Efficacy of Ethanol Ablation for Benign Thyroid Cysts and Predominantly Cystic Nodules: A Systematic Review and Meta-Analysis

Prevalence and Management of Complications of Percutaneous Ethanol Injection for Cystic Thyroid Nodules: A Systematic Review of Literature and Meta-analysis

Background: We assessed the prevalence of complications from percutaneous ethanol injection (PEI) for benign and cystic thyroid nodules (CTNs) and their management. Methods: We conducted a systematic review with meta-analysis of data from published observational studies on PEI of CTNs. We also included unpublished retrospectively collected data on complications after PEI from all consecutive patients with cytologically benign CTNs who underwent PEI at the Unit of Endocrinology and Metabolic Diseases, AOU University of Campania Luigi Vanvitelli (Naples, Italy) between June 1, 2021, and March 31, 2024. A random effects meta-analysis was performed on the prevalence rate data. Pooled prevalence data were presented with confidence intervals (CIs). The I2 statistic index was used to quantify the heterogeneity. The details of the complications and the management were qualitatively described. Results: The literature search yielded 1189 studies, of which 48 studies were included in the systematic review and meta-analysis, in addition to our institutional experience (3670 CTNs in total). The overall quality of each included study was judged as fair. The prevalence of "Overall" complications of PEI was 32% ([CI 25-40%], I2 92.7%, 967 of 3195 thyroid nodules [TNs]). The prevalence of "Minor" complications of PEI was 32% ([CI 25-40%], I2 92.7%, 952 of 3195 TNs). The prevalence of "Major" complications of PEI was 2% ([CI 1-2%], I2 0%, 22 of 3670 TNs). Sensitivity analyses did not modify the results. The pooled prevalence rate of local pain was 21% (CI [16-27] I2 90.3). Local pain was typically transient and mild, sometimes moderate, and requiring analgesics for few days. The pooled prevalence rate of dysphonia was 1% (CI [1-2], I2 0). Dysphonia was transient and could last from several hours to 12 months after PEI. Conclusions: Complications of PEI for benign and CTNs are relatively common, but most are minor and usually transient, not requiring treatment. Dysphonia was a major complication, but it was uncommon and transient. PEI for CTNs could be considered a generally safe technique.

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.

A clinical practice review of percutaneous ethanol injection for thyroid nodules: state of the art for benign, cystic lesions

Percutaneous ethanol injection (PEI) is a widely used treatment option for cystic and predominantly cystic thyroid nodules. It has several advantages over other treatment modalities. Compared to surgery, PEI is less painful, can be performed in the outpatient setting, and carries less risk of transient or permanent side effects. Compared to other minimally invasive techniques such as radiofrequency ablation (RFA), PEI is less expensive and does not require specialized equipment. PEI performs well in the context of cystic nodules. PEI does not perform as well as other techniques in solid nodules, so its use as a primary treatment is limited to cystic and predominantly cystic thyroid nodules. However, PEI is also being explored as an adjunct treatment to improve ablation of solid nodules with other techniques. Here, we provide a clinical review discussing the genesis, mechanism of action, and patient selection with respect to ethanol ablation, as well as the procedure itself. Predictors of operative success, failure, and common adverse events are also summarized. Altogether, PEI allows impressive volume reduction rates with minimal complications. Several recent studies have also evaluated the long-term impact of PEI up to 10 years after treatment and revealed maintenance of robust treatment efficacy with no undesirable long-term sequelae. Thus, PEI remains the treatment of choice for benign but symptomatic cystic and predominantly cystic thyroid nodules.

Ultrasound-guided ethanol ablation versus the Sistrunk operation as a primary treatment for thyroglossal duct cysts

PURPOSE

This study compared ethanol ablation (EA) with the Sistrunk operation (SO) with regard to feasibility, treatment efficacy, and cost-effectiveness. The goal was to evaluate whether EA could replace SO as a primary treatment modality for thyroglossal duct cysts (TGDCs).

METHODS

This retrospective case-control study included patients with TGDCs who were treated with either EA or SO between 2016 and 2022. The primary outcome variables evaluated were treatment efficacy (as measured by the volume reduction rate [VRR] and treatment success rate), complications, and cost-effectiveness.

RESULTS

A total of 72 patients were enrolled, with 33 in the EA group and 39 in the SO group. The procedure or operation times for the EA and SO groups were 9 and 82 minutes, respectively (P<0.001). At the final follow-up appointment, the VRR was 94.1% for the EA group and 100.0% for the SO group (P<0.001). Treatment success was achieved for 32 patients (97.0%) in the EA group and for all 39 patients (100.0%) in the SO group (P=0.458). The overall complication rates were 0.0% and 17.9% in the EA and SO groups, respectively (P=0.013). The total costs, including all treatment procedures and follow-up ultrasound examinations, were $485 and $1,081.7 for the EA and SO groups, respectively (P<0.001).

