Radiofrequency ablation of benign thyroid nodules: safety and imaging follow-up in 236 patients. Eur Radiol. 2008;18:1244-1250. [PMID: 18286289 DOI: 10.1007/s00330-008-0880-6]

The current state and future perspectives of high intensity focused ultrasound (HIFU) ablation for benign thyroid nodules

High intensity focused ultrasound (HIFU) is a new thermoablation technique used to treat benign thyroid nodules. In this method, the ultrasound beam passes through the patient's skin and focuses very precisely on the target lesion at a distance far from the source of ultrasound generation, making HIFU the only truly non-invasive method of thermoablation developed to date. HIFU is therefore an attractive alternative to surgery and other thermoablative techniques. This review describes the principles of HIFU treatment, the selection of patients suitable for HIFU, the course and effects of treatment, and future perspectives.

Non-Surgical and Non-Radioiodine Techniques for Ablation of Benign Thyroid Nodules: Consensus Statement and Recommendation

Thyroid nodules and cysts are frequently diagnosed in Germany with a prevalence of about 20% in young adults reaching up to 70% in older adults. Surgery is the standard treatment of symptomatic nodules, nodules with suspicion of malignancy and thyroid cancer. Radioiodine treatment is applied for autonomously functioning nodules. During the last years new non-surgical and non-radioiodine techniques have been introduced to treat thyroid nodules. These techniques include ethanol/polidocanol treatment, radiofrequency, microwave, and laser ablation, and high frequency ultrasound ablation. A significant reduction in nodule size could be documented for these techniques in several studies, but long-term outcome data are missing. Until now, there is no general consensus regarding the appropriate indications for these methods. For this reason, the Thyroid Section (German Society for Endocrinology), the Thyroid Working Committee (German Society for Nuclear Medicine), and the German Association of Endocrine Surgeons (CAEK) for the German Society of General and Visceral Surgery (DGAV) reviewed the respective literature, discussed the pro and cons and developed a consensus statement and recommendation to help physicians and patients in their decision making.

A Novel Strategy for Single-Session Ultrasound-Guided Radiofrequency Ablation of Large Benign Thyroid Nodules: A Pilot Cohort Study

Background: Ultrasound-guided radiofrequency ablation (RFA) of thyroid nodules (TNs) is a minimally invasive procedure that has been widely used to induce volume reduction in symptomatic solid benign TNs. The goal of this study was to investigate a novel therapeutic approach for single-session ablation of large thyroid nodules (LTNs, vol > 20 ml). Methods: We performed a pilot cohort study of 21 patients with symptomatic solid benign LTNs (vol > 20 ml), who accepted ultrasound-guided RFA treatment between September 2018 and November 2019. RFA was performed using an 18-gauge internally cooled electrode with ultrasonographic guidance in a single session combined with intraoperative hydrodissection and immediate contrast-enhanced ultrasound (CEUS) to optimize safety and efficacy. Nodule volume was evaluated before ablation and at 1, 3, and 6 months after initial ablation, and all patients were asked to assess the cosmetic score (from 1 to 4) and symptom score (from 0 to 10) before ablation and at every follow-up after ablation. Results: At the 6 month follow-up, there was significant nodule volume reduction, from 27.49 ml ± 7.9 (standard deviation) to 3.82 ml ± 5.02 (p = 0.001). Cosmetic signs (p = 0.001) and pressure symptoms (p = 0.001) were significantly improved. All patients underwent RFA without any major complications, and very few patients developed a change in voice (2/21). However, the changes subsided within 1 month. Almost half of the patients received an additional RFA (11/21) treatment to achieve complete ablation on the intraoperative immediate CEUS evaluation. Conclusion: RFA is effective for treating LTNs (vol > 20 ml) and controlling clinical symptoms with a low complication rate. Patients were satisfied with cosmetic sign and pressure symptom improvement. The intraoperative hydrodissection and immediate CEUS represent a novel therapeutic approach for single-session ablation of LTNs.

Quality of Life in Papillary Thyroid Microcarcinoma Patients Undergoing Radiofrequency Ablation or Surgery: A Comparative Study

Objective: Papillary thyroid microcarcinoma (PTMC) has a good prognosis and a long survival time. Health-related quality of life (HRQoL) is vital for PTMC patients during their survivorship. Ultrasound (US)-guided radiofrequency ablation (RFA), which has high efficacy and safety, is recommended as an alternative treatment to surgery for the patients with low-risk PTMC. However, the assessment of QoL of patients with PTMC has not been specially reported. The purpose of our study was to compare the HRQoL of patients with PTMC who underwent RFA and those who underwent surgery. Methods: From October 2019 to December 2019, 88 PTMC patients were enrolled in our study, including 54 in RFA group and 34 in surgery group. We used three questionnaires which included the 36-item short form health survey (SF-36), thyroid cancer-specific quality of life (THYCA-QOL), and Fear of Progression Questionnaire-Short Form (FoP-Q-SF) for each patient to evaluate their scores of HRQoL. The scores were compared after adjusting for age, sex, medical expense, and follow-up time. Results: According to the SF-36, the scores of the domain for the role limitation due to physical problems and emotional problems (RP, RE) as well as Physical Component Summary (PCS) showed a significant negative linear association between the RFA group and surgery group: RP coefficient [coef]-22.613 [confidence interval (CI) -33.504 to -11.723], p < 0.001, RE (coef: -21.901 [CI -36.737 to -7.064], p = 0.004), and PCS (coef: -8.312 [CI -13.694 to -2.930], p = 0.003). The THYCA-QOL showed that the scores of the surgery group were higher than that of the RFA group regarding scars (coef: 10.246 [CI 1.330 to 19.162], p = 0.025 according to the multivariate analysis), suggesting a higher level of complaint in the surgery group. There was no statistically significant difference in the scores of FoP-Q-SF between the two groups. Conclusions: In patients with PTMC, US-guided RFA offers advantage over surgery in terms of HRQoL, which supports the role of RFA as an alternative strategy to surgery.

Novel Approaches for Treating Autonomously Functioning Thyroid Nodules

Benign thyroid nodules are exceedingly common in the adult population. Only a small percentage of nodules are toxic or autonomously functioning thyroid nodules (AFTNs). The options clinicians have for treating the symptoms of hyperthyroidism include anti-thyroidal medications, radioactive iodine, or surgery. Depending on the patient population treated, these options may not be suitable or have inherent risks that are undesirable to the patient. On the other hand, untreated hyperthyroidism can lead to osteoporosis, atrial fibrillation, emotional lability, and neurological consequences. Thus, we present a review of two novel safe and effective approaches for treating AFTN; one surgical (transoral endoscopic thyroid surgery) and one non-surgical (radiofrequency ablation), as a means for expanding our treatment armamentarium.

