Efficacy and safety of percutaneous ultrasound guided radiofrequency ablation for treating cervical metastatic lymph nodes from papillary thyroid carcinoma

Value of radiofrequency ablation for treating locally recurrent thyroid cancer: a systematic review and meta-analysis for 2-year follow-up

PURPOSE

To evaluate the safety and efficacy of radiofrequency ablation (RFA) in treating locoregional recurrent thyroid cancer (LRTC) after a 2-year follow-up time.

METHODS

PubMed, Embase and Cochrane Library were searched from inception until 20 September 2022 to find studies reporting the safety and efficacy of RFA in LRTC patients after a 2-year follow-up. Two radiologists performed the data extraction and methodological quality assessment according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

We analyzed 6 studies, 229 LRTC patients with 319 locally recurrent tumors were treated with RFA. The mean follow-up time of each study was ≥24 months. The pooled changes in the largest diameter and volume were 7.22 mm (95% confidence interval (CI), 6.35-8.09 mm) and 164.28 mm3 (95% CI, 87.78-240.77 mm3), respectively; the pooled volume reduction rate was 95.03% (95% CI, 87.56-102.49%). The total complete disappearance rate after treatment was 92% (95% CI, 83-100%). The pooled decrease of serum thyroglobulin levels was 0.02 ng/ml (95% CI, -0.00-0.04 ng/ml). The pooled proportion of recurrence rate was 6% (95% CI, 0-13%). The pooled complication rate was 5% (95% CI, 0-10%). The major complications were voice change and hoarseness, only one patient developed permanent vocal cord paralysis; minor complications were cough and pain.

CONCLUSIONS

Ultrasound-guided RFA is an effective and safe treatment for LRTC based on 2-year follow-up results.

The effectiveness and safety of thermal ablation for thyroid carcinoma lymph node metastasis are affected by the diameter of metastatic lymph nodes: A meta-analysis

BACKGROUND

To explore the diameter of lymph nodes with metastatic thyroid carcinoma and the effectiveness and safety of thermal ablation.

METHODS

Several databases were searched for literature on the treatment of thyroid carcinoma metastatic lymph nodes by thermal ablation. A subgroup analysis was performed according to the diameter of the metastatic lymph nodes. The measures included pooled estimates of mean volume reduction, pooled proportions of total disappearance and recurrence, and the pooled proportions of overall complications.

RESULTS

There were 20 studies with 372 patients and 620 metastatic lymph nodes included. Based on the average maximum diameter of the metastatic lymph nodes, they were divided into three groups: A (≤ 10 mm), B (10 < diameter ≤ 20 mm), and C (> 20 mm). The study results indicated a significant decrease in the average volume only in groups A and B. The ratio of tumor disappearance showed that group A had the highest percentage, followed by group B and then group C. The recurrence rates were comparable between groups A and B, but slightly lower than in group C. Moreover, the overall complication rates for the three groups were ranked as follows: group A > group C > group B.

CONCLUSION

Overall, thermal ablation is an effective and safe treatment for thyroid cancer metastatic lymph nodes with diameters of 10-20mm.

Efficacy and safety of percutaneous ultrasound-guided thermal ablation in the treatment of cervical metastatic lymph nodes from papillary thyroid carcinoma

OBJECTIVE

To evaluate the efficacy and safety of percutaneous ultrasound-guided thermal ablation in the treatment of cervical metastatic lymph nodes (LNs) from papillary thyroid carcinoma (PTC).

MATERIALS AND METHODS

A total of 77 patients with 79 LNs ablated by microwave ablation (MWA) or radiofrequency ablation (RFA) between September 2018 and October 2022 were enrolled in this study. After treatment, patients were followed up with measurement of diameters of LNs and serum thyroglobulin (s-Tg) at 1, 3, 6, and 12 months and annually thereafter. The paired t-test was used to compare the changes of s-Tg level, diameters of LNs before and after ablation.

RESULTS

There were no serious complications related to ablation while one case of incomplete ablation in MWA was found during follow-up. The mean longest and shortest diameter of the ablated LNs reduced from 11.6 ± 4.3 mm to 5.0 ± 4.1 mm (p < 0.001), and from 6.1 ± 1.9 mm to 3.0 ± 2.5 mm (p < 0.001) at the last follow-up visit. Besides, the final volume reduction rate (VRR) was 61.8 ± 56.4% (range, -67.0 -100%). The complete disappearance rate was 46.8%, but there were 4 (5.1%) LNs becoming bigger than before. The average s-Tg level was 9.2 ± 26.6 ng/mL, a data significantly decreased to 3.7 ± 7.0 ng/mL at the last follow-up, but no statistical difference was shown.

