Effect of ultrasound-guided interstitial laser photocoagulation on benign solitary solid cold thyroid nodules - a randomised study

Efficacy of echolaser smart interface-guided laser ablation in volume reduction of symptomatic benign thyroid nodules

Background

The management of benign symptomatic thyroid nodules until recent years has been limited to surgery, radioactive iodine treatment, or surveillance which is associated with the burden of morbidity of complications or symptom non-relief as well as cost. Laser ablation has emerged as a minimally invasive alternative, this uses laser energy to thermally ablate nodule tissue, leading to volume reduction and symptom relief. Long-term treatment response data is growing but remains limited in the United States. Our study aims to quantify the effectiveness of laser ablation in reducing the volume of thyroid nodules over a 12 to 18-month period.

Materials and methods

Retrospective review of data was conducted for 63 adults with cytologically benign, solid symptomatic thyroid nodules ranging from 1.333 cm3 to 103.794 cm3 in volume. Ultrasound-guided laser thermal ablation was performed on all nodules using EchoLaser X4 Smart Interface device with 1064 nm diode laser to deliver total ablation energy (joules), calculated per device guidelines. Serial sonographic volume measurements were conducted 1 month, 3 -6 months, 6 - 12 months, and 12 to 18 months post-ablation intervals.

Results

Study cohort was comprised of 63 thyroid nodules. reduction in nodule volume increased progressively over time, with median reductions of 46.05% [STD 21.8] at 1 month, 60.33% [STD 20.1] at 3-6 months, 68.69% [STD 18.8] at 6-12 months, and 64.04% [STD 19.27] at 12-18 months. A total of 62, 56, 42, and 17 nodules had available data for analysis at these respective intervals.

Conclusion

This study demonstrated a marked progressive reduction of thyroid nodule volume following ablation. The treatment appears to be consistently effective in reducing symptoms across a wide range of nodule sizes, although the degree of volume reduction varies. The results of our study underscore the potential of laser ablation as a viable treatment option for thyroid nodules, with a sustained reduction in nodule volume observed over an extended post-procedure period.

US-guided percutaneous ablation of thyroid nodules with 177LU-MAA (LUTMA) - Feasibility study

PURPOSE

The main purpose is to evaluate the safety, and efficacy of 177Lutetium labeled macroaggregated albumin (LUTMA) ablation of thyroid nodules.

MATERIALS AND METHODS

Patients with confirmed benign nodules who were not candidate or did not accept surgery were enrolled. Under ultrasonography (USG) guidance, LUTMA which was produced in our department, was administered into the nodules. Nodule volumes were assessed via USG before the injection and at 1-week, 1-month, and 3-months post-treatment. We calculated the volume reduction rates (VRRs) for these intervals. To detect extranodular activity leakage, patients underwent SPECT/CT imaging at one hour, 24 h, and one week post-injection.

RESULTS

Fifteen patients (male: 12, female: 3) with benign thyroid nodules were eligible to join this study. These nodules were categorized as cystic (n = 9), solid (n = 3), or mixed (n = 3). Median nodules volume was 6.59 ml (range: 0.56-55 ml). Predicted absorbed dosee to the nodules varied between 10-1036 Gy. The VRRs at 3 months was 85% for all nodule types with gradual increases over time: 0%-92%, 20%-97%, and 28%-98% at 1 week, 1 month, and 3-months, respectively. The median VRR of cystic nodules was 89% (range: 81%-98%) at 3-months. It is significantly higher than solid ones (P = .009). None of the patients experienced adverse reactions or discomfort during the injection or follow-up.

CONCLUSION

LUTMA treatment significantly reduces the volume of benign thyroid nodules, offering relief from disease-associated symptoms and cosmetic concerns. It emerges as a promising alternative to surgical and other local treatments for benign thyroid nodule ablation.

CLINICAL SIGNIFICATION

LUTMA is a novel theranostic radiopharmaceutical which is promising in local ablative treatment of benign thyroid nodules.

Brazilian Consensus on the Application of Thermal Ablation for Treatment of Thyroid Nodules: A Task Force Statement by the Brazilian Society of Interventional Radiology and Endovascular Surgery (SOBRICE), Brazilian Society of Head and Neck Surgery (SBCCP), and Brazilian Society of Endocrinology and Metabolism (SBEM)

There is increasing interest in ultrasound-guided ablation treatments for thyroid diseases, including benign and malignant ones. Surgeons, radiologists, and endocrinologists carry out these treatments, and various organizations within these specialties have recently released multiple international consensus statements and clinical practice standards. The aim of the present consensus statement is to provide guidance, cohesion, and standardization of best practices for thermal ablation procedures of thyroid nodules. The statement includes the indications for these procedures, preprocedural evaluations, technical aspects of the procedures, posttreatment care, follow-up, complications, and training recommendations. This document was written by a panel of specialists from the Brazilian Society of Interventional Radiology and Endovascular Surgery (SOBRICE), the Brazilian Society of Head and Neck Surgery (SBCCP), and the Brazilian Society of Endocrinology and Metabolism (SBEM). The statement does not aim to provide criteria for assessing the capability of specialists to perform the procedure. Instead, it aims to promote the standardization of best practices to reduce potential adverse outcomes. Additionally, it strives to enhance the delivery of high-quality care and the widespread adoption of these technologies on a national level. The recommendations collectively serve as a guidebook for applying best practices in thyroid ablation.

Assessing the relative effectiveness of various ultrasound-guided ablation techniques for treating benign thyroid nodules: A systematic review and network meta-analysis

BACKGROUND

Benign thyroid nodules (BTNs) represent a prevalent clinical challenge globally, with various ultrasound-guided ablation techniques developed for their management. Despite the availability of these methods, a comprehensive evaluation to identify the most effective technique remains absent. This study endeavors to bridge this knowledge gap through a network meta-analysis (NMA), aiming to enhance the understanding of the comparative effectiveness of different ultrasound-guided ablation methods in treating BTNs.

METHODS

We comprehensively searched PubMed, Embase, Cochrane, Web of Science, Ovid, SCOPUS, and ProQuest for studies involving 16 ablation methods, control groups, and head-to-head trials. NMA was utilized to evaluate methods based on the percentage change in nodule volume, symptom score, and cosmetic score. This study is registered in INPLASY (registration number 202260061).

RESULTS

Among 35 eligible studies involving 5655 patients, NMA indicated that RFA2 (radiofrequency ablation, 2 sessions) exhibited the best outcomes at 6 months for percentage change in BTN volume (SUCRA value 74.6), closely followed by RFA (SUCRA value 73.7). At 12 months, RFA was identified as the most effective (SUCRA value 81.3). Subgroup analysis showed RFA2 as the most effective for solid nodule volume reduction at 6 months (SUCRA value 75.6), and polidocanol ablation for cystic nodules (SUCRA value 66.5).

CONCLUSION

Various ablation methods are effective in treating BTNs, with RFA showing notable advantages. RFA with 2 sessions is particularly optimal for solid BTNs, while polidocanol ablation stands out for cystic nodules.

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.

Radiofrequency ablation and related ultrasound-guided ablation technologies for treatment of benign and malignant thyroid disease: An international multidisciplinary consensus statement of the American Head and Neck Society Endocrine Surgery Section with the Asia Pacific Society of Thyroid Surgery, Associazione Medici Endocrinologi, British Association of Endocrine and Thyroid Surgeons, European Thyroid Association, Italian Society of Endocrine Surgery Units, Korean Society of Thyroid Radiology, Latin American Thyroid Society, and Thyroid Nodules Therapies Association

BACKGROUND

The use of ultrasound-guided ablation procedures to treat both benign and malignant thyroid conditions is gaining increasing interest. This document has been developed as an international interdisciplinary evidence-based statement with a primary focus on radiofrequency ablation and is intended to serve as a manual for best practice application of ablation technologies.

METHODS

A comprehensive literature review was conducted to guide statement development and generation of best practice recommendations. Modified Delphi method was applied to assess whether statements met consensus among the entire author panel.

RESULTS

A review of the current state of ultrasound-guided ablation procedures for the treatment of benign and malignant thyroid conditions is presented. Eighteen best practice recommendations in topic areas of preprocedural evaluation, technique, postprocedural management, efficacy, potential complications, and implementation are provided.

CONCLUSIONS

As ultrasound-guided ablation procedures are increasingly utilized in benign and malignant thyroid disease, evidence-based and thoughtful application of best practices is warranted.