Sequential treatment by polidocanol and radiofrequency ablation of large benign partially cystic thyroid nodules with solid components: Efficacy and safety

PURPOSE

The purpose of this study was to retrospectively evaluate the efficacy and safety of a sequential treatment including percutaneous polidocanol sclerotherapy and radiofrequency ablation (RFA) in terms of volume reduction and complication rate in large, benign, partially cystic thyroid nodules with solid components.

MATERIALS AND METHOD

From April 2017 to April 2019, 46 patients with 47 large benign partially cystic thyroid nodules underwent sequential treatment. There were 14 men and 32 women with a mean age of 49.9±11.5 (SD) years (range: 18-75 years). The volume of initial nodules was 12.7±12.3 (SD) mL (range: 2.16-75.62mL). Volume reduction after percutaneous polidocanol sclerotherapy and further RFA was evaluated respectively. Patients had clinical and ultrasound evaluations at a follow-up time of 12.1±5.3 (SD) months (range: 1.5-23.9 months). Technical success and complications were accessed retrospectively.

RESULTS

After unsatisfying results with polidocanol sclerotherapy alone the 46 patients with 47 large benign partially cystic thyroid nodules had further RFA. Mean volume reduction of 47 nodules was 90.5±11.3 (SD) % (range: 43.9-99.3%) one month after RFA, 94.9±6.2 (SD) % (range: 66.9-99.5%) three months after RFA, and 95.8±5.5 (SD) % (range: 71.0-99.8%) six months after RFA. No recurrence or nodule enlargement after RFA was observed at the last follow-up. The complication rate of RFA was 12.5% (8/46 patients), with minor complications only.

CONCLUSIONS

The sequential treatment regimen, including percutaneous polidocanol sclerotherapy and RFA, is an appropriate and safe treatment strategy for large benign partially cystic thyroid nodules with solid components.

Revisiting Rupture of Benign Thyroid Nodules after Radiofrequency Ablation: Various Types and Imaging Features

BACKGROUND

To evaluate the imaging features, clinical manifestations, and prognosis of patients with thyroid nodule rupture after radiofrequency ablation (RFA).

METHODS

The records of 12 patients who experienced thyroid nodule rupture after RFA at four Korean thyroid centers between March 2010 and July 2017 were retrospectively reviewed. Clinical data evaluated included baseline patient characteristics, treatment methods, initial presenting symptoms, imaging features, treatment, and prognosis.

RESULTS

The most common symptoms of post-RFA nodule rupture were sudden neck bulging and pain. Based on imaging features, the localization of nodule rupture was classified into three types: anterior, posterolateral, and medial types. The anterior type is the most often, followed by posterolateral and medial type. Eight patients recovered completely after conservative treatment. Four patients who did not improve with conservative management required invasive procedures, including incision and drainage or aspiration.

CONCLUSION

Thyroid nodule rupture after RFA can be classified into three types based on its localization: anterior, posterolateral, and medial types. Because majority of thyroid nodule ruptures after RFA can be managed conservatively, familiarity with these imaging features is essential in avoiding unnecessary imaging workup or invasive procedures.

Ultrasound-Guided Percutaneous Microwave Ablation for Substernal Goiter: Initial Experience

OBJECTIVES

To preliminarily evaluate the safety, effectiveness, and feasibility of microwave ablation (MWA) for substernal goiter (SSG) in select patients and to provide a relevant treatment reference for further studies.

METHODS

From April 2017 to December 2017, 10 patients with SSG were treated by MWA. All patients were followed for at least 3 months to observe the therapeutic effects and complications. Therapeutic effects were assessed at follow-up for the relief of patients' symptoms, resolution of the cosmetic grade, and volume reduction rate (VRR) of SSG. Possibly related factors for the 3-month VRR of the nodules were analyzed.

RESULTS

The study included 9 female patients and 1 male patient with a mean age ± SD of 56.8 ± 10.1 years (range, 34-70 years). The mean volume of the nodules was 52.9 ± 27.9 mL (range, 23.7-122.6 mL). The nodule volume was significantly reduced at the 3-month follow-up (17.5 ± 9.5 mL; P < .05). The mean 3-month VRR of the index nodule was 66.7% ± 7.1%. A higher ablated portion-to-nodule ratio 1 day after MWA predicted a higher 3-month VRR (Spearman r = 0.646; P = .044). The mean symptom score (from 4.5 ± 1.7 to 1.5 ± 1.0; P = .005) and cosmetic grade (from 3.3 ± 0.5 to 2.2 ± 0.4; P = .004) declined significantly 3 months after the procedure. No complications or unexpected side effects were observed.

CONCLUSIONS

Our preliminary results support the effectiveness and safety of MWA for local control of SSG. This technology can be applied in select patients with SSG who are ineligible for surgery.

Radiofrequency Ablation for Benign Thyroid Nodules: 1-Year Follow-Up in 184 Patients

BACKGROUND

Benign thyroid nodules are common, and must be treated when symptomatic. Non-surgical minimally invasive modalities, including radiofrequency ablation (RFA), have been widely used with good results. The factors related to the efficacy of RFA are still debated. This study was to evaluate the safety, efficacy and related factors of RFA in the treatment of benign thyroid nodules.

METHODS

A retrospective single-center study was conducted on 251 benign thyroid nodules in 184 patients treated with RFA. The procedure was performed under ultrasound (US) guidance using the trans-isthmic approach and the moving-shot technique. Clinical and US examinations were performed at 1, 3, 6, 12 months, and then at 6 month intervals. Study outcomes were volume reduction ratio (VRR) and complications.

RESULTS

There were 153 women and 31 men included in the study. The mean age was 43.9 years. The median initial largest diameter and volume of nodules were 30 mm and 6.18 ml. The median length of follow-up was 12 months. Two minor complications were found. The mean VRR was 66.8; 74.3; and 81% after 3, 6, and 12 months, respectively. Initial solidity was a factor related to the efficacy: cystic nodules had higher VRR compared to solid ones.