CONCLUSION

Thermal ablation is an effective and safe modality for the treatment of metastatic LNs from PTC.

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.

Efficacy and safety of ultrasound-guided core needle biopsies (US-CNBs) in cervical lymphadenopathy in patients with suspected head and neck cancer during the COVID-19 pandemic

BACKGROUND

Cervical lymphadenopathy can be benign or malignant. Its accurate diagnosis is necessary to determine appropriate treatment. Ultrasound-guided core needle biopsies (US-CNBs) are frequently used as a percutaneous sampling approach.

OBJECTIVES

Our aim was to identify the efficacy and safety of US-CNBs in 125 patients with cervical lymphadenopathy and clinically suspected head and neck cancer during the COVID-19 pandemic with limited surgical resources.

METHODS

US-CNBs of pathological lymph nodes were performed in 146 lymph nodes on 125 patients. Biopsies were performed ultrasound-guided with a reusable gun core biopsy system and a 10-cm-long 16-G needle. Standard of reference for the histological findings were panendoscopy, clinical and sonographic follow-up, surgical biopsy or a repeat US-CNB.

RESULTS

Adequate material for histologic diagnosis was obtained in 111 patients (89%), of these 83 patients (75%) were diagnosed as malignant, whereas benign lymphadenopathy accounted for 28 patients (25%). Therefore, US-CNB was able to identify malignant or benign lymphadenopathy with an overall accuracy of 88% and 90%, respectively.

CONCLUSIONS

Percutaneous US-CNB is a safe and effective alternative to surgical biopsy in the management of cervical lymphadenopathy in patients with clinically suspected head and neck cancer in a setting with limited resources.

Thermal ablation for cervical lymph node metastasis from papillary thyroid carcinoma: A meta-analysis

BACKGROUND

Traditionally, surgery has been the standard treatment for cervical lymph node metastasis in patients with papillary thyroid carcinoma (PTC). However, thermal ablation is currently recommended by several guidelines. This study aimed to evaluate the efficacy and safety of thermal ablation for lymph node metastasis in patients with PTC.

METHODS

We searched PubMed, Embase, Web of Science, and China National Knowledge Infrastructure databases until March 2022 to collect studies on thermal ablation (including radiofrequency, microwave, and laser ablations) for cervical lymph node metastasis from PTC.

RESULTS

A total of 190 patients were included, ranging from 5 to 39 in each study, with a sex ratio (male/female) ranging from 1/4 to 17/20, an average age ranging from 15.6 ± 3.0 to 62.3 ± 13.2 (yr), and a total of 270 cervical lymph nodes, ranging from 8 to 98. The follow-up results showed that thermal ablation significantly reduced the maximum diameter and volume of metastatic lymph nodes in PTC (P < .01). The pooled complete disappearance rate was 86% (95% confidence interval 79% to 93%). Thyroglobulin levels were significantly lower after surgery (P < .01). No major complications occurred, and the combined voice change rate was as low as 1% [CI 0% to 3%].

CONCLUSION

Our meta-analysis showed that thermal ablation is an effective and safe method for the treatment of cervical lymph node metastases from PTC. Considering the limitations of this study, more prospective, multicenter, large-sample studies are needed in the future.

Comparison of ultrasound-guided radiofrequency ablation versus thyroid lobectomy for T1bN0M0 papillary thyroid carcinoma

OBJECTIVE

To investigate and compare the clinical outcomes between radiofrequency ablation (RFA) and thyroid lobectomy (TL) for T1bN0M0 papillary thyroid carcinoma (PTC).

METHODS

This retrospective study evaluated 283 patients with solitary T1bN0M0 PTC treated with RFA (RFA group, 91 patients) or TL (TL group, 192 patients) from May 2014 to November 2018. The patients were regularly followed up after treatment. Local tumor progression, lymph node metastasis (LNM), recurrent tumor, persistent tumor, recurrence-free survival (RFS), treatment variables (hospitalization, procedure time, estimated blood loss, and cost), complication, and delayed surgery were compared.