Long-Term Efficacy of Ultrasound-Guided Laser Ablation for Papillary Thyroid Microcarcinoma: Results of a 10-Year Retrospective Study

Background: The aim of this study was to evaluate the 10-year efficacy and safety of laser ablation (LA) for the treatment of solitary papillary thyroid microcarcinoma (PTMC). Methods: LA was performed on patients with low-risk PTMC (diagnosed using fine-needle aspiration cytology) who refused or were ineligible for surgery between 2008 and 2011. Ultrasonography was performed to evaluate the ablated volumes and potential recurrences on the day after the procedure, as well as at 1 week, 1, 3, and 6 months, and every 6 months thereafter for 10 years. Computed tomography (CT) with contrast enhancement and positron emission tomography/CT was performed to evaluate local recurrences and distant metastases. Results: A total of 90 PTMCs in 90 patients were treated in a single session of LA, and the procedure was well tolerated by the patients. The mean follow-up duration was 112 months. By 3-10 months after the LA, all the ablation areas had disappeared or presented as scars. The disappearance rate was 100% after 12 months. Thyroid hormone and autoantibody levels did not change significantly after the treatment. Three patients experienced transient voice changes, but each recovered within 1 month. Additional PTMC foci were subsequently detected in previously untreated areas in five patients (5.5%) 17-56 months after the treatment. A metastatic lymph node was detected in one patient (1.1%) within two months of the treatment; however, it was determined to be an undetected cancer metastasis, rather than a recurrence. All the patients with recurrence underwent surgery, and there were no instances of recurrence after >5 years. Conclusions: LA is effective and safe for the treatment of low-risk PTMCs. A thorough examination of multifocality and lymph node metastasis status is required before considering LA treatment.

A study on the efficacy of microwave ablation for benign thyroid nodules and related influencing factors

OBJECTIVES

To explore the efficacy of microwave ablation (MWA) in the treatment of benign thyroid nodules, and analyze related influencing factors.

METHODS

The clinical and ultrasound data of 115 patients with 115 benign thyroid nodules treated with MWA were retrospectively analyzed. The volume of nodules at 1, 3, 6, and 12 months after the procedure was obtained, and the volume reduction rate (VRR) at each time point was calculated. With VRR > 90% as the criterion for nodule cure, binary logistic regression was employed to screen the factors that affect the efficacy.

RESULTS

① At 1, 3, 6, and 12 months after the procedure, the volume of nodules continued to decrease, the VRR gradually increased, and the differences at each time point were statistically significant (p < 0.05). A total of 29 (25.21%) nodules disappeared completely at 12 months after the procedure; ② Multivariate stepwise logistic regression showed that there was a statistically significant difference for the internal component of nodules, enhancement mode, and immediate volume after the procedure in determining the ablation efficacy (p < 0.05); ③ The ROC curve was plotted for predicting the efficacy of MWA, with the results showing that the AUC, sensitivity, specificity, and accuracy were 0.82, 67.50, 88.00, 79.10%, respectively; ④ 11 cases (9.56%) had side effects, 10 cases (8.70%) had minor complications, and three cases (2.61%) had major complications.

CONCLUSION

MWA is safe and effective in the treatment of benign thyroid nodules. The internal component of nodules, enhancement mode, and immediate volume after the procedure are independent factors that affect the efficacy of ablation.

Predictor Analysis in Radiofrequency Ablation of Benign Thyroid Nodules: A Single Center Experience

Purpose

To confirm the efficacy of ultrasound (US) guided radiofrequency ablation (RFA) in the treatment of benign thyroid nodules, we evaluated as primary outcome the technical efficacy and clinical success in a single center dataset. The secondary outcome was to find a correlation between nodules' pre-treatment features and volume reduction rate (VRR) ≥75% at 12 months after RFA and during follow-up period.

Methods

This retrospective study included 119 consecutive patients (99 females, 20 males, 51.5 ± 14.4 years) with benign thyroid nodules treated in our hospital between October 2014 and December 2018 with a mean follow-up of 26.8 months (range 3-48). Clinical and US features before and after RFA were evaluated by a US examination at 1, 3, 6, 12 months and annually thereafter up to 48 months.

Results

The median pre-treatment volume was 22.4 ml; after RFA we observed a statistically significant volume reduction from the first month (11.7 ml) to the last follow-up (p < 0.001 for all follow-up times). The median VRR was 47.1, 55.3, 61.2, 67.6, 72.8, 71.3, and 62.9% at 1, 3, 6, 12, 24, 36, and 48 months of follow-up respectively, showing a progressive significant improvement up to 24 months (VRRs 1 vs 3 months, 3 vs 6 months and 6 vs 12 months p < 0.001, 12 vs 24 months p = 0.05) while no differences at 24 vs 36 and 36 vs 48 months were observed. Symptoms improved significantly (complete resolution 64.35%, partial resolution 35.65%), and neck circumference was reduced as compared to pre-treatment (p < 0.001). Lower pre-treatment neck circumference (37.5 vs 36.0 cm, p = 0.01) was a positive predictor of VRR ≥75% at 12 months. Macrocystic echostructure (HR 2.48, p 0.046) and pre-treatment volume >22.4 ml (HR 0.54, p 0.036) were found to be independent positive and negative predictors of VRR ≥75% respectively. One-month post RFA VRR ≥50% represented the best positive predictor of technical success.

Conclusions

This study confirmed the efficacy of RFA in the treatment of benign thyroid nodules. In particular we show that by selecting macrocystic nodules smaller than 22.4 ml better long-term response can be achieved, which is predicted by an early shrinkage of the nodule.

Comparative efficacy of different ultrasound-guided ablation for the treatment of benign thyroid nodules: Systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Percutaneous ablation is currently deemed an additionally treatment option for benign thyroid nodules in the world, but possibly different effect among the ablation modalities is not clear. So we aim to evaluate the efficacy and complications of thermal/chemical ablation by network meta-analysis.

MATERIALS AND METHODS

In the network meta-analysis, PubMed, EMBASE and the Cochrane Library databases were searched from 1980 to 2020. Studies of adults with thyroid benign nodules under percutaneous ablation therapy were included. Percentage mean volume change, symptom score change, cosmetic score change and complications were evaluated by network meta-analysis.

RESULTS

In the network meta-analysis, Radiofrequency Ablation(RFA) with 2 treatment sessions group was associated with the highest reduction for the mean volume change during 6-month follow-up (MD = 79.09 and 95% CrI:48.23-89.94). There is no significant difference in the incidence of complications. Subgroup analysis showed that 2 sessions of Radiofrequency Ablation (RFA) ranks the highest probability (surface under the cumulative ranking curve (SUCRA) values 77.9) of being the most efficacious treatment for solid or predominantly solid benign nodules. Ethanol ablation (EA) ranked first (SUCRA value 81.1) in the treatment for cyst or predominantly cyst benign nodules.

CONCLUSION

RFA appears to be superior to other US-guided percutaneous ablation in reducing benign thyroid nodule volume during short- and long-term follow-up. In the subgroup analysis, RFA with 2 treatment sessions showed the most significant effectiveness for solid benign thyroid nodules and EA showed more effectiveness to decrease the volume of cyst benign thyroid nodules.

2020 European Thyroid Association Clinical Practice Guideline for the Use of Image-Guided Ablation in Benign Thyroid Nodules

Standard therapeutic approaches for benign thyroid lesions that warrant intervention are surgery for cold and either surgery or radioiodine for autonomously functioning thyroid nodules (AFTN). Image-guided thermal ablation (TA) procedures are increasingly proposed as therapy options for selected clinical conditions. Due to mounting scientific evidence and widening availability, ETA considered it appropriate to develop guidelines for the use of TA in adult patients. TA procedures are well tolerated, but a dedicated training of the operators is required and information on possible complications needs to be shared with the patients. The following factors should be considered when weighing between observation, surgery, and TA for benign thyroid nodules. In solid non-hyperfunctioning nodules, TA induces a decrease in thyroid nodule volume, paralleled by improvement in symptoms. Nodule re-growth is possible over time and may necessitate repeat treatment, or surgery, in a dialogue with the patient. In AFTN, radioactive iodine is the first-line treatment, but TA may be considered in young patients with small AFTN due to higher probability of restoring normal thyroid function and avoidance of irradiation. In cystic nodules, ethanol ablation (EA) is the most effective and least expensive treatment. TA may be considered for cystic lesions that relapse after EA or have a significant residual solid component following drainage and EA. TA should be restricted to benign lesions that cause symptoms or cosmetic concern. Presently, laser and radiofrequency ablation are the most thoroughly assessed techniques, with similar satisfactory clinical results. Microwaves and high-intensity focused ultrasound therapy options remain to be fully evaluated.

European Thyroid Association Survey on Use of Minimally Invasive Techniques for Thyroid Nodules

OBJECTIVE

Image-guided interventional ultrasound (US) techniques represent diagnostic and therapeutic tools for non-surgical management of thyroid nodular disease. We sought to investigate the attitude of European Thyroid Association (ETA) members towards the use of minimally invasive techniques (MIT) in diagnosis/therapy of symptomatic nodular goitre.

METHODS

ETA members were invited to participate in an online survey investigating the use of MIT in benign and malignant thyroid nodular disease. Of 865 invited members, 221 (25.5%) completed the survey. The respondents were from 40 countries; 139 (74.7%) were from European countries.