CONCLUSIONS

RFA is safe, effective and can be used as a routine treatment for benign thyroid nodules. More prospective multicenter studies with long-term follow-up are required to improve the safety and efficacy of RFA.

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 Efficacy of a Single Session of RFA for Benign Thyroid Nodules: A Longitudinal 5-Year Observational Study

CONTEXT

Radiofrequency ablation (RFA) of benign thyroid nodules has been gaining consensus. However, no solid information on its long-term efficacy is available.

OBJECTIVE

To analyze the long-term results of single-session RFA.

DESIGN

Retrospective longitudinal observational study.

SETTING

Primary care center.

PATIENTS OR OTHER PARTICIPANTS

Adult outpatients who underwent a single-session RFA and posttreatment follow-up of least 3 years.

INTERVENTION

Ultrasound-guided RFA was performed after local anesthesia by "moving-shot" technique. RFA was performed with a median power of 55W and a median time of 14 minutes with an internally cooled 18-gauge electrode with an active 10-mm tip.

MAIN OUTCOME MEASURES

Objective (trend of nodule volume) and subjective (compressive and cosmetic concerns) response to RFA were evaluated. Continuous variables were analyzed by the Wilcoxon and ANOVA test and their correlations by using the Spearman test. Categorical variables were compared by Pearson χ2 test.

RESULTS

Two hundred and fifteen patients were included. An early significant reduction of nodule volume was found at 1 year, lasting up to 5 years. A 67% nodule shrinkage was observed at the end of the observation period. The best response was recorded in nodules below 10 mL (79% reduction early and 81% at 5 years). Patients' symptoms were significantly reduced.

CONCLUSIONS

This study, by demonstrating a durable shrinkage of benign thyroid nodules treated by RFA with an improvement of subjective symptoms, establishes the reliability of RFA as alternative to surgery in the management of thyroid nodules, thus representing a remarkable novelty for clinical practice.

Medullary thyroid carcinoma treated with percutaneous ultrasound-guided radiofrequency ablation

PURPOSE

Minimally invasive image-guided thermal ablation has been proposed as alternative to surgery for treatment of benign thyroid nodules and recurrent differentiated thyroid carcinoma. Here, we report for the first time the use of radiofrequency ablation (RFA) in a patient with non-metastatic medullary thyroid carcinoma (MTC) who did not undergo surgery due to high anesthesiological risk.

METHODS AND RESULTS

A 64-year-old woman was referred to our institution for a routine endocrinological visit. No thyroid-related symptoms were present. She had a history of metabolic, cardiovascular and neurological diseases. On clinical examination, a nodular lesion of about 10 mm was palpable in the right thyroid lobe; ultrasonography (US) confirmed the presence of a 13 mm thyroid nodule in the lower pole of the right lobe, that was hypoechoic and with regular margins. Serum calcitonin (Ctn) level was significantly high (647 pg/mL). Fine-needle aspiration (FNA) of the thyroid nodule was negative for malignant cells, but the marked increase of Ctn level in the FNA wash-out fluid confirmed the diagnostic suspicion of MTC. Since patient refused surgery due to high anesthesiological risk, percutaneous US-guided RFA in single session was performed. At 6-months follow-up the serum Ctn level decreased from the initial value of 647 pg/mL, reaching near-normal range (15 pg/mL), and neck ultrasound showed a complete necrosis of the tumour. Afterward, serum Ctn slowly increased to 49 pg/mL at 15-month follow-up. The US performed at 6 and 12 months of follow-up revealed fibrotic tissue in place of the thyroid nodule, without evidence of cervical lymph-node metastases.

CONCLUSIONS

This clinical case suggests that RFA may be effective and safe for treatment of MTC when surgery cannot be performed.

Single-session treatment of benign thyroid nodules with radiofrequency ablation: Results at 6 months in 24 patients

OBJECTIVE

To evaluate the efficacy and safety of one single-session of radiofrequency ablation (RFA) performed in thyroid benign and predominantly solid nodules.

PATIENTS AND METHOD

Unicentric retrospective study in usual clinical setting that included patients with solid and benign thyroid nodules treated with one single session of RFA and with folllow-up of at at least 6 months after the procedure. RFA was performed as an alternative to surgery in cases of pressure symptoms or nodular growth evidence. Patients were evaluated basally and at one, 3 and 6 months after RFA and also at 12 months if the follow-up was available. In each evaluation efficacy variables were recorded (percentual change from basal volume, percentage of nodules reaching a volume reduction above 50% from baseline, patients with disappearance of pressure symptoms and the possibility of antithyroid drug withdrawal) and safety variables were also registered including minor complications (pain needing analgesic drugs, hematoma) and major complications (voice changes, braquial plexus injury, nodule rupture and thyroid dysfunction).

RESULTS

Twenty-four patients with a follow-up of at least 6 months after RFA were included, 16 of them with more than 12 months of follow-up. Mean nodule volume changed from 25.4±15.5ml basally to 10.7±9.9ml at month 6 (P<.05) and to 9.9±10,4ml at month 12 in 16 nodules. Six months after RFA mean volumetric reduction was 57.5±24% and 65% of the nodules reached a volume reduction above 50% from baseline. Median percentage of reduction at month 6 was 50.4±25.8% for nodules with a basal volume above 20ml (n=13) and 65.3±20.1% for nodules with a lower basal volume (n=11). Pressure symptoms reported in 12 patients disappeared in all cases. Antithyroid drugs could be stopped in 3 of 4 cases treated before RFA. A mild and transient pain responsive to conventional analgesic drugs was recorded in 9 patients during the 24h after the procedure and in 7 a small perithyroid and transient hematoma was observed in the 48 following hours. One major complication was described as a nodule rupture that recovered spontaneously. There were no changes in hormonal values in euthyroid cases.

CONCLUSION

A single session of RFA seems to be an effective and safe procedure in patients with solid thyroid nodules with pressure symptoms or relevant growth evidence. As an outpatient and scarless procedure with no need of general anaesthesia it could become an useful alternative to lobectomy when surgery is refused or in patients at high surgical risk.