RESULTS

During the follow-up (median [interquartile ranges], 50.4 [18.0] months), no significant differences were found in the local tumor progression (4.4% vs 3.6%, p = 1.000), LNM (1.1% vs 2.1%, p = 0.917), recurrent tumor (2.2% vs 1.6%, p = 1.000), persistent tumor (1.1% vs 0%, p = 0.146), and RFS rate (95.6% vs 96.4%, p = 0.816) in the RFA and TL groups. Distant metastasis was not detected. Patients in the RFA group had a shorter hospitalization (0 vs 7.0 [3.0] days, p < 0.001), shorter procedure time (5.6 [2.9] vs 90.0 [38.5] min, p < 0.001), lower estimated blood loss (0 vs 20 [20] mL, p < 0.001), lower cost ($1972.5 [0.1] vs $2362.4 [1009.3], p < 0.001), and lower complication rate (0 vs 12/192 [6.3%], p = 0.015) than those in the TL group. No patients in the RFA group underwent delayed surgery.

CONCLUSIONS

This study revealed comparable 4-year clinical outcomes between RFA and TL for T1bN0M0 PTC in terms of local tumor progression and RFS. As a minimally invasive modality, RFA may be a promising feasible alternative to surgery for the treatment of T1bN0M0 PTC in selected patients after strict evaluation.

KEY POINTS

• No significant difference in local tumor progression and RFS was found between RFA and TL for T1bN0M0 PTC during a median follow-up period of 50.4 months. • Compared with TL, RFA led to a shorter hospitalization, lower estimated blood loss, lower cost, and lower complication rate. • RFA may be a promising feasible alternative to surgery for the treatment of T1bN0M0 PTC in selected patients after strict evaluation.

Evaluating the safety and efficacy of microwave ablation in treatment of cervical metastatic lymph nodes of papillary thyroid carcinoma compared to repeat surgery

OBJECTIVE

To evaluate the safety and efficacy of microwave ablation (MWA) versus repeat surgery for treating metastatic lymph nodes (MLNs) in papillary thyroid carcinoma (PTC).

METHODS

Between July 2017 and October 2020, 67 patients were enrolled in this retrospective study. 19 and 48 patients underwent MWA and repeat surgery, respectively. The primary and secondary endpoints were recurrence-free survival and complication rates, respectively. The largest diameter, volume and volume reduction ratio (VRR) were analyzed before and after MWA. The effects of different ablation powers on the largest diameter, volume and VRR were investigated. Pre and posttreatment variables (e.g., baseline characteristics, serum thyroglobulin [Tg] levels, hospitalization time, treatment costs, recurrence-free survival and complication rates) were compared between groups.

RESULTS

The largest diameter and volume postablation at each follow-up were smaller than the preablation levels (p < 0.05), except at the 1-month follow-up (p > 0.05). The largest diameter, volume, and VRR among the different ablation powers were not significantly different (p > 0.05). The mean serum Tg levels and biochemical remission rates were not significantly different between the groups (p > 0.05). Compared to reoperation, MWA had a shorter hospitalization time and lower treatment cost (p < 0.001). Total and minor complications were higher in the reoperation group (p < 0.05), but major complications were comparable (p > 0.05). The recurrence-free survival rate between groups was not significantly different (p = 0.401). The 1- and 3-year recurrence-free survival rates were comparable between the groups.

CONCLUSIONS

MWA may be a safe and effective alternative to repeat surgery for treating MLNs of PTC in select patients.

Efficacy and Safety of Thermal Ablation for Treating Lymph Node Metastasis From Papillary Thyroid Carcinoma: A Systematic Review and Meta-Analysis

Objective

To evaluate the efficacy and safety of thermal ablation, including radiofrequency ablation (RFA), microwave ablation (MVA), and laser ablation (LA), for treating lymph node metastasis (LNM) from papillary thyroid carcinoma (PTC).

Design and Methods

PubMed and EMBASE were searched for studies reporting the efficacy and safety of thermal ablation for treating LNM in PTC. After selecting the relevant literature (including 11 papers, 208 patients, 412 lymph nodes), the QUADAS-2 tool was used to evaluate its quality. Then, both the fixed-effects and random-effects models combined with subgroup analysis were used to calculate data on volume changes in metastatic lymph nodes and changes in serum thyroglobulin (Tg) levels. We pooled the proportion of major and overall complication rates and complete disappearance rates and used subgroup forest plots and funnel plots for visual representation. Because of publication bias, we also performed a trim-and-filled model for correction. The rate of recurrence and distant metastasis with ablated details were pooled.

Results

In the 11 articles (208 patients and 412 diseased lymph nodes), all thermal ablation methods showed effectiveness in reducing lymph node volume (P = 0.02) and serum Tg levels (P < 0.01) which showed no between-group difference. The pooled proportion of major complications was 0%(95% CI: -0.14; 0.15, P = 1) and the overall complication rate was 5% (95% CI: -0.09; 0.20, P = 1), which revealed no significant difference among modalities. The pooled proportion of the complete disappearance rate was 82% (95% CI: 0.43; 0.96, P < 0.01) and the data with statistical significance which contains RFA and LA showed complete disappearance rate was 59% and 81% respectively.

