodules (51.4% [0-57.8] vs. 83.8% [47.9-89.6]) (P = 0.01). The pre-RFA benignity of all seven malignant nodules was confirmed using two US-guided fine-needle aspirations (FNAs), except for one nodule, which was confirmed using US-guided core-needle biopsy (CNB). Regrown malignant nodules were diagnosed as suspicious follicular neoplasms by CNB. Histological examination of the malignant nodules revealed follicular thyroid carcinomas, except for one follicular variant, a papillary thyroid carcinoma.

CONCLUSION

Symptomatic large benign thyroid nodules showing regrowth or suboptimal reduction after RFA may have malignant potential. The confirmation of these nodules is better with CNB than with FNA.

Minimally Invasive Treatments of Benign Thyroid Nodules: A Network Meta-Analysis of Short-Term Outcomes

Background: Image-guided thermal ablation interventions are novel thermal-based modalities used for the treatment of benign thyroid nodules. Methods: We conducted a systematic review and a Bayesian network meta-analysis, examining studies using thermal ablation interventions in the treatment of benign nodular thyroid disease (PROSPERO CRD42022367680). The primary endpoints included volume reduction rate (VRR), and symptomatic score and cosmetic score improvement. Secondary endpoints included vocal disturbances, laryngeal nerve palsy, hypothyroidism, and nodular regrowth (defined by increased nodular volume of >50% for thermal ablation or new nodules arising in remaining thyroid tissue conventional surgery [CS]). Results: We included 16 studies (3 randomized controlled trials [RCTs] and 13 comparative case series), describing radiofrequency ablation (RFA), laser ablation (LA), microwave ablation (MWA), high-intensity focus ultrasound (HIFU), and CS, respectively. The review included data from 4112 patients followed for a mean of 11.9 months. Meta-analyses showed no significant differences among RFA, LA, MWA, HIFU, and CS regarding any of the primary endpoints of VRR, symptomatic score, and cosmetic score. In examining the surface under the cumulative ranking area (SUCRA) ranking, CS (SUCRA, 98.49), LA (SUCRA, 51.58), and MWA (SUCRA, 57.0) were identified as the three interventions that were most likely to result in the largest VRR, symptomatic and cosmetic score reduction. RFA, relative risk (RR) 0.19 [95% credibility interval (CI): 0.06 to 0.48], LA RR 0.23 [CI: 0.06 to 0.79], and MWA RR 0.25 [CI: 0.09 to 0.60] were associated with the greatest reduction in risk for postintervention vocal complications compared with CS, with RFA (SUCRA, 61.62) being ranked as the highest in safety. RFA RR 0.05 [CI: 0.00 to 0.40] and MWA RR 0.16 [CI: 0.02 to 0.73] were associated with a reduced risk of transient laryngeal nerve injury compared with CS. RFA RR 0.00 [CI: 0.00 to 0.00] and MWA RR 0.00 [CI: 0.00 to 0.03] were associated with a reduced risk of hypothyroidism occurrence compared with CS, with RFA (SUCRA, 99.86) yielding the highest safety ranking. RFA was associated with a reduced risk for nodular regrowth RR 0.09 [CI: 0.00 to 0.85], compared with CS. Conclusion: We have comprehensively reviewed the published literature on the efficacy and safety of thermal ablation modalities for benign thyroid nodules. Important research gaps remain regarding a paucity of both long-term data and high-quality RCTs.

Choice in Ablative Therapies for Thyroid Nodules

Ultrasound-guided ablation procedures have been growing in popularity and offer many advantages compared with traditional surgery for thyroid nodules. Many technologies are available, with thermal ablative techniques being the most popular currently though other nonthermal techniques, such as cryoablation and electroporation, are gaining interest. The objective of the present review is to provide an overview of each of the currently available ablative therapies and their applications in various clinical indications.

Analysis of 5 years' experience of a head and neck surgeon with radiofrequency ablation for benign thyroid nodule

PURPOSE

This study reports the long-term efficacy, safety, complications and management of radiofrequency ablation (RFA) for benign thyroid nodule performed over 5 years by a head and neck surgeon.