RESULTS

Respondents personally performed thyroid US (91.6%), Fine needle aspiration (FNA; 75.3%), ethanol ablation (EA; 22.1%), core needle biopsy (CNB; 11%) and thermal treatments (4.8%). When skills and/or technology were unavailable, only 13.4% referred patients "often" or "always" to other centres with specific expertise in this field. Surgery was the preferred first option in patients with recurrent cysts, 4.0 cm benign nodules, local (radioiodine-avid or non-avid) lymph node metastases, or papillary cancers <1.0 cm. For autonomously functioning nodules radioactive iodine treatment was the preferred choice, followed by surgery. Thermal ablation (TA) was the preferred option only for a 4 cm benign nodule in old patients with comorbidities.

CONCLUSIONS

US, US-guided FNA and surgery were available to nearly all respondents, while MIT was not. CNB and EA were employed only by about 1/3 of the respondents and TA procedures were available and personally performed only by a minority. For most thyroid lesions, surgery was the preferred option versus thermal therapies. The ETA needs to develop guidelines and establish teaching to overcome geographic inequality and promote the use of MIT as a valid therapy option in appropriate cases.

Efficacy of thermal ablation in benign non-functioning solid thyroid nodule: A systematic review and meta-analysis

BACKGROUND

Image-guided thermal ablations are commonly used in the treatment of thyroid nodules. Radiofrequency ablation (RFA) and laser ablation are the most commonly used. Here we aimed to obtain solid evidence of the long-term efficacy of RFA and laser ablation in benign non-functioning solid thyroid nodules (BNFSTN).

METHODS

PubMed, CENTRAL, Scopus, and Web of Science were searched until March 2019. Studies reporting the effectiveness of RFA or laser ablation in patients with BNFSTN in terms of volume reduction rate (VRR), compressive symptoms and cosmetic concerns were included. Complications were also assessed.

RESULTS

Out of 963 papers, 12 studies on RFA and 12 on laser ablation were included, assessing 1186 and 2009 BNFSTNs, respectively. Overall, VRR at 6, 12, 24, and 36 months was 60%, 66%, 62%, and 53%. VRR of RFA was 68%, 75%, and 87%, respectively. VRR of laser ablation was 48%, 52%, 45%, and 44%, respectively. Baseline volume of nodules undergone RFA was significantly smaller compared to laser ablation (20.1 ± 22.4 versus 24.6 ± 23.6 ml; p < 0.01). Nodules smaller than 30 ml obtained better outcomes than larger ones. A significant reduction in compressive symptoms and cosmetic concerns was found after RFA.

CONCLUSIONS

This meta-analysis showed that both RFA and laser ablation are able to obtain a significant volume reduction in BNFSTNs. A significant volume reduction is already evident at 6 months after thermal ablation and results are stable over the time.

Single-Fiber Laser Ablation in Treating Selected Metastatic Lymph Nodes of Papillary Thyroid Carcinoma and Benign Cold Thyroid Nodules-Preliminary Results

Background and Objectives

To evaluate the feasibility and efficacy of single‐fiber laser ablation (LA) under ultrasound guidance and appropriate ablation modes in the treatment of selected metastatic lymph nodes of papillary thyroid carcinoma (PTC) and benign cold thyroid nodules

Study Design/Materials and Methods

A total of 18 patients (consisting of 8 patients with 18 metastatic lymph nodes of PTC and 10 patients with 10 benign cold thyroid nodules) each underwent one session of single‐fiber LA under ultrasound guidance. On the basis of the sizes of the nodules, the ablation modes were chosen accordingly. The single‐dot ablation mode was used in the nodules with three orthogonal diameters measuring no greater than 10 mm in diameter, with a dot, a level and an insertion. The double‐dots overlapping ablation mode was used in the nodules with the largest diameters measuring greater than 10 mm (in which the nodules measured no more than 15 mm in diameter and with the other two perpendicular diameters measuring no greater than 10 mm in diameter) with two dots, a level and two insertions. The multiple levels and dots overlapping ablation mode was used in the nodules with the three orthogonal diameters all measuring larger than 10 mm, with multiple dots, levels and insertions.

Results

After 12 months of follow‐up in the treated nodules of the metastatic lymph nodes of PTC and benign cold thyroid nodules, the mean baseline volumes decreased from 0.29 ± 0.12  to 0.03 ± 0.03 ml and 3.85 ± 0.64 to 1.1 ± 0.37 ml, respectively, and the mean volume reduction ratios (VRRs), which was calculated as {[(initial volume−final volume) × 100%]/initial volume}, were 90.3 ± 7.6% and 72 ± 5.8%, respectively. There were six ablative zones that completely disappeared, whereas the ablative zones that still existed presented as scar‐like areas or small hyperechoic areas that were compatible with scar tissue among the 18 malignant nodules at the last follow‐up.

Conclusions

Single‐fiber LA under ultrasound guidance, with the appropriate ablation modes, is feasible and effective for the treatment of selected metastatic lymph nodes of PTC and benign cold thyroid nodules. This study suggests that single‐fiber LA may be applied to selected cases with appropriate ablation modes. Lasers Surg. Med. 2019 © 2019 Wiley Periodicals, Inc.

Long-term outcome following laser therapy of benign cystic-solid thyroid nodules

OBJECTIVE

Laser therapy (LT) is considered a safe and effective procedure for inducing thyroid nodule necrosis, fibrosis and shrinkage. Little is known about long-term efficacy of LT in benign complex thyroid nodules, which we report here.

DESIGN AND METHODS

One hundred and ten euthyroid outpatients (28 men and 82 women; median age 48 years (range 17-82)) with a recurrent cytologically benign cystic (≥2 mL cyst volume) thyroid nodule causing local discomfort were assigned to LT. LT was performed after complete cyst aspiration and under continuous ultrasound (US) guidance. Nineteen patients (17 within 6 months) had surgery after LT. The median follow-up for the remaining 91 patients was 45 months (range: 12-134).

RESULTS

The overall median nodule volume in the 110 patients decreased from 9.0 mL (range: 2.0-158.0) to 1.2 mL (range: 0.0-85.0) (P < 0.001) at the final evaluation, corresponding to a median reduction of 85% (range: -49 to 100%). Remission of the cystic part (volume ≤1 mL) was obtained in 82 of 110 (75%) patients after LT. The median cyst volume decreased from 6.3 mL (range: 2.0-158.0) to 0.0 mL (range: 0.0-85.0) (P < 000.1), corresponding to a median reduction of 100% (range: -49 to 100%). These results correlated with a significant decrease in pressure as well as cosmetic complaints. Side effects were restricted to mild local pain.

CONCLUSION

US-guided aspiration and subsequent LT of benign recurrent cystic thyroid nodules results in a satisfactory long-term clinical response in the majority of patients. LT constitutes a clinically relevant alternative to surgery in such patients.

Minimally-invasive treatments for benign thyroid nodules: a Delphi-based consensus statement from the Italian minimally-invasive treatments of the thyroid (MITT) group

Benign thyroid nodules are a common clinical occurrence and usually do not require treatment unless symptomatic. During the last years, ultrasound-guided minimally invasive treatments (MIT) gained an increasing role in the management of nodules causing local symptoms. In February 2018, the Italian MIT Thyroid Group was founded to create a permanent cooperation between Italian and international physicians dedicated to clinical research and assistance on MIT for thyroid nodules. The group drafted this list of statements based on literature review and consensus opinion of interdisciplinary experts to facilitate the diffusion and the appropriate use of MIT of thyroid nodules in clinical practice. (#1) Predominantly cystic/cystic symptomatic nodules should first undergo US-guided aspiration; ethanol injection should be performed if relapsing (level of evidence [LoE]: ethanol is superior to simple aspiration = 2); (#2) In symptomatic cystic nodules, thermal ablation is an option when symptoms persist after ethanol ablation (LoE = 4); (#3) Double cytological benignity confirmation is needed before thermal ablation (LoE = 2); (#4) Single cytological sample is adequate in ultrasound low risk (EU-TIRADS ≤3) and in autonomously functioning nodules (LoE = 2); (#5) Thermal ablation may be proposed as first-line treatment for solid, symptomatic, nonfunctioning, benign nodules (LoE = 2); (#6) Thermal ablation may be used for dominant lesions in nonfunctioning multinodular goiter in patients refusing/not eligible for surgery (LoE = 5); (#7) Clinical and ultrasound follow-up is appropriate after thermal ablation (LoE = 2); (#8) Nodule re-treatment can be considered when symptoms relapse or partially resolve (LoE = 2); (#9) In case of nodule regrowth, a new cytological assessment is suggested before second ablation (LoE = 5); (#10) Thermal ablation is an option for autonomously functioning nodules in patients refusing/not eligible for radioiodine or surgery (LoE = 2); (#11) Small autonomously functioning nodules can be treated with thermal ablation when thyroid tissue sparing is a priority and ≥80% nodule volume ablation is expected (LoE = 3).

