Radiofrequency ablation for symptomatic, non-functioning, thyroid nodules: a single-center learning curve

The use of sedimentary metals to assess anthropogenic change, ecological risk, model past and future impacts and identify contaminant sources in the eleven estuaries of Greater Sydney (Australia): A review and critical assessment

The Greater Sydney (Australia) region is dissected by eleven major estuaries comprising a wide range of sizes, sediment and contaminant types, while the catchments also vary in size, land use type, populations size and geology/soils. The magnitude and breadth of the current study are rare and offered an unusual opportunity to provide new information on interactions between source, fate and effect relationships of a highly diverse estuarine-catchment environment using sedimentary metals (Co, Cr, Cu, Ni, Pb and Zn). Advanced methodologies used in this study revealed that although metal concentrations were generally high, ecological risk was surprisingly reduced due to the presence of metal-poor coarse sediment. Stormwater was identified as the dominant source of metals to estuaries of Greater Sydney and relates to development of high-density road networks. Industrial sources, frequently identified as a major contributor to estuarine contamination, was significantly reduced due to the decline of industry through decentralisation and gentrification and because waste is discharged to the sewer system, which is released offshore, or tertiary-treated to the Hawkesbury. Groundwater leachate associated with shoreline reclamation and wetland infilling and metals related to boating activities were important sources of metals impacting local bays and coastal lagoons. Temporal monitoring and unique modelling approaches indicated that the concentration of sedimentary metals is generally declining in these estuaries, (especially for Pb), except for areas with rapidly increasing urban populations. Multivariate statistical modelling was able to differentiate the 11 estuaries on a chemical basis by aligning Cu, Pb, Zn vectors with metal-rich estuaries and also identified catchment attributes (percent area, total yield, anthropogenic yield and population density) normalised to catchment areas as having a major influence on estuarine condition. The new knowledge derived from this study should be used to assess the environmental status of estuaries and to prioritise management actions in future investigations.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

A novel guided approach to radiofrequency ablation of thyroid nodules: the Toronto Sunnybrook experience

Introduction

Thyroid nodules are extremely common being detected by ultrasonography in up to 67% of the population, with current surgical tenet maintaining that lobectomy is required for large symptomatic benign nodules or autonomously functionally nodules resulting in a risk of hypothyroidism or recurrent laryngeal nerve injury even in high volume centres. The introduction of radiofrequency ablation (RFA) has allowed thermal ablation of both benign and autonomously functioning thyroid nodules with minimal morbidity. The moving shot technique is the most well-established technique in performing RFA of thyroid nodules, and has proven to be safe, efficacious, accurate and successful amongst experienced clinicians. The purpose of this article to propose the use of a novel guide when performing RFA of thyroid nodules in clinical practice utilizing the moving shot technique.

Methods

The technique proposed of RFA involves the use of a 10MHz linear ultrasound probe attached to an 18G guide which provides robust in line visualisation of a 7cm or 10cm radiofrequency probe tip (STARmed, Seoul, Korea) utilizing the trans isthmic moving shot technique. A geometric analysis of the guide has been illustrated diagrammatically.

Results

The use of an 18G radiofrequency probe guide (CIVCO Infiniti Plus™ Needle Guide) maintains in line visualisation of the radiofrequency probe over a cross-sectional area up to 28cm2, facilitating efficient and complete ablation of conceptual subunits during RFA of thyroid nodules.

Discussion

Radiofrequency ablation of thyroid nodules can be performed safely and effectively using the novel radiofrequency probe guide proposed which we believe potentially improves both accuracy and overall efficiency, along with operator confidence in maintaining visualisation of the probe tip, and hence we believe provides a valuable addition to the armamentarium of clinicians wishing to embark on performing RFA of thyroid nodules.

Radiofrequency ablation for autonomously functioning nodules as treatment for hyperthyroidism: subgroup analysis of toxic adenoma and multinodular goitre and predictors for treatment success

PURPOSE

Treatment of hyperthyroidism caused by autonomously functioning thyroid nodules (AFTN) with 131I often leads to undesirable hypothyroidism. Radiofrequency ablation (RFA) has emerged as a promising alternative. This retrospective analysis aimed to examine the efficacy of, and postprocedural hypothyroidism after, RFA for AFTN.

METHODS

Patients with hyperthyroidism caused by AFTN and treated with RFA were included if follow-up of at least 1 year was available. Cure was defined as thyroid medication-free biochemical euthyroidism. To predict cure, patient and treatment factors were analysed. A distinction was made between solitary toxic adenoma (STA) and toxic multinodular goitre (TMG).

RESULTS

Forty-eight patients (36 STA, 12 TMG) were included. One year post-RFA cure rate was 72% in STA versus 25% in TMG (p = 0.004). One patient developed hypothyroidism. In 11 patients that remained hyperthyroid, a second RFA was successful in 83% of STA and 40% of TMG patients. At last available follow-up, this amounted to a total cure rate of 81% in STA and 33% in TMG (p = 0.002). In STA, cured patients had a higher baseline TSH and a lower FT3 than non-cured patients (p = 0.026 and 0.031). Cure was observed in 91% of patients when > 2.1 kJ/mL was delivered during RFA, compared to 44% when less energy was administered.