MATERIALS AND METHODS

We studied 287 consecutive patients who underwent RFA between March 2011 and January 2021. Pre- and postoperative thyroid nodule volumes were measured and volume reduction rate was calculated using ultrasonography (USG). Subjective symptom scores and cosmetic scores were investigated. Complications and their managements were analyzed. Complications and their management were investigated. Follow-up USG was performed at 6 and 12 months after RFA, and annually thereafter.

RESULTS

The mean volume reduction was 75.2 ± 23.8 % after 6 months and 91.9 ± 14.8 % after 5 years. All of nodule volume, and the cosmetic and symptom scores, decreased significantly postoperatively, and these scores were maintained to 5 years. Minor complications occurred in 15 of 287 (5.2 %) patients; there were no major complications. Injection laryngoplasty was performed for three patients with vocal cord paralysis. Two patients underwent open thyroid surgery because of nodule regrowth.

CONCLUSIONS

RFA is a safe and effective treatment without major complication for more than five years. Minor complications were managed by the head-and-neck surgeon personally.

Immunocytochemistry Profile of Benign Thyroid Nodules Not Responding to Thermal Ablation: A Retrospective Study

Purpose

Thermal ablations (TA) are gaining ground as alternative options to conventional therapies for symptomatic benign thyroid nodules. Little is known about the impact of nodule biology on the outcomes of TA. The aim of our study was to evaluate the baseline immunocytochemistry profile of thyroid nodules that were poorly responsive to TA in order to identify potential predictors of the treatment response.

Methods

From a cohort of 406 patients with benign thyroid nodules treated with TA and followed for 5 years, we retrospectively selected two groups of patients: NONRESPONDERS (patients who did not respond to TA and were later surgically treated) and RESPONDERS (patients who responded to TA). The fine-needle aspiration cytology (FNAC) slides obtained before TA were stained for Galectin-3, HBME-1, CK-19, and Ki-67.

Results

Benign nodules of NONRESPONDERS (n = 19) did not express CK-19 (p = 0.03), as compared to RESPONDERS (n = 26). We combined the absence of CK-19 and the presence of Ki-67 to obtain a composite biomarker of resistance to TA, which discriminated between likelihood of retreatment and no retreatment with an AUC of 0.68 (95%CI: 0.55-0.81) and a sensitivity, specificity, PPV, and NPV of 29%, 91%, 71%, and 64%, respectively.

Conclusion

In benign thyroid nodules, the absence of CK-19 was associated with resistance to TA, while the presence of CK-19 was predictive of response to TA. If confirmed, this finding could provide rapid and inexpensive information about the potential outcome of TA on benign thyroid nodules. In addition, as CK-19 can be expressed in adenomatous hyperplasia, it could be speculated that these nodules, rather than follicular adenomas, might be better candidates for TA.

Radiofrequency Ablation for Benign Thyroid Nodules: Radiology In Training

Two patients, one with benign nonfunctioning nodules and one with functioning thyroid nodules, both of whom underwent radiofrequency ablation, are presented. Preprocedural evaluation, procedural considerations, and follow-up care of thyroid radiofrequency ablation, as well as published evidence on the topic, are discussed.

Development and validation of a nomogram model for predicting residue of partially cystic thyroid nodules after ultrasound-guided ethanol and thermal ablation

OBJECTIVES

To develop and validate a nomogram model for predicting residue of partially cystic thyroid nodules (PCTNs) after ethanol and thermal ablation.

MATERIALS AND METHODS

From July 2015 to August 2022, a total of 97 patients (age 40.78 ± 12.61 years) with 107 treated benign PCTNs receiving ethanol and thermal ablation were enrolled. Pre-ablative laboratory test results and the ultrasound (US) and contrast-enhanced ultrasound (CEUS) features of lesions were collected. They were categorized into non-residue group and residue group according to the CEUS examination assessment after ablation. Univariate and multivariate logistic regression analysis were adopted to build a nomogram. The nomogram was validated by internal stratified fivefold cross-validation. The calibration, discrimination and clinical utility of the nomogram were investigated to assess the performance of the model.

RESULTS

Residue was reported in 30 out of 107nodules (28.0%). Multivariate logistic regression analysis revealed initial volume (OR=1.12, 95%CI 1.06-1.19) and presence of septum (OR=3.19, 95%CI 1.09-9.36) were predictors of residue of PCTNs. The nomogram developed by the above factors showed good calibration and discrimination. The area under the curve (AUC), sensitivity and specificity of this model were 0.832, 86.7% and 68.8%, respectively. When applied to internal validation, the model revealed good generalizability with stratified fivefold cross-validation in the cohort (mean AUC = 0.821).