Percutaneous laser ablation of benign thyroid nodules: a one year follow-up study

Objective

To evaluate safety and effectiveness of nodule volume reduction and thyroid function after percutaneous laser ablation treatment in patients with benign nonfunctioning thyroid nodules.

Methods

Prospective single-center study, from January 2011 to October 2012, which evaluated 30 euthyroid and thyroid antibodies negative patients with benign solitary or dominant nodule with indication of treatment due to compressive symptoms and aesthetic disturbances. The clinical and laboratory (thyroid ultrasound, TSH, FT4, TG, TG-Ab, TPO-Ab and TRAb levels) evaluations were performed before the procedure, and periodically 1 week, 3 months and 6 months after. The ablation technique was performed under local anesthesia and sedation. In each treatment, one to three 21G spinal needle were inserted into the thyroid nodule. The laser fiber was positioned through the needle, which was then withdrawn 10mm to leave the tip in direct contact with the nodule tissue. Patients were treated with a ND: Yag-laser output power of 4W and 1,500 to 2,000J per fiber per treatment. The entire procedure was performed under US guidance.

Results

Thirty patients, with a total of 31 nodules submitted to laser ablation were evaluated. The median volumetric reduction of the nodule was approximately 60% after 12 months. No statistical significance was observed on thyroid function and antibodies levels. There was a peak on the level of thyroglobulin after the procedure due to tissue destruction (p<0.0001). No adverse effects were observed.

Conclusion

Percutaneous laser ablation is a promising outpatient minimally invasive treatment of benign thyroid nodule.

Image-guided chemical and thermal ablations for thyroid disease: Review of efficacy and complications

Image-guided ablation of thyroid disease is increasingly being commonly reported. Techniques including ethanol injection and thermal ablation using radio-frequency, laser, and microwave devices have been described. Minimally invasive approaches to the management of benign cystic, solid, and functional thyroid nodules as well as both primary and recurrent thyroid malignancy have been reported. The purpose of this article is to review the current evidence relating to image-guided ablation of thyroid disease with a focus on clinical outcomes and complication rates for patients treated with this minimally invasive approach.

A single session of laser ablation for toxic thyroid nodules: three-year follow-up results

PURPOSE

To confirm the effectiveness of laser ablation on toxic nodules in a large population with three years of follow-up.

MATERIAL AND METHODS

Between 2009 and 2014, we treated 82 patients with hyperthyroidism related to the presence of a toxic nodular goitre. Patients were pre-treated pharmacologically with methimazole prior to single session of laser ablation (LA) and then followed up every 3 months with FT4 and TSH blood tests as well as ultrasound examination of the nodules treated.

RESULTS

All patients responded to the treatment. The median nodule volume decreased from 12 ml (range 5-118 ml) to 5 ml (range 1.2-40 ml) after three years (p < 0.001). The percentage of patients who discontinued methimazole therapy was reduced by increasing the initial volume of the toxic nodule. In nodules with a volume less than 5 ml, all patients were able to suspend methimazole; this percentage was reduced to 90.2% in nodules with a volume between 5 and 15 ml, 61.1% in those with volume 15-25 ml and only 28.5% in nodules larger than 25 ml. We had no major complications but only moderate pain and fever in the evening, a few hours after ablation therapy in 10% of treated patients.

CONCLUSIONS

Single session of LA of toxic thyroid nodules is effective and safe, especially in nodules with a volume under 15 ml.

Statement and Recommendations on Interventional Ultrasound as a Thyroid Diagnostic and Treatment Procedure

The recently published guidelines of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) on interventional ultrasound (INVUS)-guided procedures summarize the intended interdisciplinary and multiprofessional approach. Herewith, we report on recommendations for interventional procedures for diagnosis and treatment of the thyroid gland.

A comparison of laser with radiofrequency ablation for the treatment of benign thyroid nodules: a propensity score matching analysis

PURPOSE

To compare technique efficacy and safety of laser ablation (LA) and radiofrequency ablation (RFA) in treatment of benign thyroid nodules.

MATERIALS AND METHODS

Institutional review board approval was obtained, and patients' consent was waived. 601 nodules were treated from May 2009 to December 2014 at eight centres, 449 (309 females, age 57 ± 14 years) with LA and 152 (107 females, age 57 ± 14 years) with RFA. A matched cohort composed of 138 patients from each group was selected after adjustment with propensity score matching. Factors influencing volume reduction at 6 and 12 months and complications were evaluated.

RESULTS

No significant differences were observed in the baseline characteristics between groups after propensity score matching adjustment. Mean nodule reduction at 6 and 12 months was -67 ± 19% vs. -57 ± 21% (p < 0.001) - 70 ± 19% vs. -62 ± 22% (p = 0.001) in LA group and in RFA group, respectively. Nodules with volume >30 mL had significantly higher percentage volume reduction at 6 and 12 months (-69 ± 19 vs. -50 ± 21, p = 0.001) and (-73 ± 18 vs. -54 ± 23 8, p = 0.001) in the LA group than in the RFA group, respectively. In both groups, operator's skills affected the results. Major complications occurred in 4 cases in each group (p = 0.116) Conclusions: LA and RFA showed nearly similar outcome but LA was slightly more effective than RFA in large nodules. Operator's skills could be crucial in determining the extent of nodule volume reduction regardless of the used technique.

Percutaneous laser ablation for benign thyroid nodules: a meta-analysis

Purpose

To evaluate percutaneous laser ablation in treating benign thyroid nodules, we conducted a meta-analysis based on summarizing existing researches.

Materials and Methods

A literature search for clinical trial was performed in PubMed, Cochrane Library and Excerpt Medica Database. The qualities of included studies were evaluated. We calculated the indexes with mean difference. Heterogeneity and publication bias were tested and explored. We performed subgroup analyses and sensitivity analysis further.

Results

A total of 19 researches and 2137 patients were included in this meta-analysis. The pooled estimates of nodule volume were statistically significant after percutaneous laser ablation for 1 month, 3 month, 6month, 12month, 24month and 36month(P < 0.05). The pooled estimate of thyroid-stimulating hormone was statistically significant after percutaneous laser ablation for 1 and 12 month (P = 0.008 and P = 0.03). The pooled estimate of free triiodothyronine was no statistically significant after percutaneous laser ablation for all follow-up intervals. The pooled estimate of free tetraiodothyronin was statistically significant after percutaneous laser ablation1 month (P = 0.004). The pooled estimate of thyroglobulin was statistically significant after percutaneous laser ablation 24 month (P = 0.04). The heterogeneity was found and the source of heterogeneity was explored in nodule volume for 6 and 12 month. No publication bias was found.

Conclusions

This meta-analysis demonstrated that percutaneous laser ablation was safe and useful in shrinking benign thyroid nodules volume, improving thyroid function, relieving symptoms of pressure and esthetic, especial for hyper-vascular benign thyroid nodules. Larger number of high-quality prospective studies still needs to be performed.

Radiofrequency ablation vs. microwave ablation for patients with benign thyroid nodules: a propensity score matching study

PURPOSE

To compare the efficacy and the safety of radiofrequency ablation and microwave ablation for treatment of benign thyroid nodules using a propensity score matching study design.

METHODS

Two hundred and sixty patients with benign thyroid nodules were studied retrospectively, including 102 patients treated with radiofrequency ablation and 158 treated with microwave ablation. To reduce confounding bias due to retrospective assignment, propensity score matching was performed to balance the preablation data of the two groups. After matching, a total of 102 patient pairs (1:1) were created. The volume reduction ratio, therapeutic success rate, symptom and cosmetic score, and major complication were compared between the two groups at 1, 3, 6, and 12 months after treatment.

RESULTS

Between the well-matched groups, no significant differences were found in all nodule volume-related end points at 6 months (volume reduction ratio: 79.4 vs. 77.2 %, P = 0.108; symptom score: 2.1 vs. 1.9, P = 0.456; cosmetic score: 2.1 vs. 2.3, P = 0.119; therapeutic success rate: 99 vs. 97 %, P = 0.621) and 12 months (volume reduction ratio: 83.6 vs. 81.6 %, P = 0.144; symptom score: 1.5 vs. 1.5, P = 0.869; cosmetic score: 1.6 vs. 1.7, P = 0.409; therapeutic success rate: 100 vs. 100 %, P > 0.99) after treatment. No major complications occurred in either group (P > 0.99).

CONCLUSIONS

With well-matched groups and consistent procedure design, our results demonstrated that the volume reduction ratio, therapeutic success rate, symptom and cosmetic score, and complications related to treatment for the two techniques are equivalent. Radiofrequency ablation and microwave ablation are both effective and safe methods in treating benign thyroid nodules.