CONCLUSION

EA demonstrates superiority over SO in terms of feasibility, safety, and costeffectiveness, while maintaining comparable treatment efficacy. Despite the need for multiple treatment sessions in approximately one-quarter of patients, EA can serve as a primary treatment modality for selected patients with TGDCs, supplanting SO.

[Ultrasound-guided ablation techniques for thyroid lesions]

Ultrasound-guided ablation techniques have been increasingly introduced into routine treatment of thyroid lesions as a complement to existing surgical therapies and radioiodine treatment. In cystic or predominantly cystic lesions instillation therapy (ethanol/polidocanol ablation) has yielded good results. Novel thermal ablation techniques, including radiofrequency ablation (RFA), microwave ablation (MWA), laser ablation (LA) and high intensity focused ultrasound (HIFU), induce irreversible cellular effects by locally applying temperatures ≥ 60 °C to the targeted thyroid region. Lesions causing local symptoms or focal hyperfunctionality can thus be selectively treated under continuous sonographic monitoring. While a considerable body of evidence supports the efficacy and safety of various local ablative techniques, future challenges lie in initiating comparative prospective trials and in standardizing clinical practice, training and continuous quality assessment on a regional and superregional level. In the future, it shall be indicated to include local ablative techniques - so far not known to all patients in Germany - into the informed decision-making process as a suitable alternative or supplement to existing therapies.

Percutaneous ethanol injection in thyroid nodular pathology and metastatic cervical adenopathies: A systematic review, meta-analysis and economic evaluation

BACKGROUND

Percutaneous ethanol injection (PEI) has been shown to be a valuable treatment for thyroid nodular pathology and metastatic cervical adenopathies.

OBJECTIVE

To evaluate the effectiveness, safety, and cost-effectiveness of PEI in thyroid nodular pathology and metastatic cervical adenopathies.

METHODS

A systematic review (SR) using meta-analysis was conducted on the effectiveness and safety of PEI. A SR on cost-effectiveness was also performed. The SRs were conducted according to the methodology developed by the Cochrane Collaboration with reporting in accordance with the PRISMA statement. A cost-minimization analysis was carried out using a decision tree model. Assuming equal effectiveness between two minimally invasive techniques (PEI and radiofrequency ablation (RFA)), the model compared the costs of the alternatives with a horizon of six months and from the perspective of the Spanish National Health System.

RESULTS

The search identified three RCTs (n=157) that evaluated PEI versus RFA in patients diagnosed with benign thyroid nodules: ninety-six patients with predominantly cystic nodules and sixty-one patients with solid nodules. No evidence was found on other techniques or thyroid nodular pathology. No statistically significant differences were observed between PEI and RFA in volume reduction (%), symptom score, cosmetic score, therapeutic success and major complications. No economic evaluations were identified. The cost-minimization analysis estimated the cost per patient of the PEI procedure at €326 compared to €4781 for RFA, which means an incremental difference of -€4455.

CONCLUSIONS

There are no differences between PEI and RFA regarding their safety and effectiveness, but the economic evaluation determined that the former option is cheaper.

Ultrasound-Guided Ethanol Ablation for Thyroglossal Duct Cyst: A Review of Technical Issues and Potential as a New Standard Treatment

The thyroglossal duct cyst (TGDC) is the most common congenital neck mass, accounting for 70-75% of all congenital neck masses. Although the Sistrunk operation has been used as a standard of treatment, it is accompanied by a considerable surgical burden, including the need for general anesthesia, a visible surgical scar on the neck surface, and postoperative complications. Ultrasound-guided ethanol ablation (US-EA) is a minimally invasive and office-based technique that is widely used as a non-surgical treatment for several benign cystic lesions, particularly benign thyroid cysts. Recently, US-EA has also been gaining popularity as a good alternative for TGDC treatment, which is associated with high feasibility, a high safety profile, and favorable treatment outcomes. To our best knowledge, seven studies on the use of EA as a primary treatment option for TGDC have been published since 2011. Although these studies have reported promising results, there is a lack of consensus on several issues regarding the application of EA for TGDC, particularly its detailed techniques and role as a primary treatment. This article aims to provide a comprehensive review of EA for TGDC, addressing technical issues and its possible role as a new standard of treatment for TGDC.

Ultrasound-Guided Ethanol Ablation as a Primary Treatment for Thyroglossal Duct Cyst: Feasibility, Characteristics, and Outcomes

OBJECTIVES

To evaluate the feasibility, characteristics, and outcomes of ultrasound-guided ethanol ablation (US-EA) as a primary treatment for thyroglossal duct cysts (TGDCs).

STUDY DESIGN

Prospective case series.

SETTING

Single center study.

METHODS

The inclusion criteria were as follows: (i) patients with TGDC aged ≥18 years, (ii) benign TGDC in imaging and cytological examinations, and (iii) patients' need for nonsurgical scarless treatment. US-EA was used as the primary treatment strategy. The primary outcome variables were the volume reduction rate (VRR) and cosmetic score at the last follow-up.