CONCLUSIONS

The nomogram model has good performance for predicting the residue of PCTNs undergoing ethanol and thermal ablation. This could play a role in the decision of treatment and follow-up in clinical practice.

Initial ablation radio predicting volume reduction from microwave ablation of benign thyroid nodules

OBJECTIVE

Our research sought to investigate the relationship between initial ablation ratio (IAR) and internal composition of benign thyroid nodules treated by microwave ablation (MWA).

MATERIALS AND METHODS

Patients who underwent MWA at the Affiliated Hospital of Jiangsu University from January 2018 to December 2022 were enrolled in our research. All the patients were followed up for at least one year. We analyzed the relationship between IAR at 1 month of solid nodules (solid >90%), predominantly solid nodules (90% >solid > 75%), mixed solid alongside cystic nodules (75% >solid > 50%) as well as volume reduction rate (VRR) at 1, 3, 6 and 12 months follow-up.

OBJECTIVE

The mean IAR of the solid nodules (solid >90%) was 94.32±7.87%,#x0025;, that of the predominantly solid nodules (90% >solid > 75%) and mixed solid alongside cystic nodules (75% >solid > 50%) were 86.51±6.66% and 75.19±4.97%,#x0025;, respectively. Almost all the thyroid nodules were significantly decreased in size after MWA. After 12 months of MWA treatment, the average volume of the aforementioned thyroid nodules decreased from 8.69±8.79 to 1.84±3.11 ml, 10.94±9.07 to 2.58±3.34 ml, 9.92±6.27 to 0.25±0.42 ml, respectively. The mean symptom and cosmetic scores of the nodules showed significant (p < 0.000) improvement. The rates of the complications or side effects of MWA against the above-mentioned nodule types were 8.3% (3/36), 3.2% (1/31) and 0% (0/36), respectively.

CONCLUSIONS

The application of the IAR to quantify the success rate of thyroid nodule microwaves in the short term demonstrated that IAR was related to the internal components of the nodule. Although the IAR was not high when the thyroid component was mixed solid and cystic nodules (75% >solid > 50%), the final therapeutic effect was still satisfactory.

SFE-AFCE-SFMN 2022 consensus on the management of thyroid nodules: Thermal ablation

The SFE-AFCE-SFMN 2022 consensus deals with the management of thyroid nodules, a condition that is a frequent reason for consultation in endocrinology. In more than 90% of cases, patients are euthyroid, with benign non-progressive nodules that do not warrant specific treatment. The clinician's objective is to detect malignant thyroid nodules at risk of recurrence and death, toxic nodules responsible for hyperthyroidism or compressive nodules warranting treatment. The diagnosis and treatment of thyroid nodules requires close collaboration between endocrinologists, nuclear medicine physicians and surgeons, but also involves other specialists. Therefore, this consensus statement was established jointly by 3 societies: the French Society of Endocrinology (SFE), French Association of Endocrine Surgery (AFCE) and French Society of Nuclear Medicine (SFMN); the various working groups included experts from other specialties (pathologists, radiologists, pediatricians, biologists, etc.). This section deals with thermal ablation, which may constitute an alternative to thyroid surgery in selected patients.

Morphological, clinical, and functional efficacy in the short and medium-term after radiofrequency treatment of predominantly solid, large, and clinically relevant thyroid nodules in patients who are not candidates for surgery: The experience after 100 procedures

INTRODUCTION

Thyroid nodules (TN) are a prevalent pathology that can generate morbidity, in which case the traditional treatment is usually surgery.

OBJECTIVE

To analyse the efficacy of radiofrequency ablation (RFA) treatment as a therapeutic alternative in the combined clinical, morphological, and functional control of predominantly solid, benign and clinically relevant TNs in patients not subsidiary to surgery.

MATERIALS AND METHODS

A descriptive, retrospective, case series study was carried out to assess the efficacy and safety of the use of RFA. According to medical criteria, the selected patients underwent a clinical, ultrasound, and biochemical assessment prior to the procedure and then after the procedure at 1, 3, 6, and 12 months and then every 6-12 months according to medical criteria.