Value of monopolar and bipolar radiofrequency ablation for the treatment of benign thyroid nodules

Only a few thyroid nodules are perceived as functional or optically disturbing. If there is a need for action, surgical intervention is the long-term standard by which thermoablative procedures (radiofrequency-, laser-, microwave ablation, high intensity focused ultrasound) must be measured against in terms of safety, effectiveness and patient satisfaction. Prior to intervention assessment of the dignity of the nodule by ultrasound-guided fine needle aspiration is essential for cold and warm nodules, as is the confirmation of an inconspicuous cervical lymph node status. The short-term treatment results of these newer interventions in terms of nodule volume reduction and symptomatic improvement are promising and the general complication rate of the procedures is low. Since functional thyroid parenchyma is preserved, maintaining normal thyroid status is the rule. The procedure is usually performed on an outpatient basis, under local anesthesia and monitoring. The subsequent convalescence is usually very short. Most studies are available on monopolar radiofrequency ablation. Several professional societies have defined indications for radiofrequency ablation (RFA), but these need to be further refined based on practical experience and literature. An acceptable long-term recurrence rate still has to be proven for practically all thermoablative methods, for monopolar RFA limited long-term data are encouraging so far. The recurrence rate as well as patient satisfaction will provide the basis for a meaningful overall cost-benefit analysis in the future.

Radiofrequency Ablation of Thyroid Nodules: A Long-Term Prospective Study of 24 Patients

PURPOSE

To evaluate the volume reduction rate (VRR) of thyroid nodules over a long period of time after radiofrequency (RF) ablation treatment in both solid and mixed nodules; to determine ablation parameters; and to evaluate complications and success rates and safety of RF ablation.

MATERIAL AND METHODS

In this prospective study, 24 patients (83% females and 17% males; age 50.17 ± 13.6 years) underwent ultrasound-guided percutaneous RF ablation of benign thyroid nodules with radiologic follow-up at 1, 3, 6, 12, 24, and 36 months after treatment. All patients presented with compressive or cosmetic complaints and with Thyroid Imaging Reporting and Data System 1 or 2 nodules under ultrasound and were confirmed to be Bethesda Category II after 2 fine-needle aspirations.

RESULTS

A total of 24 nodules (54.2% solid, 37.5% solid predominance, and 8.3% cystic predominance) were included in this study. Significant results in VRR (%) were found at 24 months and 36 months of 69.92 ± 19.23 and 76.84 ± 15.92, respectively. Furthermore, a logarithmic relationship was found when VRR was plotted over time, in both solid and mixed nodules. No correlations were found with any of the ablation parameters. The success rate reached 72.22% at 12 months, and the total complication rate was 16.67% (12.5% minor complications and 4.2% major complications-1 laryngeal nerve palsy), reaching an 83.3% safety.

CONCLUSIONS

RF ablation can be an alternative treatment modality in the management of benign symptomatic thyroid nodules. The results show that it is a safe and effective treatment if trans-isthmic approach and moving-shot techniques are correctly followed.

Does Radiofrequency Ablation Induce Neoplastic Changes in Benign Thyroid Nodules: A Preliminary Study

BACKGROUND

To evaluate the clinical feasibility of radiofrequency ablation (RFA) of benign thyroid nodules along with cytomorphological alteration, and any malignant transformation through biopsy.

METHODS

The data were retrospectively collected between April 2008 and June 2013 and core needle biopsy (CNB) was performed on 16 benign thyroid nodules previously treated using RFA. The parameters of the patients were compared, between the time of enrollment and the last follow-up examination, using linear mixed model statistical analysis.

RESULTS

No atypical cells or neoplastic transformation were detected in the undertreated peripheral portion of treated benign nodules on the CNB specimen. RFA altered neither the thyroid capsule nor the thyroid tissue adjacent to the treated area. On histopathological examinations, we observed 81.2% acellular hyalinization, which was the most common finding. After a mean follow-up period of over 5 years, the mean volume of thyroid nodule had decreased to 6.4±4.2 mL, with a reduction rate of 81.3%±5.8% (P<0.0001).

CONCLUSION

RFA is a technically feasible treatment method for benign thyroid nodules, with no carcinogenic effect or tissue damage of the normal thyroid tissue adjacent to the RFA-treated zone.

Long-Term Outcomes Following Thermal Ablation of Benign Thyroid Nodules as an Alternative to Surgery: The Importance of Controlling Regrowth

Thermal ablation (TA) procedures, such as radiofrequency ablation and laser ablation, are used for the treatment of benign thyroid nodules. Short-term studies (<2 years) have demonstrated that TA is an effective and safe procedure to improve cosmetic or symptomatic problems. However, studies including a longer follow-up period show that treated thyroid nodules can increase in size after 2 to 3 years. Several studies suggest that this results from regrowth at the undertreated nodule margins. Here, we review current data on regrowth after TA and describe factors related to it and possible approaches to prevent it.

Ultrasound-guided radiofrequency ablation (RFA) of benign symptomatic thyroid nodules - initial UK experience

OBJECTIVE

To report on the use of RFA for the treatment of symptomatic benign and autonomously functioning thyroid nodules (AFTNs) in the first reported UK cohort.

METHODS

Patients treated over a 19-month period were retrospectively reviewed. Nodules were assessed pre-treatment and at 1 and 6 months post-treatment. Nodule volume was calculated and cosmetic assessment and thyroid-related quality of life (QoL) scores were recorded at each time point. Thyroid function tests (TFTs) were recorded at all three time points for patients with ATFNs.

RESULTS

46 patients with 50 nodules were treated with no complications. The mean volume reduction 1-month post-treatment was 53 +- 14.9 % ( p < 0.0001). Six month data was available for 31 nodules and showed a mean 67 +- 17.6% vol reduction ( p < 0.0001). Five of the six patients with ATFNs were euthyroid at 1-month post-procedure. 6-month data was available on three of these patients, and all remained euthyroid. The thyroid-related QoL and cosmetic scores also improved. Data from 23 patients was available pre-treatment and at 6 months post-treatment and there was a significant ( p < 0.0001) reduction in QoL score. Pre-treatment, 82 % of nodules were readily visible at rest, decreasing to 12.5 % 6 months after treatment ( p < 0.0001).

CONCLUSIONS

Results align with published data suggesting that RFA is effective at reducing nodule volume and at treating ATFNs and leads to improvement in thyroid-related QoL and cosmetic scores.

ADVANCES IN KNOWLEDGE

This early UK experience demonstrates that day-case radiofrequency ablation can provide safe and effective treatment of benign symptomatic thyroid nodules.