Conclusion

All thermal ablation methods, including RFA, MWA, and LA, were effective and safe for treating LNM in PTC and were especially suitable for nonsurgical patients. Besides, subgroup analysis showed no significant difference, except for LA is better than RFA in complete disappearance rate.

Ultrasonography-Guided Thermal Ablation for Cervical Lymph Node Metastasis of Recurrent Papillary Thyroid Carcinoma: Is it Superior to Surgical Resection?

AIM

The study aimed to systematically evaluate the safety and efficacy of ultrasonography-guided percutaneous thermal ablation in the treatment of cervical lymph node metastasis (LNM) of recurrent papillary thyroid carcinoma (PTC).

METHODS

PubMed, PubMed Central (PMC), Embase, and Cochrane were examined. The inclusion and exclusion criteria were determined and the relevant data were extracted from the library and other databases for LNM thermal ablation of recurrent PTC. The data were analyzed using Stata15.1, Revman5.3 software, and the standard errors of 95% confidence intervals were estimated using fixed or random effects models. Volume reduction rate (VRR), Serum thyroglobulin (Tg) level before and after thermal ablation, the total complications and major complications incidence were analyzed.

RESULTS

A total of 18 literature articles were included, namely, 10 radiofrequency ablation (RFA), 4 laser ablation (LA), and 4 microwave ablation (MWA). A total of 321 patients had 498 LNM. LNM volume changes before and at the last follow-up of thermal ablation (SMD = 1.04, I² = 8%, 95% CI 0.86-1.21, P <0.0001). The postoperative lymph node VRR was 88.4% (95% CI 77.8-97.3%, I² = 34%, P = 0.14). Tg measurements before and after thermal ablation (SMD = 1.15, 95% CI 0.69-1.60, I² = 84%, P <0.0001). The incidence of total complications was 5.0% (95% CI 3.0-7.0%, I² = 0.0%, P = 0.915), and the incidence of major complications was 4.0% (95% CI 2.0-6.0%, I² = 0.0%, P = 0.888). A total of 131 LNM were located in the central region, and the major complication rate was 12.0% (95% CI 6.0-18.0%, I² = 0.0%, P = 0.653).

CONCLUSION

Ultrasonography-guided thermal ablation is safe and effective in the treatment of LNM of recurrent PTC. The ablation strategy of central LNM needs to be further explored and improved. It can be used as an alternative to surgery for patients with high surgical risk or who refuse resurgery.

SYSTEMATIC REVIEW REGISTRATION

10.37766/inplasy2022.6.0004, identifier INPLASY202260004.

Safety and efficacy of thermal ablation for cervical metastatic lymph nodes in papillary thyroid carcinoma: A systematic review and meta-analysis

BACKGROUND

To evaluate the safety and efficacy of radiofrequency ablation (RFA), microwave ablation (MWA), and laser ablation (LA) for the treatment of cervical metastatic lymph nodes (CMLNs) of papillary thyroid carcinoma (PTC).

METHODS

The Pubmed, EMBASE, Web of Science, and Cochrane Library databases were searched for studies on the safety and efficacy of thermal ablations (RFA, MWA, and LA) for the treatment of CMLNs of PTC until March 30, 2022. A review of 334 potential papers identified 17 eligible papers including 312 patients. Fixed-effects model or random-effects model was used to evaluate the pooled proportions of volume reduction rate (VRR), complete disappearance, and recurrence, and pooled estimates of changes in the largest diameter, volume, and serum Tg after ablation. The pooled proportions of overall and major complications were calculated. Subgroup analysis based on treatment modalities. The heterogeneity among studies was analyzed by using Q statistics and inconsistency index I² . MINORS scale was used to evaluate the quality of the studies.