Factors related to recurrence of the benign non-functioning thyroid nodules after percutaneous microwave ablation

PURPOSE

To determine the factors affecting the recurrence of the solitary benign thyroid nodules (BTN) after microwave ablation (MWA).

MATERIALS AND METHODS

Between January 2013 and January 2015, a total of 110 patients with at least one solid thyroid nodule (solid component ≥ 80%) were enrolled. MWA was performed under continuous ultrasound (US) guidance. Before and during the follow-up, the thyroid nodule volume, thyroid function and cosmetic complaints were evaluated. Recurrence is defined by the new blood flow in the total ablation area or/and > 50% increase in nodule volume.

RESULTS

Almost all thyroid nodules were significantly decreased in size after MWA. After 12 months, the average volume of thyroid nodules was decreased from 12.6 ± 15.1 to 3.2 ± 5.7 ml. Of the total 110 patients, 16 cases had recurrence 12 months after MWA, and these patients had a larger initial volume than that of the non-recurrence patients (11.6 ± 14.9 vs. 23.9 ± 12.5, p < 0.01). The recurrence group also demonstrated more irregular blood vessels (1.8 8 ± 1.1 vs. 2.8 5 ± 1.3, p < 0.05), and a lower energy (1575.5 ± 674.3 J/ml vs. 1172.3 ± 454.2 J/ml, p < 0.01). In addition, 81.2% (13/16) of the patients in the recurrence group were adjacent to the vital structures, which is significantly higher than that of the non-recurrence group 28.7% (27/94) (p < 0.01).

CONCLUSIONS

The US-guided MWA results in a satisfactory long-term outcome of the patients with a benign solitary thyroid nodule. We identified three risk factors for recurrence: initial volume, vascularity and the energy per 1 ml reduction in nodular volume.

Microwave ablation for thyroid nodules: a new string to the bow for percutaneous treatments?

BACKGROUND

Thyroid nodules are a fairly common finding in general population and, even if most of them are benign, a treatment can be however necessary. In the last years, non surgical minimally invasive techniques have been developed to treat this pathology, starting from percutaneous ethanol injection (PEI), to laser ablation (LA), radiofrequency ablation (RFA) and, most recently, microwave ablation (MWA).

METHODS

We reviewed all medical literature searching in pubmed.gov the terms "microwave" & "thyroid". We found three original studies concerning MWA treatment, for a total of 263 patients (mean age 51.0 years; range, 15-80 years; male to female ratio 2.55) and 522 nodules.

RESULTS

A total of 522 nodules (338 solid, 22 cystic, 162 mixed) in 263 patients were treated. Studies have shown a mean reduction in volume of thyroid nodules ranging from 45.9% to 65%. No study reported a significant and definitive change in laboratory parameters, except for one case (Heck et al.). No studies have reported major complications after procedure.

CONCLUSIONS

MWA is a new, promising technique among the minimally invasive treatments of thyroid nodules. Actually, the larger diameter of MW antenna seems to be the major limiting factor in the use of this technique. More studies are necessary to evaluate feasibility, safety and efficacy of the procedure.

Detection of the Single-Session Complete Ablation Rate by Contrast-Enhanced Ultrasound during Ultrasound-Guided Laser Ablation for Benign Thyroid Nodules: A Prospective Study

This study aimed to investigate the single-session complete ablation rate of ultrasound-guided percutaneous laser ablation (LA) for benign thyroid nodules. LA was performed in 90 patients with 118 benign thyroid nodules. Contrast-enhanced ultrasound (CEUS) was used to evaluate complete nodule ablation one day after ablation. Thyroid nodule volumes, thyroid functions, clinical symptoms and complications were evaluated 1, 3, 6, 12, and 18 months after ablation. Results showed that all benign thyroid nodules successfully underwent LA. The single-session complete ablation rates for nodules with maximum diameters ≤2 cm, 2-3 cm and ≥3 cm were 93.4%, 70.3% and 61.1%, respectively. All nodule volumes significantly decreased than that one day after ablation (P < 0.05); at the final evaluation, the volume decreased from 6.16 ± 5.21 mL to 0.05 ± 0.01 mL. Thyroid functions did not show significant differences at one month after ablation compared with that before (P > 0.05). Three patients had obvious pain during ablation; one (1.1%) had recurrent laryngeal nerve injury, but the voice returned to normal within 6 months after treatment. Thus, ultrasound-guided LA can effectively inactivate benign thyroid nodules. LA is a potentially viable minimally invasive treatment that offers good cosmetic effects.

Ultrasound-guided percutaneous laser ablation of unifocal T1N0M0 papillary thyroid microcarcinoma: Preliminary results

OBJECTIVES

To evaluate the efficacy and safety of percutaneous laser ablation (PLA) for unifocal T1N0M0 papillary thyroid microcarcinoma(PTMC).

METHODS

A retrospective study was conducted in 30 patients with single PTMC which was diagnosed by fine-needle aspiration biopsy (FNAB). PLA was performed for proper time to achieve adequate ablation zones. The extent of ablation was assessed by contrast-enhanced ultrasound (CEUS) immediately and 7 days after PLA. Complications were recorded. The size and volume of the ablation area and thyroid hormones were measured, and clinical evaluations were performed at 1, 3, 6 and12 months, and every half year thereafter.

RESULTS

The procedure was well tolerated without serious complications. Of the 30 patients, 29 were treated successfully under local anaesthesia in a single session. Only one incomplete ablation was detected by immediate CEUS after PLA, and a second ablation was performed. At the last follow-up, ten (33.3 %) ablation zones had disappeared, and 20 (66.67 %) ablation zones remained as scar-like lesions. No regrowth of treated tumours, local recurrence or distant metastases were detected.

CONCLUSIONS

During the short-term follow-up period, ultrasound-guided PLA appears to be effective and safe for treating solitary T1N0M0 PTMC in selected patients who are ineligible for surgery.

KEY POINTS

• Ultrasound is a useful tool in percutaneous laser ablation (PLA). • PLA is safe for treating papillary thyroid microcarcinoma. • PLA is effective for single papillary thyroid microcarcinoma.

Image-guided thermal ablation of benign thyroid nodules

Benign thyroid nodules are a common disease in the general population. Most often, they are completely asymptomatic and discovered occasionally during routine ultrasound examinations, and do not require any treatment. When thyroid nodules become symptomatic, surgical excision is still considered standard treatment. In the last few years, several experiences in the treatment of benign thyroid nodules through image-guided percutaneous thermal ablation have been reported with encouraging results, so that currently, these treatments are often proposed as first-choice options for patients with symptomatic benign thyroid nodules. In this paper, we discuss the present literature on the topic, focusing on different techniques available for image-guided percutaneous ablation, particularly radiofrequency (RFA), laser (LA), microwave (MWA), and high-intensity-focus ultrasound (HIFU). Little evidence about the efficacy of MWA and HIFU is now available. According to the literature, good results have been obtained with RFA and LA. Regarding RFA, volume reduction after ablative treatment has been found to range from 47 to 84 % at 3-6 months, and from 62 to 93 % at 1 year; LA also seems to be effective in achieving shrinkage of thyroid nodules, with volume reduction from 37 to 81 % at 3-6 months, and from 13 to 82 % at 1-year follow-up. Moreover, applications of advanced image-guidance modality, such as contrast-enhanced ultrasound and virtual navigation with fusion imaging, are discussed.

Laser, radiofrequency, and ethanol ablation for the management of thyroid nodules

PURPOSE OF REVIEW

The majority of benign thyroid nodules are nearly asymptomatic, remain stable in size, and do not require treatment. However, a minority of patients with growing nodules may complain of local symptoms or have cosmetic concerns, and thus seek surgical consultation.

RECENT FINDINGS

The timely use of ultrasound-guided minimally invasive procedures can change the natural history of benign enlarging thyroid nodules. The procedures produce persistent shrinkage of thyroid nodules and are associated with improvement of local symptoms. Among the various procedures, percutaneous ethanol injection represents the first-line treatment for relapsing thyroid cysts. In solid nonfunctioning nodules, laser and radiofrequency ablation produces a more than 50% reduction in nodular volume that remains persistent over several years. For hyperfunctioning nodules, thermal ablation techniques are not appropriate unless radioactive iodine is contraindicated or not accessible.