Tumor Volume Doubling Time in Active Surveillance of Papillary Thyroid Carcinoma

Background: Tumor volume (TV) of papillary thyroid carcinoma (PTC) increases exponentially during active surveillance, and the growth rate differs for each patient. TV doubling time (TVDT) is considered a strong dynamic marker for the prediction of the growth rate and progression of the tumor. Methods: This cohort study analyzed 273 PTC patients who underwent active surveillance for more than one year rather than immediate thyroid surgery. TVDT was calculated in each patient, and patients were divided into two groups: rapid-growing (TVDT <5 years) and stable (TVDT ≥5 years). Clinical and initial ultrasonography (US) features between the two groups were compared. Results: The median patient age was 51.1 years (interquartile range [IQR] 42.2-61.0 years), and 76% of the patients were women. The initial TV of PTC was 62.1 mm³ (IQR 28.1-122.8 mm³). During a median of 42 months (IQR 29-61 months) of active surveillance, 10.3% of the patients had a TVDT of less than two years, 5.1% had a TVDT between two and three years, 6.2% had a TVDT between three and four years, 6.6% had a TVDT between four and five years, and 71.8% had a TVDT of five years or more. Patients in the rapid-growing group (77 patients; 28.2%) were significantly younger (p = 0.004) than those in the stable group (196 patients; 71.8%). Being younger than 50 years of age was significantly associated with rapid tumor growth of PTC (odds ratio = 2.31 [confidence interval 1.30-4.31], p = 0.004) in multivariate analysis. In ultrasound findings, macrocalcification was independently associated with rapid tumor growing of PTCs (odds ratio = 4.98 [confidence interval 2.19-11.69], p < 0.001). Conclusions: TVDT is a good indicator for presenting the growing velocity of PTCs during active surveillance. Younger age and macrocalcification in the initial US were associated with rapid-growing PTCs. Determination of TVDT during the early phase of active surveillance may be helpful for the prediction of rapidly progressing PTCs and deciding whether to adopt an early surgical approach.

Successful radiofrequency ablation strategies for benign thyroid nodules

PURPOSE

This study aimed to evaluate the effectiveness of ultrasound (US)-guided radiofrequency ablation (RFA) treatment of benign thyroid nodules in consecutive large number series. To find out whether there is any difference according to the nature of the nodules, nodules were subdivided into two groups of predominantly solid vs. predominantly cystic lesions.

METHODS

We retrospectively analyzed clinical data of thyroid nodules receiving percutaneous RFA treatment in our institution. We subdivided data into two groups according to the nodule's sonographic characteristics. We defined therapeutic success as a volume reduction rate >50% at 6 months post-RFA. The second ablation was performed in case where <50% VRR was achieved at 6 months. The primary endpoint was to identify factors prognosticating response to RFA treatment.

RESULTS

A total of 1000 patients with 1619 thyroid nodules received US-guided RFA treatment. A volume reduction of >50% (therapeutic success) after the first ablation was 78.9% vs. 78.2% (p = 0.439) and 91.4% vs. 93.4% (p = 0.148) after the final ablation for predominantly cystic vs. predominantly solid lesions, respectively, with comparable post-interventional morbidity. RFA sessions were more frequent in the solid group than in the cystic group. Small volume of thyroid nodule (<4 mL) was the only factor significantly associated with therapeutic success in the multivariate analysis (OR 1.848; 95% CI 1.537-2.789, p = 0.030).

CONCLUSION

RFA was effective in reducing the volume of benign thyroid nodules volume with non-inferior result in PS group comparing to PC group and can be considered a principal treatment method for treating benign thyroid nodules, including cystic nodules.

Safety and Efficacy of Radiofrequency Ablation for Nonfunctioning Benign Thyroid Nodules in Children and Adolescents in 14 Patients over a 10-Year Period

PURPOSE

To evaluate the efficacy and safety of radiofrequency (RF) ablation for nonfunctioning benign thyroid nodules in children and adolescents.

MATERIALS AND METHODS

Fourteen pediatric patients (10 female, 4 male; mean age 15.7 ± 2.3 years, range 12-19 years) with nonfunctioning benign thyroid nodules (mean longest diameter 3.7 ± 1.1 cm, range 2.0-5.6 cm) treated with the use of RF ablation from 2005 to 2015 were evaluated. The inclusion criteria for RF ablation therapy were (i) age <20 years, (ii) benign cytological confirmation by ≥2 separate fine-needle aspiration or core needle biopsies, (iii) pressure symptoms or cosmetic problems caused by thyroid nodules, (iv) absence of any suspicious feature as determined with the use of ultrasound (US), (v) normal serum levels of thyroid hormone and thyrotropin, and (vi) follow-up of >6 months. RF ablation was performed with the use of an RF generator and an 18-gauge internally cooled electrode. RF ablation was performed under local anesthesia without conscious sedation or general anesthesia. Changes in nodules on follow-up US, changes in symptomatic and cosmetic scores, and complications arising during or after RF ablation were evaluated.

RESULTS

Mean follow-up period was 36.9 ± 21.7 months (range 6-69 months). At last follow-up visits, mean longest nodule diameter and volume had decreased significantly (3.7 ± 1.1 cm vs 1.4 ± 0.9 cm and 14.6 ± 13.3 mL vs 1.7 ± 4.4 mL; P < 0.001). Both cosmetic and compressive symptoms significantly improved (3.8 ± 0.6 vs 1.4 ± 0.6 and 3.4 ± 1.0 vs 0.1 ± 0.4; P < 0.001). The mean number of ablation sessions was 2.1 ± 1.2 (range 1-5 sessions) and no major complication was encountered during or after RF ablation.

CONCLUSIONS

RF ablation might be a safe and effective treatment modality for nonfunctioning benign thyroid nodules in children and adolescents.

Treatment of thyroid nodules with radiofrequency: a 1-year follow-up experience

PURPOSE

The aim of this study is to assess the effectiveness and safety of radiofrequency ablation (RFA) in debulking benign solid thyroid nodules.

MATERIALS AND METHODS

This is a retrospective review of 77 patients with predominantly solid thyroid nodules treated with RFA in a single center between 2013 and 2016. All patients declined or were not eligible for surgery. Benign proven thyroid nodules causing compressive symptoms and cosmetic concerns were considered for treatment. Nodule volume, thyroid nodule related compressive symptoms, cosmetic concerns and thyroid function were evaluated.