CONCLUSION

The efficacy of RFA was nearly 3 times higher in STA patients compared to TMG. Severity of hyperthyroidism and kJ/mL delivered during RFA predicts cure. Direct comparison to the current standard of care is needed to implement RFA in treatment of hyperthyroidism caused by AFTN.

Can Thyroid Nodules be Managed with Radiofrequency Ablation?

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

[Training of Radiofrequency Ablation for Thyroid Nodules in Korea: Current and Future Perspective]

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. In Korea, RFA for thyroid nodules was first performed in 2002, and a large population study was published in 2008. The Task Force Committee of the Korean Society of Thyroid Radiology (KSThR) developed its first recommendations for RFA in 2009, which were revised in 2012 and 2018. The KSThR guideline was the first guideline for RFA of thyroid nodules worldwide and has become a guideline for physicians to perform thyroid RFA in Korea and other countries around the world. These guidelines have contributed significantly to the establishment and widespread use of RFA worldwide. In addition, since 2015, the KSThR has conducted intensive hands-on courses depending on the level of the participants. In this article, the authors introduce the history of eduction for RFA conducted by the KSThR and describe the learning curve of RFA and current training programs in Korea, along with future directions for training programs.

Risk factors of recurrent thyroid nodules after radiofrequency ablation

Objective

To investigate the risk factors of thyroid nodule recurrence after radiofrequency ablation (RFA). METHODS The medical record information of 120 patients with thyroid nodules admitted to our hospital from June 2019 to April 2022 was retrospectively analysed. All participants received RFA treatment. According to the results of the postoperative thyroid ultrasound examination (USG), the patients were divided into the recurrence group (R, N=16) and the non-recurrence group (NR, N=104). Binary logistic regression analysis was performed to identify the independent risk factors of thyroid nodule recurrence after RFA. The receiver operating characteristic (ROC) curve was used to analyse the value of the forecast of each independent factor and combined model for thyroid nodule recurrence after RFA.

Results

During the follow-up period, 16 patients recurred, and the recurrence rate was 13.33%. Univariate regression analysis showed that whether the nodules are solitary (WNS), nodule diameter (ND), the degree of risk of nodular location (DRN), recurrent laryngeal nerve (RLN) injury were associated with thyroid nodule recurrence after RFA (P<0.05). Binary logistic regression analysis showed that WNS, ND, DRN and RLN injury were independent risk factors for the recurrence of thyroid nodules after RFA (P<0.05). ROC analysis of independent factors and combined model showed that solitary nodules, nodule diameter and nodule location risk degree had diagnostic value, while RLN injury had no predictive value. The combined model is more predictive than the independent factors. Conclusions: The risk factors of recurrent thyroid nodules after radiofrequency ablation are related to WNS, ND, DRN and so on, which should be paid attention to and preventive measures should be taken.

If the price is right: Cost-effectiveness of radiofrequency ablation versus thyroidectomy in the treatment of benign thyroid nodules

BACKGROUND

Radiofrequency ablation is an emerging technology in the United States to treat benign thyroid nodules. The cost-effectiveness of radiofrequency ablation in comparison with traditional thyroidectomy is unknown.

METHODS

A patient-level state transition microsimulation decision model was constructed comparing radiofrequency ablation with lobectomy in the management of benign thyroid nodules. Our base case was a 45-year-old woman with a solitary 30-cm³ nodule. Estimates of health utilities, complications, and mortality were obtained from the literature, and costs were estimated using Medicare reimbursement data. The primary outcomes of interest included total cost, quality-adjusted life years, and incremental cost-effectiveness ratios. All model estimates were subjected to 1-way sensitivity analyses to identify factors that strongly influence cost-effectiveness. A probabilistic sensitivity analysis was run across 1 million simulations to gauge outcome confidence with a willingness-to-pay threshold set at $100,000/quality-adjusted life year.

RESULTS

Radiofrequency ablation was assumed to cost $5,000, with an initial success rate of 78%. Patients with volume reduction ratio <50% underwent a second treatment of radiofrequency ablation. Radiofrequency ablation represented the dominant strategy, yielding 21.31 quality-adjusted life years for a total cost of $16,563 in comparison to lobectomy, which yielded 21.13 quality-adjusted life years for a total cost of $19,262. In a 1-way sensitivity analysis varying the cost of radiofrequency ablation across of range of values, the radiofrequency ablation strategy remained cost-effective until the cost of radiofrequency ablation exceeded $12,330 at willingness-to-pay $50,000 or $17,950 at willingness-to-pay $100,000.

CONCLUSION

Radiofrequency ablation is a cost-effective strategy in the treatment of benign thyroid nodules but is most sensitive to the cost of radiofrequency ablation.