SUMMARY

MITs are best suited for the management of medium or large-sized nodules that are sonographically well visualized. Conversely, large nodules or nodular goiters that extend into the chest are difficult to treat. MITs are performed in outpatient clinics, are less expensive, and have a lower risk of complications, compared to surgery, and usually do not induce thyroid dysfunction. However, malignancy should be ruled out with a dedicated ultrasound neck assessment and repeat fine needle aspiration of the lesion before treatment.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ASSOCIAZIONE MEDICI ENDOCRINOLOGI MEDICAL GUIDELINES FOR CLINICAL PRACTICE FOR THE DIAGNOSIS AND MANAGEMENT OF THYROID NODULES--2016 UPDATE

Thyroid nodules are detected in up to 50 to 60% of healthy subjects. Most nodules do not cause clinically significant symptoms, and as a result, the main challenge in their management is to rule out malignancy, with ultrasonography (US) and fine-needle aspiration (FNA) biopsy serving as diagnostic cornerstones. The key issues discussed in these guidelines are as follows: (1) US-based categorization of the malignancy risk and indications for US-guided FNA (henceforth, FNA), (2) cytologic classification of FNA samples, (3) the roles of immunocytochemistry and molecular testing applied to thyroid FNA, (4) therapeutic options, and (5) follow-up strategy. Thyroid nodule management during pregnancy and in children are also addressed. On the basis of US features, thyroid nodules may be categorized into 3 groups: low-, intermediate-and high-malignancy risk. FNA should be considered for nodules ≤10 mm diameter only when suspicious US signs are present, while nodules ≤5 mm should be monitored rather than biopsied. A classification scheme of 5 categories (nondiagnostic, benign, indeterminate, suspicious for malignancy, or malignant) is recommended for the cytologic report. Indeterminate lesions are further subdivided into 2 subclasses to more accurately stratify the risk of malignancy. At present, no single cytochemical or genetic marker can definitely rule out malignancy in indeterminate nodules. Nevertheless, these tools should be considered together with clinical data, US signs, elastographic pattern, or results of other imaging techniques to improve the management of these lesions. Most thyroid nodules do not require any treatment, and levothyroxine (LT4) suppressive therapy is not recommended. Percutaneous ethanol injection (PEI) should be the first-line treatment option for relapsing, benign cystic lesions, while US-guided thermal ablation treatments may be considered for solid or mixed symptomatic benign thyroid nodules. Surgery remains the treatment of choice for malignant or suspicious nodules. The present document updates previous guidelines released in 2006 and 2010 by the American Association of Clinical Endocrinologists (AACE), American College of Endocrinology (ACE) and Associazione Medici Endocrinologi (AME).

Treatment efficacy and safety of ultrasound-guided percutaneous bipolar radiofrequency ablation for benign thyroid nodules

OBJECTIVE

To evaluate the therapeutic efficacy and safety of ultrasound-guided percutaneous bipolar radiofrequency ablation (BRFA) of benign thyroid nodules by comparison with a matched untreated control group.

METHODS

The therapeutic efficacy and safety in 35 patients who were subjected to a single session of ultrasound-guided percutaneous BRFA (Group A) for benign thyroid nodules were compared with those in 35 untreated patients (Group B) with benign nodules. The benign nature of all the nodules was confirmed by ultrasound-guided fine-needle aspiration biopsy (FNAB), and all the patients had normal thyroid functions. BRFA was performed with a bipolar electrode (CelonProSurge 150-T20) with an output power of 20 W. Nodule volume, thyroid function and clinical symptoms of all the patients were compared before treatment and during follow-up.

RESULTS

In Group A, the BRFA procedures were completed with a mean time of 10.02 ± 3.30 min (range, 5.47-16.03 min) and with a mean total energy deposition of 10.747 ± 3704 J (range, 5510-17.770 J). The procedures were tolerated well in all the patients without causing any major complications. At the 6-month follow-up, all of the nodule volume decreased significantly (from 8.81 ± 8.66 to 1.59 ± 1.55 ml, p < 0.001) in Group A, whereas the nodule volume increased from 6.90 ± 3.77 to 7.87 ± 3.95 ml in Group B (p < 0.001). All (100%) the 35 nodules in Group A had volume reduction ratios (VRRs) of >50%, among which 3 (8.57%) had VRRs >90%. In Group A, the clinical symptoms of the patients who had symptoms before BRFA disappeared, whereas in Group B, the patients had no resolution of clinical symptoms at the 6-month follow-up.

CONCLUSION

Ultrasound-guided percutaneous BRFA seems to be an effective and safe method for the treatment of benign thyroid nodules. It may gain a wide use in clinical practice.

ADVANCES IN KNOWLEDGE

Based on the comparable efficacy and clinical symptoms between the BRFA and untreated groups, the technique of BRFA can be used as an effective and safe method for the treatment of benign thyroid nodules.

Radiofrequency versus Ethanol Ablation for Treating Predominantly Cystic Thyroid Nodules: A Randomized Clinical Trial

Objective

To compare single-session radiofrequency ablation (RFA) and ethanol ablation (EA) for treating predominantly cystic thyroid nodules (PCTNs).

Materials and Methods

This single-blind, randomized trial was approved by the Institutional Review Board of two centers and informed consent was obtained from all patients before enrollment. Fifty patients with a single PCTN (cystic portion less than 90% and greater than 50%) were randomly assigned to be treated by either RFA (25 patients) or EA (25 patients) at two hospitals. The primary outcome was the tumor volume reduction ratio (%) at the six-month follow-up and the superiority margin was set at 13% (RFA minus EA). Analysis was performed primarily in an intention-to-treat manner. The secondary outcomes were the therapeutic success rate, improvement of symptomatic and cosmetic problems, and the number of major complications.

Results

The mean volume reduction was 87.5 ± 11.5% for RFA (n = 22) and 82.4 ± 28.6% for EA (n = 24) (p = 0.710; mean difference [95% confidence interval], 5.1% [-8.0 to 18.2]), indicating no significant difference. Regarding the secondary outcomes, therapeutic success (p = 0.490), mean symptom (p = 0.205) and cosmetic scores (p = 0.710) showed no difference. There were no major complications in either group (p > 0.99).

Conclusion

The therapeutic efficacy of RFA is not superior to that of EA; therefore, EA might be preferable as the first-line treatment for PCTNs.

Efficacy and Safety of Radiofrequency Ablation Versus Observation for Nonfunctioning Benign Thyroid Nodules: A Randomized Controlled International Collaborative Trial

BACKGROUND

Percutaneous radiofrequency thermal ablation (RFA) has been reported as an effective tool for the management of benign thyroid nodules (BTN). However, large, randomized controlled trials (RCTs) are lacking.

OBJECTIVE

The aims of this study were to assess the volume reduction of BTN after a single RFA performed using the moving-shot technique and to compare the volume reduction obtained in patients treated in two centers with different experience of the moving-shot technique.

METHOD

This study was an international prospective RCT. It was carried out at the Mauriziano Hospital (Turin, Italy) and the Asan Medical Center (Seoul, Korea). Eighty patients harboring solid, compressive, nonfunctioning BTN (volume 10-20 mL) were enrolled. Twenty patients in each country were treated by RFA using a 18-Gauge internally cooled electrode (group A); 20 nontreated patients in each country were followed as controls (group B).

RESULTS

At six months, BTN volume significantly decreased in group A (15.1±3.1 mL vs. 4.2±2.7 mL; p<0.0001), whereas it remained unchanged in group B (14.4±3.3 mL vs. 15.2±3.5 mL). The baseline volume was larger in the Italian series (16.4±2.5 mL vs. 13.9±3.3 mL, p=0.009). However, at six months, there was no significant difference between the Korean group and the Italian group (3.7±2.9 mL vs. 5.5±2.2 mL). Both cosmetic and compressive symptoms significantly improved (3.6±0.5 vs. 1.7±0.4 and 3.6±1.9 vs. 0.4±0.7, respectively; p<0.001). No side effects occurred.

CONCLUSIONS

RFA was effective in reducing the volume of BTN. The outcome was similar in centers with different experience in the moving-shot technique.

Inter-observer variation in ultrasound measurement of the volume and diameter of thyroid nodules

Objective

Thyroid nodule measurement using ultrasonography (US) is widely performed in various clinical scenarios. The purpose of this study was to evaluate inter-observer variation in US measurement of the volume and maximum diameter of thyroid nodules.

Materials and Methods

This retrospective study included 73 consecutive patients with 85 well-defined thyroid nodules greater than 1 cm in their maximum diameter. US examinations were independently performed by using standardized measurement methods, conducted by two clinically experienced thyroid radiologists. The maximum nodule diameter and nodule volume, calculated from nodule diameters using the ellipsoid formula, were obtained by each reader. Inter-observer variations in volume and maximum diameter were determined using 95% Bland-Altman limits of agreement. The degree of inter-observer variations in volumes and the maximum diameters were compared using the Student's t test, between nodules < 2 cm in maximum diameter and those with ≥ 2 cm.

Results

The mean inter-observer difference in measuring the nodule volume was -1.6%, in terms of percentage of the nodule volume, and the 95% limit of agreement was ± 13.1%. For maximum nodule diameter, the mean inter-observer difference was -0.6%, in terms of percentage of the nodule diameter, and the 95% limit of agreement was ± 7.3%. Inter-observer variation in volume was greater in nodules of < 2 cm in maximum diameter, compared to the larger nodules (p = 0.035). However, no statistically significant difference was noted between the two groups regarding maximum nodule diameters (p = 0.511).