RESULTS

We enrolled 28 patients with TGDC. The median TGDC volume at baseline was 6.7 mL. The median procedure time of the US-EA was 6.5 minutes. The median volumes of the cyst aspirate and injected ethanol were 4.0 and 2.0 mL, respectively. Overall, 18, 8, and 2 patients underwent 1, 2, and 3 treatment sessions, respectively. There were no complications. The median VRR was 96.2%, and the treatment success rate was 96.4%. The World Health Organization cosmetic score decreased from 4 (baseline) to 1 (after treatment) in all patients. The subjective grade for cosmetic satisfaction was satisfactory or highly satisfactory in all patients. The VRR, treatment success rate, and the number of treatment sessions did not differ as functions of the characteristics of the TGDC, including the initial volume, septation, debris, or viscosity of the cyst fluid.

CONCLUSION

US-EA was feasible, safe, and effective in patients with TGDC. Therefore, US-EA can be used as a primary treatment for TGDC, evading general anesthesia and surgical scar.

Approach to FNA of Thyroid Gland Cysts

Fine needle aspiration is a well-known procedure for the diagnosis and management of thyroid lesions, representing the first diagnostic tool for the definition of their nature. In clinical practice, a thyroid nodule can be classified as solid, cystic, and partially cystic based on its internal components. Different thyroid imaging reporting systems and cytologic diagnostic systems have focused their attention on solid nodules, which are more frequently linked with a malignant outcome. In fact, numerous papers demonstrated that nodules with microcalcifications, a taller-than-wide shape, hypoechogeneity, and irregular margins, are more likely to be malignant on histology. Nevertheless, according to the literature, the risk of malignancy in a partially cystic thyroid nodule ranges between 3.3 and 17-5%, including, for instance, the possible diagnosis of a cystic papillary thyroid carcinoma and other malignant entities. Therefore, in the current review article, we are going to discuss the approach to thyroid cystic lesions on fine needle aspiration cytology.

Image-Guided Percutaneous Ablation for Primary and Metastatic Tumors

Image-guided percutaneous ablation methods have been further developed during the recent two decades and have transformed the minimally invasive and precision features of treatment options targeting primary and metastatic tumors. They work by percutaneously introducing applicators to precisely destroy a tumor and offer much lower risks than conventional methods. There are usually shorter recovery periods, less bleeding, and more preservation of organ parenchyma, expanding the treatment options of patients with cancer who may not be eligible for resection. Image-guided ablation techniques are currently utilized for the treatment of primary and metastatic tumors in various organs including the liver, pancreas, kidneys, thyroid and parathyroid, prostate, lung, bone, and soft tissue. This article provides a brief review of the various imaging modalities and available ablation techniques and discusses their applications and associated complications in various organs.

Safety and Efficacy of Ultrasound-Guided Radiofrequency Ablation for Benign Nonfunctional Thyroid Nodules in Children: A Retrospective Study of 62 Patients with Over Four Years of Follow-Up

Background: Image-guided radiofrequency ablation (RFA) for benign nonfunctional thyroid nodules in adults has been shown to be effective and safe, but few trials address the use of RFA in children. Therefore, this study was designed to assess the efficacy and safety of RFA application to benign nonfunctional thyroid nodules in children. Methods: A retrospective study of RFA for 70 benign nonfunctional thyroid nodules in 62 children with four-year follow-up was conducted. Volume reduction ratio (VRR), technique efficacy, regrowth rate, symptom score, and cosmetic score were calculated to evaluate the efficacy. Complications and side effects were recorded. Logistic regression analysis was performed to identify risk factors, and subgroup analyses were performed. Results: Patients were followed up for at least four years (59.1 ± 10.5 months, range 48-85 months). After RFA treatment, the VRR and technique efficacy rates were highest at the first year^* (77.5% and 91.4%, respectively) but decreased by four years (55.1% and 81.4%, respectively). The symptom score decreased from 4.0 ± 2.1^* to 0.8 ± 1.6 (Z = -6.82, p < 0.001), and the cosmetic score decreased from 3.3 ± 0.7 to 1.3 ± 0.9 (Z = -7.0, p < 0.001).^* The nodule regrowth rate was 22.9%, of which 56.3% of cases represented loss of efficacy. In the cases of loss of efficacy, 66.7% had greater volume than their initial presentation. Patients who received a second RFA treatment due to loss of efficacy lost efficacy again. Bilateral nodules, low vascularity, and low cystic components were independent risk factors correlating with technique efficacy. Bilateral nodules correlated with low VRR, low efficacy rate, and high regrowth rate. Nodules with a higher proportion of cystic components had higher VRR. The overall complication rate was 4.8%. Conclusions: RFA was effective in reducing the volume of benign nonfunctional thyroid nodules in children, providing significant symptomatic relief with a good safety profile during short- and long-term follow-up. RFA is a good minimally invasive treatment modality for selected pediatric patients, and it may not be appropriate for the treatment of bilateral thyroid nodules in children.

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.