RESULTS

A total of 100 RFA were performed on 83 patients with 85 TNs of ≥2.5 cm with an initial volume (IV) of 21.48 ± 15.89 ml. After a mean of 1.17 RFA sessions per TN, the volume decreased progressively and significantly (p < 0.01 for all times compared to the initial value), with a mean volume reduction rate (VRR) in relation to the IV of 54.43 ± 19.56% at 1-month follow-up; 67.69 ± 17% at 3 months; 70.38 ± 15.46% at 6 months; 70.67 ± 17.27% at 12 months and 70.24 ± 17.7% at the last follow-up. 88% of the patients followed up >6 months achieved the combined objective of a volume reduction rate of more than 50% of the VI, thyroid normal function and absence of clinic; and in all of these, it was maintained until the final follow-up date. Acute complications (mostly mild and all transient) were reported in 9 of the 100 RFA performed.

CONCLUSION

Our findings validate in our setting the efficacy and safety of RFA in predominantly large and solid TNs, and add undescribed information to position the technique more favourably as a therapeutic alternative.

Meta-analysis of the efficacy and safety of thermal ablation for treating large benign thyroid nodules

OBJECTIVE

Many large benign thyroid nodules have symptoms and cosmetic problems. This study consisted of a meta-analysis to accurately assess the effect of thermal ablation on these nodules.

METHODS

The PubMed, Embase, Web of Science, and Scopus databases were systematically searched for retrospective or prospective studies of thermal ablation since June 1, 2021. The weighted mean differences of the measures were analysed before and after treatment.

RESULTS

A total of 10 eligible studies were included. By comparing the initial nodule volume with the nodular volume after thermal ablation, we found that the volume reduction rate was increased significantly after 1 month (SMD = 0.453, 95% CI: 0.323-0.583, p &lt; .001), 3 months (SMD = 0.655, 95% CI: 0.563-0.747, p &lt; .001), 6 months (SMD = 0.691, 95% CI: 0.607-0.774, p &lt; .001), and 12 months (SMD = 0.694, 95% CI: 0.583-0.803), p &lt; .001). The nodular volume was also found to decrease significantly, after 1 month (SMD = 2.381, 95% CI: 1.278-3.485, p &lt; .001), 3 months (SMD = 5.071, 95% CI: 2.386-7.756, p &lt; .001), 6 months (SMD = 5.363, 95% CI: 2.765-7.962, p &lt; .001), and 12 months (SMD = 8.194, 95% CI: 2.113-14.274), p &lt; .001). Symptom score (SMD = 4.419, 95% CI: 2.573-6.265, p &lt; .001)and cosmetic score (SMD = 4.245, 95% CI: 2.566-5.359, p &lt; .001) were reduced after thermal ablation.

CONCLUSIONS

Thermal ablation could become an alternative to manage large benign thyroid nodules.

[Does preoperative risk grading have clinical value for benign thyroid nodular ablation?]

OBJECTIVE

To explore the risk grading method for benign thyroid nodules before microwave ablation and the clinical significance of risk grading.

METHODS

This study was conducted among 527 patients undergoing ultrasound-guided microwave ablation of benign thyroid nodules between July, 2017 and December, 2020.Based on anatomic relationship of the thyroid nodules with the adjacent tissues, the ablation risk was classified into 4 levels: low, medium, high and extremely high risks.The incidence of severe complications and the rate of residual nodules following the ablation were recorded.

RESULTS

In the patients graded to have low, medium, high and extremely high preoperative risks, the incidences of severe complications following the ablation were 0%, 0.88%, 2.41% and 6.78%, respectively, showing no significant differences among the different risk groups (P > 0.05).The rates of postoperative residual nodules in the 4 risk groups were 1.59%, 6.14%, 14.43% and 71.19%, respectively, showing a significant difference between the low and medium risk groups and the high and extremely high risk groups (P < 0.001).

CONCLUSION

Preoperative risk grading for thyroid nodular ablation can be helpful for prevention of severe complications during ablation and prediction of residual nodules after ablation.

Residual, regrowth, and new growth of radiofrequency ablation for benign thyroid nodules of different volumes: two-year follow-up results

INTRODUCTION

Radiofrequency ablation (RFA) is recognized as an effective technique for the treatment of benign thyroid nodules (BTNs), although the long-term results are limited. This study aimed to evaluate the residual vital volume increase, regrowth, and new growth over a 2-year period after RFA among different nodule volume groups.