Conclusion

Any differences smaller than 13.1% and 7.3% in volume and maximum diameter, respectively, measured by using US for well-defined thyroid nodules of > 1 cm should not be considered as a real change in size.

Advances in nonsurgical treatment of benign thyroid nodules

Ethanol ablation has traditionally been used for treatment of cystic thyroid nodules. Laser ablation and radiofrequency ablation were introduced later and used for treatment of solid thyroid nodules. However, how to select the best treatment modality among the different techniques has, so far, not been determined and causes confusion in clinical practice. Therefore, the necessity for a proper guideline regarding the choice of the preferable treatment modality has been suggested as the use of nonsurgical treatment for benign thyroid nodules has been increasing. This article provides an up-to-date review of nonsurgical treatment of benign thyroid nodules focusing on how to select the best treatment modality according to the composition of thyroid nodules based on the clinical evidence.

Percutaneous Ultrasound-Guided Laser Ablation with Contrast-Enhanced Ultrasonography for Hyperfunctioning Parathyroid Adenoma: A Preliminary Case Series

The study was to evaluate the safety and effectiveness of ultrasound-guided percutaneous laser ablation (pLA) as a nonsurgical treatment for primary parathyroid adenoma. Surgery was contraindicated in, or refused by, the included patients. No lesion enhancement on contrast-enhanced ultrasound immediately after pLA was considered "complete ablation." Nodule size, serum calcium, and parathyroid hormone level were compared before and after pLA. Complete ablation was achieved in all 21 patients with 1 (n = 20) or 2 (n = 1) sessions. Nodule volume decreased from 0.93 ± 0.58 mL at baseline to 0.53 ± 0.38 and 0.48 ± 0.34 mL at 6 and 12 months after pLA (P < 0.05). At 1 day, 6 months, and 12 months after pLA, serum PTH decreased from 15.23 ± 3.00 pmol/L at baseline to 7.41 ± 2.79, 6.95 ± 1.78, and 6.90 ± 1.46 pmol/L, serum calcium decreased from 3.77 ± 0.77 mmol/L at baseline to 2.50 ± 0.72, 2.41 ± 0.37, and 2.28 ± 0.26 mmol/L, respectively (P < 0.05). At 12 months, treatment success (normalization of PTH and serum calcium) was achieved in 81%. No serious complications were observed. Ultrasound-guided pLA with contrast-enhanced ultrasound is a viable alternative to surgery for primary parathyroid adenoma.

Long-term efficacy of ultrasound-guided laser ablation for benign solid thyroid nodules. Results of a three-year multicenter prospective randomized trial

BACKGROUND

The aim of the present trial on ultrasound (US)-guided laser ablation therapy (LAT) of solid thyroid nodules is to assess long-term clinical efficacy, side effects, and predictability of outcomes in different centers operating with the same procedure.

PATIENTS

Two hundred consecutive patients were randomly assigned to a single LAT session (group 1, 101 cases) or to follow-up (group 2, 99 cases) at four thyroid referral centers. Entry criteria were: solid thyroid nodule with volume of 6-17 mL, repeat benign cytological findings, normal thyroid function, no autoimmunity, and no thyroid gland treatment.

METHODS

Group 1: LAT was performed in a single session with two optical fibers, a 1064 nm Nd-YAG laser source, and an output power of 3 W. Volume and local symptom changes were evaluated 1, 6, 12, 24, and 36 months after LAT. Side effects and tolerability of treatment were registered. Group 2: Follow-up with no treatment.

RESULTS

One patient was lost to follow-up in each group. Group 1: Volume decrease after LAT was -49 ± 22%, -59 ± 22%, -60 ± 24%, and -57 ± 25% at 6, 12, 24, and 36 months, respectively (P < .001 vs baseline). LAT resulted in a nodule reduction of >50% in 67.3% of cases (P < .001). Local symptoms decreased from 38 to 8% of cases (P = .002) and cosmetic signs from 72 to 16% of cases (P = .001). Baseline size, presence of goiter (P = .55), or US findings (fluid component ≤ 20% [P = .84], halo [P = .46], vascularization [P = .98], and calcifications [P = .06]) were not predictive factors of a volume decrease > 50%. The procedure was well tolerated in most (92%) cases. No changes in thyroid function or autoimmunity were observed. In group 2, nodule volume increased at 36 months (25 ± 42%; P = .04). The efficacy and tolerability of the procedure were similar in different centers.

CONCLUSIONS

A single LAT treatment of solid nodules results in significant and persistent volume reduction and local symptom improvement, in the absence of thyroid function changes.

The advent of ultrasound-guided ablation techniques in nodular thyroid disease: towards a patient-tailored approach

Surgery is the long-established therapeutic option for benign thyroid nodules, which steadily grow and become symptomatic. The cost of thyroid surgery, the risk of temporary or permanent complications, and the effect on quality of life, however, remain relevant concerns. Therefore, various minimally invasive treatments, directed towards office-based management of symptomatic nodules, without requiring general anaesthesia, and with negligible damage to the skin and cervical tissues, have been proposed during the past two decades. Today, ultrasound-guided percutaneous ethanol injection and thermal ablation with laser or radiofrequency have been thoroughly evaluated, and are accessible procedures in specialized centres. In clinical practice, relapsing thyroid cysts are effectively managed with percutaneous ethanol injection treatment, which should be considered therapy of choice. In solid non-functioning thyroid nodules that grow or become symptomatic, trained operators may safely induce, with a single session of laser ablation treatment or radiofrequency ablation, a 50% volume decrease and, in parallel, improve local symptoms. In contrast, hyperfunctioning nodules remain best treated with radioactive iodine, which results in a better control of hyperthyroidism, also in the long-term, and fewer side-effects. Currently, minimally invasive treatment is also investigated for achieving local control of small size neck recurrences of papillary thyroid carcinoma in patients who are poor candidates for repeat cervical lymph node dissection. This particular use should still be considered experimental.

Levothyroxine or minimally invasive therapies for benign thyroid nodules

BACKGROUND

Thyroid nodules (TN) are common in the adult population. Some physicians use suppressive levothyroxine (LT4) therapy to achieve a reduction in the number and volume of TN. In addition, minimally invasive treatments, such as percutaneous ethanol injection (PEI) sclerotherapy, laser photocoagulation (LP), and microwave (MW), radiofrequency (RF) and high-intensity focused ultrasound (HIFU) ablation, have been proposed, especially for pressure symptoms and cosmetic complaints, as an alternative to surgery. However, the risk to benefit ratio of all treatments for benign TN is currently unknown.

OBJECTIVES

To assess the effects of LT4 or minimally invasive therapies (PEI, LP, and RF/HIFU/MW ablation) on benign TN.

SEARCH METHODS

We identified studies from computerised searches of The Cochrane Library, MEDLINE, EMBASE and LILACS (all performed up to April 2014). We also searched trial registers, examined reference lists of included randomised controlled trials (RCTs) and systematic reviews, and contacted study authors.

SELECTION CRITERIA

We included studies if they were RCTs of LT4, PEI, LP, RF, HIFU or MW therapy in participants with an established diagnosis of benign TN. We excluded trials investigating the prevention of recurrence of thyroid disease after surgery, irradiation or treatment with radioiodine.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data, assessed studies for risk of bias and evaluated overall study quality utilising the GRADE instrument. We assessed the statistical heterogeneity of included studies by visually inspecting forest plots and quantifying the diversity using the I² statistic. We synthesised data using random-effects model meta-analysis or descriptive analysis, as appropriate.