RESULTS

All patients underwent a single treatment session. Mean nodule volume decreased from 17.9 ± 15.6 mL at baseline to 5.2 ± 7.4 after 12 months with a volume reduction ratio (VRR) of 70.9% ± 20.8%. There were no identifiable factors predictive of response to RFA. Median cosmetic and symptom scores of the entire population decreased from 3 [2-4] and 3 [0-10] to 1 [1-3] (p < 0.001) and 0 [0-5] (p < 0.001), respectively. No major complications occurred and RFA did not affect thyroid function when normal.

CONCLUSION

RFA induces substantial volume reduction of predominantly solid thyroid nodules and improves compressive symptoms and cosmetic concerns. RFA does not impact normal thyroid function and has an acceptable safety profile.

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).

Patient satisfaction of radiofrequency ablation for symptomatic benign solid thyroid nodules: our experience for 2-year follow up

Background

The patient satisfaction of symptoms improvement and disease factors that may affect long-term treatment efficacy of radiofrequency ablation (RFA) for non-functioning solid benign thyroid nodules (TNs) over a 2-year follow up study was investigated.

Methods

This retrospective study evaluated 194 non-functioning solid benign TNs of 103 patients. The TNs were categorized as small (≤5 ml), medium (5.1 to 13 ml), intermediate (13.1 to 30 ml) and large (over 30 ml) according to the initial volume of TNs before ablation. Clinical evaluation and contrast-enhanced ultrasound (CEUS) were carried out before ablation and the follow up at 1, 3, 6 months and every 6 months after ablation. All patients were asked to assess the cosmetic score (1–4 scores) and symptom score (0–10 scores) before ablation and every follow up after ablation.

Results

All patients underwent RFA without any major complications. The mean treatment sessions were 1.5 ± 0.6. 98 nodules required a single session (98/194, 50.5%), 87 required two sessions (87/194, 44.9%), 9 required three sessions (9/194, 4.6%). The average follow up months were 16.3 ± 5.6 (range, 6–24 months) and no nodule regrew in our study. After RFA treatment, the TNs volume significantly decreased (P < 0.001). The small group of nodules shrunk larger compared to the medium, intermediate and large groups (P < 0.001). Cosmetic signs and pressure symptoms were significantly improved, particularly in the intermediate and large groups (P < 0.05).

Conclusions

RFA is effective for treating non-functioning solid benign TNs and controlling clinical symptoms with a low complication rate during 2 years follow up. The reduction rate was related to the initial volume of nodules. Patients were satisfied with cosmetic signs and pressure symptoms improvement, particularly in the intermediate and large groups. However, multiple RFA treatments should be used in larger nodules to achieve the desired clinical outcomes.

Microwave Ablation Compared With Laser Ablation for Treating Benign Thyroid Nodules in a Propensity-Score Matching Study

Objective: The efficacy and safety of percutaneous ultrasound-guided microwave and laser ablation (MWA and LA, respectively), for treating benign thyroid nodules (BTNs), were retrospectively compared. Methods: Patients (n = 318) underwent ablation of 328 BTNs. Confounding bias was reduced by propensity-score matching, and finally the MWA and LA groups each comprised 160 nodules. At baseline (before ablation), 3, 6, and 12 months, and every 6 months thereafter, the following were recorded: nodule volume reduction rate (VRR), neck symptom scores, cosmetic scores, complications, and side effects. Results: The baseline characteristics of the MWA and LA groups were comparable. The volumes of all nodules were less at all follow-ups relative to the baseline, as were the symptom and cosmetic scores at postoperative 6 months and thereafter (P < 0.01). At each follow-up, the overall VRRs of the MWA and LA groups were comparable. However, for nodules ≥13 mL, the VRR associated with LA at ≥6 months was significantly greater than that of MWA. The average ablation time for MWA was less than that of LA (P < 0.01). The overall incidences of major complications, minor complications, and side effects were 1.6, 2.2, and 18.4%, respectively, and there were no significant differences between the MWA and LA groups. Conclusion: Percutaneous ultrasound-guided MWA and LA are both safe and effective for the treatment of BTNs. Each can significantly reduce the nodule volume and improve the neck symptoms and appearance of patients, with a low incidence of adverse side effects. The efficiency of MWA is higher than that of LA. For nodules ≥13 mL, MWA may be preferred, but at 6 months and subsequent follow-ups the reduction in volume was greater in patients receiving LA.

Safety and efficiency of ultrasound-guided low power microwave ablation in the treatment of cervical metastatic lymph node from papillary thyroid carcinoma: a mean of 32 months follow-up study

PURPOSE

To evaluate the safety and efficiency of microwave ablation (MWA) with low power of 20 w, respectively, in the treatment of cervical metastatic lymph node (CMLN) from papillary thyroid carcinoma (PTC) with a mean of 32-month follow-up.

METHODS

Eleven patients in total with 24 cervical lymph nodes (LNs) diagnosed with CMLN from PTC underwent MWA at a power of 20 w. We recorded images of the LNs under ultrasound first before MWA and 1, 3, 6, 12, months after MWA, and then every 6 months, respectively. The volumes of the LNs were compared before MWA and at each follow-up point after MWA. The thyroglobulin (Tg) test was performed before MWA and 3 months after MWA.

RESULTS

All patients were successfully treated, and they showed no major complications. Before MWA, the mean volume of the LNs was 364.15 ± 306.89 mm³, which decreased to 234.10 ± 230.34 mm³, 107.51 ± 129.47 mm³, 20.88 ± 39.27 mm³, 3.38 ± 12.74 mm³, and completely disappeared at the follow-up point of 1, 3, 6, 12, and 18 months after MWA, respectively. The mean Tg was 11.81 ± 7.50 ng/ml, a data significantly decreased to 0.43 ± 0.11 ng/ml 3 months after MWA (P = 0.000). In the follow-up period, no recurrent lesions were found.

CONCLUSIONS

For the treatment of CMLN from PTC, low power MWA showed good safety and efficacy. MWA is likely to be a candidate for patients with high risks or who refuse reoperation.

Initial Ablation Ratio: Quantitative Value Predicting the Therapeutic Success of Thyroid Radiofrequency Ablation

BACKGROUND

The aims of this study were to determine a quantitative index, the initial ablation ratio (IAR), representing the amount of ablation, to predict therapeutic success and to evaluate the correlation between the IAR and volume reduction ratio (VRR).