SUBJECTS AND METHODS

This retrospective study evaluated 135 patients with 153 BTNs who underwent ultrasound guided RFA. The BTNs were categorized into small (<10 mL), medium (10-30 mL), and large (>30 mL) according to the initial volume of BTNs prior to ablation. The volume changes of each nodule were analyzed at 1, 3, 6, 12 and 24 months after RFA. New growth was defined as the growth in volume not found in the early follow-up on ultrasonography.

RESULTS

The initial ablation ratio of all BTNs was 99.67%. The mean volume reduction ratio (VRR) of BTNs was 85.53% after 2-year follow-up. The small nodule group showed a lower VRR compared to the other two groups at the 1-month follow-up, and there was no difference of VRR at the subsequent follow-ups. The incidence of residual vital volume increase was 4.58%. The overall incidence of regrowth was 3.92% and the mean timing of regrowth was 16.71 months. New growth occurred in 18.95% of patients. No further treatment was required in the majority of cases.

CONCLUSION

RFA achieved a clinically relevant volume reduction in different sizes of single BTNs which persisted for at least 2 years, thereby preventing the need for retreatment.

Present Status of Thyroid Ablation in Europe: An International Survey among the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) Members

AIM

To evaluate the effective spread of image-guided thermal ablation in thyroid gland and to characterize its current perceptions among European interventional radiologists.

MATERIALS AND METHODS

A questionnaire with 29 multiple choice questions about thyroid ablation was sent as an E-blast to 4752 CIRSE members. Only those who completed the survey in all its parts were included in the study.

RESULTS

242/4752 (5.09%) participants (212 males and 30 females) completed and submitted the survey. A total of 160 subjects (66.1%) were familiar with any image-guided thermal ablations, but only 63 (26% of total population) usually perform thermal ablation for thyroid gland. Only 19.5% of the interviewed sample treats micropapillary thyroid tumours and the vast majority routinely uses radiofrequency ablation (84.4%).

CONCLUSION

There is a significant mismatch between thyroid ablation as reported by the literature and the relatively low percentage of interventional radiology actively performing such procedure in Europe. A considerable effort is required by the Cardiovascular and Interventional Radiological Society of Europe to fill this lack.

Long-term follow-up of the radiofrequency ablation of benign thyroid nodules: the value of additional treatment

PURPOSE

This study aimed to evaluate the efficacy of additional radiofrequency ablation (RFA) treatment for benign thyroid nodules.

METHODS

Electronic medical records at a single institution from September 2008 to August 2016 were searched, and consecutive patients treated with RFA due to benign thyroid nodules with cosmetic or symptomatic problems were enrolled. All patients were followed up for at least 30 months. The nodules were divided into three groups: group 1 included nodules that met the criteria for additional treatment and underwent additional treatment, group 2 included nodules that met the criteria but did not undergo additional treatment, and group 3 included nodules that did not meet the criteria. The ablation results were compared among the three groups in terms of the initial ablation ratio (IAR) and volume reduction ratio (VRR).

RESULTS

Ninety nodules from 88 patients were included in the study. At the last follow-up, group 1 showed a significantly smaller nodule volume and larger VRR (2.5 mL and 84.6%, respectively) than group 2 (8.1 mL and 39.8%, respectively, P<0.001), but did not present a significant difference from group 3 (0.9 mL, P=0.347, and 92.8%, P=0.238). The IAR was significantly higher in group 3 (94.5%) than in the other two groups (group 1, 81.1%; group 2, 82.8%; P<0.001).

CONCLUSION

Multiple treatment sessions achieve greater VRR. Therefore, additional treatment could be considered for patients who meet the corresponding criteria.

Effectiveness of High-intensity Focused Ultrasound (HIFU) Therapy of Solid and Complex Benign Thyroid Nodules - A Long-term Follow up Two-center Study

PURPOSE

To investigate the effectiveness of high-intensity focused ultrasound (HIFU) of solid and complex benign thyroid nodules.

METHODS

Fifty-eight patients with benign thyroid nodules were treated with HIFU at two centers from 2014-2019. The device, EchoPulse (Teraclion, Malakoff, France), heats the nodes to 80-90 °C. Nodal volumes were measured by ultrasound at regular intervals before and up to 12 months after therapy. In a retrospective long-term two-center study, average volume reductions in relation to baseline volume were statistically analyzed by the Wilcoxon signed-rank test. Side effects were documented.