MAIN RESULTS

Thirty-one studies randomised 2952 outpatients to investigate the effects of different therapies on benign TN. Studies on LT4, PEI, LP and RF ablation therapy randomised 2083, 607, 192 and 70 participants, respectively. We found no RCTs of HIFU or MW ablation therapy in benign TN. The duration of treatment varied according to the applied therapies: up to five years for LT4 and one to three PEI ablations, one to three LP sessions and one or two RF sessions. Median follow-up was 12 months for LT4 and six months for minimally invasive therapies. Evidence was of low-to-moderate quality, and risk of performance and detection bias for subjective outcomes was high in most trials.No study evaluated all-cause mortality or health-related quality of life. Only one LT4 study provided some data on the development of thyroid cancer, reporting no abnormal cytological findings. One LP study provided limited information on costs of treatment.LT4 compared with no treatment or placebo was associated with a nodule volume reduction of 50% or more in 16% compared with 10% of participants after 6 to 24 months of follow-up (risk ratio (RR) 1.57 (95% confidence interval (CI) 1.04 to 2.38); P = 0.03; 958 participants; 10 studies; moderate-quality evidence). Pressure symptoms or cosmetic complaints were not investigated in LT4 studies. LT4 therapy was generally well tolerated: three studies provided quantitative data on signs and symptoms of hyperthyroidism, which were observed in 25% of LT4-treated versus 7% of placebo-treated participants at 12 to 18 months of follow-up (269 participants; 3 trials; low-quality evidence).PEI compared with cyst aspiration only was associated with a nodule volume reduction of 50% or more in 83% compared with 44% of participants after 1 to 24 months of follow-up (RR 1.83 (95% CI 1.32 to 2.54); P = 0.0003; 105 participants; 3 studies; low-quality evidence). Improvements in neck compression symptoms after 6 to 12 months of follow-up were seen in 78% of participants receiving PEI versus 38% of those in comparator groups. No reliable summary effect estimate could be established, RR ranged from 1.0 to 3.06 in favour of PEI (370 participants; 3 trials; low-quality evidence). In all trials, participants experienced periprocedural cervical tenderness and light-to-moderate pain usually lasting from minutes to several hours. As a result of the PEI procedure, 26% of participants reported slight-to-moderate pain compared with 12% of those receiving cyst aspiration only (RR 1.78 (95% CI 0.62 to 5.12); P = 0.28; 104 participants; 3 studies; low-quality evidence).One study comparing LP with LT4 showed a nodule volume reduction of 50% or more in favour of LP after 12 months of follow-up in 33% of LP participants versus 0% of LT4 participants, respectively (62 participants; 1 trial; low-quality evidence). A total of 82% of LP-treated versus 0% of untreated participants showed improvements in pressure symptoms after 6 to 12 months of follow-up (RR 26.65 (95% CI 5.47 to 129.72); P < 0.0001; 92 participants; 3 trials; low-quality evidence). Around 20% of LP-treated participants reported light-to-moderate cervical pain lasting 48 hours or more (97 participants; 3 trials; low-quality evidence).One trial with 40 participants, comparing RF with no treatment, resulted in a mean nodule volume reduction of 76% in the RF group compared with 0% of those in the no-treatment group at six months of follow-up (low-quality evidence). These RF-treated participants had fewer pressure symptoms and cosmetic complaints after 12 months of follow-up compared with untreated participants (a 2.8 decrease versus a 1.1 increase on a six-point scale, respectively, with higher values indicating more severe symptoms; low-quality evidence). All participants complained of pain and discomfort during RF, which disappeared when the energy was reduced or turned off (low-quality evidence).

AUTHORS' CONCLUSIONS

No study evaluated all-cause mortality, health-related quality of life or provided systematic data on the development of thyroid cancer. Longest follow-up was five years and median follow-up was 12 months. Nodule volume reductions were achieved by PEI, LP and RF, and to a lesser extent, by LT4. However, the clinical relevance of this outcome measure is doubtful. PEI, LP and RF led to improvements in pressure symptoms and cosmetic complaints. Adverse events such as light-to-moderate periprocedural pain were seen after PEI, LP and RF. Future studies should focus on patient-important outcome measures, especially health-related quality of life, and compare minimally invasive procedures with surgery. RCTs with follow-up periods of several years and good-quality observational studies are needed to provide evidence on the development of thyroid cancer, all-cause mortality and long-term adverse events.

Microwave ablation of benign thyroid nodules

ABSTRACT: 

Microwave ablation (MWA) has become increasingly popular as a minimally invasive treatment for benign and malignant tumors of the liver, lung and kidney. Recently, two studies have attempted to apply the technique to debulk benign thyroid nodules and gained positive results. MWA of benign nodules demonstrated significant volume reductions, while solving nodule-related clinical problems. This article reviews the basic physics, therapeutic indications, patient preparation, devices, procedures, clinical results and complications of thyroid MWA.

Diagnosis of endocrine disease: thyroid ultrasound (US) and US-assisted procedures: from the shadows into an array of applications

In patients with thyroid nodules, ultrasound (US) imaging represents an indispensable tool for assessment of the risk of malignancy. Over approximately four decades, innovative technology and successive improvements have facilitated its entry into the routine management and greatly improved its predictive value. When US features cannot reliably rule out thyroid cancer, US guidance allows a correct and safe sampling also of small or deeply located thyroid lesions. Obtained in this way, cytological or microhistological specimens may reliably define the nature of most thyroid nodules, and the information from histochemical or molecular markers shows promise in the classification of the remaining indeterminate cases. While a prompt surgical treatment can be offered in the minority of suspicious or definitely malignant cases, most individuals warrant only a follow-up. However, at initial evaluation, or over the years, a fraction of these benign lesions may grow and/or become symptomatic. Such cases may benefit from US-guided minimally invasive procedures as an alternative to surgery. Image-guided percutaneous treatments most often achieve relief of neck complaints, are inexpensive, and can be performed on an outpatient basis. The risk of major complications, after adequate training, is very low. Importantly, thyroid function is preserved. Currently, percutaneous ethanol injection for cystic lesions and thermal ablation, with laser or radiofrequency, for solid nodules are increasingly used and disseminated beyond the initial core facilities. In centres with expertise and high patient volume, their use should be considered as first-line treatment alternatives to surgery for selected patients with benign enlarging or symptomatic thyroid lesions.

Interstitial laser photocoagulation (ILP) of benign cystic thyroid nodules--a prospective randomized trial

CONTEXT

Recurrence rate, after aspiration, in cystic thyroid nodules is very high. Interstitial laser photocoagulation (ILP) is a minimally invasive procedure that reduces the need for surgery in patients with a benign solid thyroid nodule.

OBJECTIVE

The aim of the study was to evaluate the efficacy of ILP on remission rates in recurrent, predominantly cystic thyroid nodules.

DESIGN AND METHODS

Forty-four consecutive outpatients with a symptomatic, recurrent, and cytologically benign cystic (cyst volume ≥ 2 mL) thyroid nodule were randomized to a single aspiration with (n = 22) or without (n = 22) subsequent ILP and followed up after 1, 3, and 6 months.

RESULTS

Successful outcome (cyst volume ≤ 1 mL) was obtained in 15 of 22 (68%) patients in the ILP group, compared to 4 of 22 (18%) in the aspiration group (P = .002). In the ILP group, the solid part of the nodule was reduced from a median of 1.8 to 1.0 mL (P = .02). In the aspiration-alone group, neither the cyst volume nor the solid nodule volume was significantly reduced. The reduction in median visual analog score (0-10 cm) for pressure symptoms was significantly higher in the ILP group (from 3.0 to 0.0 cm) than in the aspiration-alone group (from 4.0 to 3.5 cm) (P = .006, between groups). No major side effects occurred, and thyroid function was unaffected throughout.

CONCLUSIONS

US-guided aspiration and subsequent ILP of benign recurrent predominantly cystic thyroid nodules is safe. It significantly reduces recurrence rate, the volume of the solid nodule component, and pressure symptoms. ILP constitutes an important alternative to surgery in such patients.

Single-session treatment of benign cystic thyroid nodules with ethanol versus radiofrequency ablation: a prospective randomized study

PURPOSE

To compare volume reduction of single-session ethanol ablation (EA) and radiofrequency (RF) ablation for cystic thyroid nodule treatment.

MATERIALS AND METHODS

All patients gave written informed consent to participate in this prospective institutional review board-approved study. From May 6, 2010, to August 8, 2011, in this single-institutional, noninferiority trial, 50 patients, each with a single cystic thyroid nodule, were randomly assigned to EA (25 patients; mean age for women, 45.7 years, and for men, 37.5 years) or RF ablation (25 patients; mean age for women, 45.1 years, and for men, 43.7 years) treatment. Internal fluid was aspirated prior to EA or RF ablation. Primary end point was the volume reduction ratio (percentage) at 6-month follow-up; the noninferiority margin was chosen as -8% (EA minus RF ablation). Secondary end points included therapeutic success rate, improvement of symptoms and cosmetic problems, and number of major complications. Analysis was performed primarily in intention-to-treat manner. A one-sided 95% confidence interval (CI) for the mean difference in volume reduction ratio 6 months after treatment was calculated to test for noninferiority. Subsequent superiority comparison of EA with RF ablation on a condition of establishment of the noninferiority of EA to RF ablation was preplanned and used two-sided 95% CI of the outcome difference.

RESULTS

The mean volume reduction was 96.9% in EA and 93.3% in RF ablation (n = 21 for each) (difference, 3.6%; lower bound of the one-sided 95% CI of the difference, 1.2%), thus demonstrating the noninferiority of EA to RF ablation. Two-sided 95% CI of the outcome difference was 0.7% to 6.5%, demonstrating significant superiority of EA to RF ablation. All patients demonstrated therapeutic success (P > .99). Mean symptom and cosmetic scores showed no significant difference in either group (P = .806 and P = .682, respectively). There were no major complications (P > .99).

CONCLUSION

EA may be the first-line treatment modality for cystic thyroid nodules, which has comparable therapeutic efficacy to, but is less expensive than, RF ablation.