METHODS

Among the patients who underwent radiofrequency ablation (RFA) for the treatment of benign thyroid nodules at the Withsim Clinic between April 2008 and December 2016, 130 patients with 134 nodules were included. The relationship between the IAR and VRR was analyzed at six months, 12 months, and the final follow-up. The relationship between the IAR and final VRR was also analyzed according to the initial nodule volumes.

RESULTS

The mean VRR was 78.7 ± 17.5% (range 23.3-100%) at a mean follow-up period of 22.6 ± 20.1 months (range 3-93 months). The mean IAR was 90.0 ± 11.6% (range 39.1-100%). The correlation coefficient between the IAR and final VRR was 0.65, which indicates a positive correlation (p < 0.001). When the IAR exceeded 70%, it tended to achieve 50% VRR in most cases.

CONCLUSIONS

The IAR is a quantitative indicator of how well the RFA procedures are performed, and it is highly correlated with the VRR. If the IAR is >70%, VRR of >50% may be expected after RFA.

Efficacy and safety of cooled and uncooled microwave ablation for the treatment of benign thyroid nodules: a systematic review and meta-analysis

PURPOSE

To evaluate the effectiveness and safety of microwave ablation (MWA), including cooled MWA (cMWA) and uncooled MWA (uMWA), for the treatment of benign thyroid nodules (BTNs).

METHODS

The databases of MEDLINE, EMBASE and Cochrane library were searched up to 3 Jun, 2018. In this meta-analysis, data of volume reduction rates (VRRs) at the 3-, 6- and 12-month follow-up, and complications are obtained to evaluate the effectiveness and safety of cMWA and uMWA for the treatment of BTNs.

RESULTS

Nine studies involving 1461 patients with 1845 BTNs were included. The pooled VRR at the 3-month follow-up after MWA therapy reached 54.3% (95% CI: 45.3-63.3%, I2 = 97.6%), 73.5% (95% CI: 66.7-80.3%, I2 = 94.9%) at the 6-month follow-up, and 88.6% (95% CI: 84.9-92.4%, I2 = 92.7%) at the 12-month follow-up. The pooled proportions of overall, major and minor complications were 52.4% (95% CI: 29.8-74.9%; I2 = 99.5%), 4.8% (95% CI: 2.7-7.0%; I2 = 55.9%) and 48.3% (95% CI: 31.2-65.4%; I2 = 99.7%). Both cMWA and uMWA achieved similar pooled VRR at the 3-month follow-up (58.4 vs 45.3%, P = 0.07) and pooled proportion of major complications (4.9 vs 5.0%, P = 0.49), while uMWA had higher pooled proportions of overall and minor complications than cMWA (97.8 vs 29.7%, P < 0.01; 97.8 vs 21.0%, P < 0.01), with more patients suffering pain and skin burn after uMWA (100 vs 5.5%, P < 0.01; 47.2 vs 0.2%, P < 0.01).

CONCLUSION

MWA is an effective treatment modality for BTNs. When considering the patient's comfort, cMWA would be a more preferable procedure with less complications.

Summary of the 2017 thyroid radiofrequency ablation guideline and comparison with the 2012 guideline

Radiofrequency ablation (RFA) is a new, minimally invasive modality that serves as an alternative to surgery in patients with thyroid tumors. The Task Force Committee of the Korean Society of Thyroid Radiology developed recommendations for the optimal use of RFA for thyroid tumors in 2012 and revised them in 2017. Herein, we review and summarize the 2017 thyroid RFA guideline and compare it with the 2012 thyroid RFA guideline.

Percutaneous laser ablation for benign and malignant thyroid diseases

Minimally invasive image-guided thermal ablation is becoming increasingly common as an alternative to surgery for the treatment of benign thyroid nodules. Among the various techniques for thermal ablation, laser ablation (LA) is the least invasive, using the smallest applicators available on the market and enabling extremely precise energy deposition. However, in some cases, multiple laser fibers must be used simultaneously for the treatment of large nodules. In this review, the LA technique is described, and its main clinical applications and results are discussed and illustrated.

A propensity score matching study between ultrasound-guided percutaneous microwave ablation and conventional thyroidectomy for benign thyroid nodules treatment

PURPOSE

Our study aims to compare ultrasound (US)-guided percutaneous microwave ablation (PMWA) and conventional thyroidectomy in benign thyroid nodules (BTN) treatment.

MATERIALS AND METHODS

From December 2015 to December 2017, a total of 280 patients with at least one benign thyroid nodule were studied retrospectively, including 156 patients treated with US-guided PMWA and 124 patients treated with conventional thyroidectomy. Propensity score matching was performed to decrease the confounding bias due to retrospective assignment and to balance the pre-operation data of the two groups. A total of 106 pairs (1:1) was created. The operation time, intraoperative blood loss, postoperative hospitalization time, serum levels of interleukin (IL-6), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) 12 h after operation and postoperative complications incidence rate were compared between the two groups. The volume reduction ratio was calculated in the US-guided PMWA group at 1, 3, 6 and 12 months after treatment. Registration number: ChiCTR1800015531.

RESULTS

Significant differences were found between the two groups in levels of CRP, IL-6, and TNF-α after the operation； there were significant differences between the two groups in intraoperative blood loss, operation time, postoperative hospitalization time and postoperative complications rate. The volume reduction ratio at 1, 3, 6 and 12 months after treatment was 15.2%, 47.6%, 67.2% and 79.6%, respectively.

CONCLUSIONS

Our study demonstrated that US-guided PMWA is characterized by a definite therapeutic success rate, good cosmetic effect, slight injury and rapid recovery. US-guided PMWA is an effective technique for benign thyroid nodules treatment．.