RESULTS

In solid nodules, the average percent volume reductions at the 3, 6, 9, and 12-months follow-up were 49.98%, 46.40%, 65.77%, and 63.88%, respectively. The results were significant with p<0.05 in the Wilcoxon signed-rank test at the 3, 6, and 9-months follow-up. In complex nodules, the average percent volume reduction was 35.2% at 3 months, 36.89% at 6 months, and 63.64% at twelve months follow up. The results were significant with p<0.05 in the Wilcoxon signed-rank test at the 3- and 6-months follow-up. The complication rate was 5.2%. All complications occurred in patients with solid nodules.

CONCLUSION

The study showed that HIFU is an effective treatment method for both solid and complex nodules. The complication rate is relatively high at 5.2%. No long-term complications occurred. The solid nodules responded better to HIFU than complex nodules.

Minimally Invasive Techniques for the Management of Thyroid Nodules

Image-guided interventional techniques have emerged as promising treatments for thyroid disease. Percutaneous ethanol ablation, radiofrequency ablation, laser ablation, high intensity focused ultrasound, and microwave ablation have shown efficacy in treating benign thyroid disease. There is increasing evidence that these techniques may effectively treat papillary thyroid microcarcinomas, recurrent and metastatic disease, follicular neoplasms, and parathyroid lesions. They are performed in an outpatient setting, well-tolerated, with negligible risk for thyroid hormone supplementation, making them a popular alternative to surgical resection. In this comprehensive review, we discuss the devices, techniques, advantages, and disadvantages of each intervention, and summarize the published outcomes.

Nonsurgical Management of Thyroid Nodules: The Role of Ablative Therapies

CONTEXT

After a thorough evaluation most thyroid nodules are deemed of no clinical consequence and can be observed. However, when they are compressive, toxic, or involved by papillary thyroid carcinoma surgery or radioactive iodine (RAI) (if toxic) are the treatments of choice. Both interventions can lead to hypothyroidism and other adverse outcomes (eg, scar, dysphonia, logistical limitation with RAI). Active surveillance might be used for papillary thyroid microcarcinoma (PTMC) initially, but anxiety leads many cases to surgery later. Several ablative therapies have thus evolved over the last few years aimed at treating these nodules while avoiding described risks.

CASES

We present 4 cases of thyroid lesions causing concern (compressive symptoms, thyrotoxicosis, anxiety with active surveillance of PTMC). The common denominator is patients' attempt to preserve thyroid function, bringing into focus percutaneous ethanol injection (PEI) and thermal ablation techniques (radiofrequency ablation [RFA] being the most common). We discuss the evidence supporting these approaches and compare them with standard therapy, where evidence exists. We discuss additional considerations for the utilization of these therapies, their side-effects, and conclude with a simplified description of how these procedures are performed.

CONCLUSION

Thermal ablation, particularly RFA, is becoming an attractive option for managing a subgroup of solid thyroid nodules, while PEI has a role in managing thyroid cysts and a select group of PTMC. Their role in the algorithm of thyroid nodule management is still being refined and technical expertise will be essential to reproduce the reported results into everyday practice.

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.

Minimally-invasive treatments for benign thyroid nodules: recommendations for information to patients and referring physicians by the Italian Minimally-Invasive Treatments of the Thyroid group

PURPOSE

In this paper, the members of the Italian Working Group on Minimally-Invasive Treatments of the Thyroid (MITT group) aim to summarize the most relevant information that could be of help to referring physicians and that should be provided to patients when considering the use of MITT for the treatment of benign thyroid nodules.

METHODS

An interdisciplinary board of physicians with specific expertise in the management of thyroid nodules was appointed by the Italian MITT Group. A systematic literature search was performed, and an evidence-based approach was used, including also the knowledge and the practical experience of the panelists to develop the paper.

RESULTS

The paper provides a list of questions that are frequently asked by patients to operators performing MITT, each with a brief and detailed answer and more relevant literature references to be consulted.

CONCLUSIONS

This paper summarizes the most relevant information to be provided to patients and general practitioners/referring physicians about the use of MITT for the treatment of benign thyroid nodules.