Complete endoscopic radical resection of thyroid cancer via an oral vestibule approach

The aim of the present study was to explore the feasibility, safety and effectiveness of complete endoscopic radical resection of thyroid cancer via an oral vestibule approach. A total of 60 patients with unilateral thyroid papillary carcinoma were divided into two groups. Half of them underwent complete endoscopic surgeries via an oral vestibule approach at the Department of Head and Neck Surgery of Fujian Cancer Hospital between November 2014 and December 2016. The other 30 patients underwent traditional open surgeries. All the patients underwent unilateral lobectomy and central neck dissection. Tumor diameter, surgery duration, intraoperative inflation pressure and end-tidal CO₂ flow rate, intraoperative peak value of the partial pressure of end-tidal CO₂, postoperative extubation time, the number of lymph nodes in the specimens of central neck dissection and postoperative complications were noted. From this data, tumor diameter (T stage of tumor), surgery duration, postoperative extubation time, the number of lymph nodes in the specimens of central neck dissection and postoperative complications were compared between the two groups. In the endoscopic group, 1 patient had a tracheal injury, and 1 patient had a submental skin perforation. Furthermore, 17 patients experienced transient numbness of the lower lip, 5 patients experienced an abnormal increase in the partial pressure of end-tidal CO₂, and 2 patients experienced postoperative headache. No recurrent laryngeal nerve injury, postoperative bleeding, or infection was determined. There were no significant differences in all items of the indexes, compared with those patients who underwent open radical surgery. The lymph nodes from region VI may be well exposed and completely removed through this novel procedure with no visible scars, which not only ensured the surgery criterion was met, but also met the cosmetic requirements of the patients. The present study conducted procedures safely by surgeons highly skilled in performing laparoscopic surgery.

Outcomes of Radiofrequency Ablation Therapy for Large Benign Thyroid Nodules: A Mayo Clinic Case Series

OBJECTIVE

To assess the effectiveness, tolerability, and complications of radiofrequency ablation (RFA) in patients with benign large thyroid nodules (TNs).

PATIENTS AND METHODS

This is a retrospective review of 14 patients with predominantly solid TNs treated with RFA at Mayo Clinic in Rochester, Minnesota, from December 1, 2013, through October 30, 2016. All the patients declined surgery or were poor surgical candidates. The TNs were benign on fine-needle aspiration, enlarging or causing compressive symptoms, and 3 cm or larger in largest diameter. We evaluated TN volume, compressive symptoms, cosmetic concerns, and thyroid function.

RESULTS

Median TN volume reduction induced by RFA was 44.6% (interquartile range [IQR], 42.1%-59.3%), from 24.2 mL (IQR, 17.7-42.5 mL) to 14.4 mL (IQR, 7.1-19.2 mL) (P<.001). Median follow-up was 8.6 months (IQR, 3.9-13.9 months). Maximum results were achieved by 6 months. Radiofrequency ablation did not affect thyroid function. In 1 patient with subclinical hyperthyroidism due to toxic adenoma, thyroid function normalized 4 months after ablation of the toxic nodule. Compressive symptoms resolved in 8 of 12 patients (67%) and improved in the other 4 (33%). Cosmetic concerns improved in all 8 patients. The procedure had no sustained complications.

CONCLUSION

In this population, RFA of benign large TNs performed similarly to the reports from Europe and Asia. It induces a substantial volume reduction of predominantly solid TNs, improves compressive symptoms and cosmetic concerns, and does not affect normal thyroid function. Radiofrequency ablation has an acceptable safety profile and should be considered as a low-risk alternative to conventional treatment of symptomatic benign TNs.

Ethanol ablation as a treatment strategy for benign cystic thyroid nodules: a comparison of the ethanol retention and aspiration techniques

PURPOSE

We compared the efficacy and safety of two ethanol ablation techniques-ethanol aspiration and ethanol retention-for benign cystic thyroid nodules.

METHODS

From October 2008 to September 2013, 113 patients who were treated using the ethanol aspiration technique (February 2008 to December 2010) and 108 patients who were treated using the ethanol retention technique (January 2011 to September 2013) were enrolled (male:female ratio, 53:168; mean age, 48.1 years; range, 18 to 80 years). The patient sample had 94 cystic and 127 predominantly cystic thyroid nodules. The volume reduction ratio (VRR) at the last follow-up, improvements in symptoms and cosmetic scores, vascularity, pain, and major complications were evaluated and compared between the ethanol aspiration group and ethanol retention group. We also performed a subgroup analysis according to the proportion of the solid component, in which VRR, symptom and cosmetic scores, and therapeutic success were compared.

RESULTS

No statistically significant difference in VRR was found between the ethanol retention group and the ethanol aspiration group (83.2%±32.8% vs. 86.1%±18.4%, P=0.416) while patients who underwent the retention technique were more likely to experience pain after treatment (P=0.001). VRR, symptom and cosmetic scores, and therapeutic success did not significantly differ between techniques in either group in the subgroup analysis.

CONCLUSION

The ethanol aspiration technique may be preferable to the ethanol retention technique for treating benign cystic and predominantly cystic thyroid nodules, because a comparable VRR can be expected with less pain.

2017 Thyroid Radiofrequency Ablation Guideline: Korean Society of Thyroid Radiology

Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology (KSThR) developed recommendations for the optimal use of radiofrequency ablation for thyroid tumors in 2012. As new meaningful evidences have accumulated, KSThR decided to revise the guidelines. The revised guideline is based on a comprehensive analysis of the current literature and expert consensus.

Cooled tip radiofrequency ablation of benign thyroid nodules: preliminary experience with two different devices

Background

Thyroid nodules are very common in general population. Even if benign, they may require a treatment in case of symptoms or cosmetic concerns. In the last years, minimally invasive treatments alternative to surgery have been developed, in particular ultrasound (US) guided radiofrequency ablation (RFA).

Methods

Twenty-four patients (9 males; 15 females; mean age 57.9 years) were treated and divided in two groups (A and B) according to the RFA needle used (18 gauge needle, AMICA; 17 gauge needle, COVIDIEN). Nodules and patients characteristics, together with procedural data were registered pre-treatment and at 1-month follow-up. US visibility of the needle, volume of the nodules, symptoms and cosmetic concerns, complications were registered.

Results

Visibility of the needle was not significantly different in the two groups (P=0.0787). At 1 month the mean volume of the nodules dropped from 37.1 to 25 mL in group A and from 23.2 to 15.4 mL in group B; shrinkage rate (36.9% and 39.5%, respectively) was not significantly different (P=0.3137). Symptoms decreased from 3.1 to 1.4 in group A and from 4 to 1.6 in group B: no significant differences in reductions were observed (P=0.3305). Cosmetic score decreased from 3.7 to 3.4 in group A and from 3.9 to 3.6 in group B: no significant differences in reductions were observed (P=0.96). Total complication rate (18.2% in group A vs. 23.1% in group B) did not showed significant differences (P=0.5049).

Conclusions

The two systems used in our study resulted equivalent in terms of US needle visibility, efficacy, symptom/cosmetic relief, safety. More patients and a longer follow-up are necessary to confirm our results.

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.