RESULTS

17 eligible studies were finally identified, including 312 patients and 559 CMLNs. The pooled proportions of VRR, complete disappearance and recurrence of CMLNs were 91.28% [95% confidence interval (CI): 86.60-95.97%], 67.9% [95% CI: 53.1-81.1%] and 7.8% [95%CI: 3.0-14.1%], respectively. The pooled estimates of changes in the largest diameter, volume and serum Tg were 8.12 mm [95%CI: 6.78-9.46 mm], 338.75 mm³ [95%CI: 206.85 -470.65 mm³] and 5.96 ng/ml [95%CI: 3.68-8.24 ng/ml], respectively. The pooled proportions of overall and major complications were 2.9% [95%CI: 0.3-7.1%] and 0.3% [95%CI: 0-1.9%], respectively. Significant between-study heterogeneity was observed for complete disappearance (P<0.01, I² =88.6%), VRR (P<0.001, I² =99.9%), recurrence (P=0.02, I² =47.76%), overall complications (P<0.02, I² =44.8%), and changes in the largest diameter (P < 0.001, I² =82.6%), volume (P<0.001, I² =97.0%), and serum Tg (P < 0.001, I² =93.7%). Subgroup analysis showed heterogeneity of the VRR among the treatment modality (I² range: 84.4-100%). The VRR of MWA was the highest (97.97%), followed by RFA (95.57%) and LA (84.46%) (P < 0.001).

CONCLUSION

All thermal ablations were safe and effective for the treatment of CMLNs of PTC. However, each treatment had significant heterogeneity in VRR. Compared with RFA and MWA, LA was less effective in reducing the volume of CMLNs of PTC.

Ultrasound-Guided Radiofrequency Ablation Versus Thyroid Lobectomy for Low-Risk Papillary Thyroid Microcarcinoma: A Propensity-Matched Cohort Study of 884 Patients

Background: Thermal ablation (TA) has been applied in patients with low-risk papillary thyroid microcarcinoma (PTMC) who refuse surgery or active surveillance (AS). Recently, TA has been proposed as a potential therapeutic option for patients who are suitable for surgery or AS. However, the clinical outcomes of TA versus surgery remains controversial because of a lack of sufficient data. This study aimed to compare the clinical outcomes between radiofrequency ablation (RFA) versus thyroid lobectomy (TL) for low-risk PTMC in a large cohort. Methods: This retrospective study evaluated 884 patients with unifocal low-risk PTMC treated with TL or RFA from June 2014 to March 2018. Among them, 460 patients underwent TL (TL group) and 424 patients, who refused surgery or AS, underwent RFA (RFA group). Patients were regularly followed up after treatment. Local tumor progression, recurrence-free survival (RFS), complications, and treatment variables, including procedure time, estimated blood loss, hospitalization, and cost, were compared after propensity score matching (PSM). Results: After PSM, a total of 332 patients underwent TL (mean ages 43.8 ± 9.5 years) and 332 underwent RFA (mean ages 44.1 ± 9.5 years). During the follow-up (median [interquartile ranges], 48.3 [23.2] months), no significant differences were observed in local tumor progression (1.8% vs. 3.3%, p = 0.209), lymph node metastasis (0.6% vs. 0.6%, p = 1.000), recurrent PTMC (1.2% vs. 2.4%, p = 0.244), persistent lesion (0% vs. 0.3%, p = 0.317), and 4-year RFS rates (98.2% vs. 97.0%, p = 0.223) between the TL and RFA groups. Distant metastasis was not detected. None of the patients who were treated by RFA underwent delayed surgery. Patients undergoing RFA had shorter procedure time (3.4 [2.5] vs. 86.0 [37.0] minutes, p < 0.001), lower estimated blood loss (0 vs. 20 [10.0] mL, p < 0.001), shorter hospitalization (0 vs. 7.0 [3.0] days, p < 0.001), lower cost ($2035.7 [254.0] vs. $2269.1 [943.4], p < 0.001) and lower complication rate (0% vs. 4.5%, p < 0.001) than those treated by TL. The association between treatment modality and recurrence remained nonsignificant after Cox analysis (p = 0.247). Conclusions: This large matched study revealed comparable four-year clinical outcomes between RFA and TL for low-risk PTMC. As a minimally invasive modality, RFA may be a promising alternative to the existing treatment options for low-risk PTMC.

Surgical management of parapharyngeal lymph node metastases from thyroid carcinoma with transcervical approach

BACKGROUND

Parapharyngeal lymph node metastasis is very rare in patients with thyroid carcinoma. In this study, we elucidated on the clinical features, diagnosis, surgical treatment, and outcomes for patients with parapharyngeal lymph node metastases from thyroid carcinoma.

METHODS

Patients with thyroid carcinoma who had been subjected to surgery through the transcervical approach at our institution between April 1999 and January 2019 were retrospectively enrolled in this study.

RESULTS

Parapharyngeal lymph node metastases were successfully resected through the transcervical approach in all the 97 patients. There were 32 treatment-naïve patients, while 65 patients had a history of treatment before parapharyngeal lymph node metastases. All 97 cases of parapharyngeal lymph node metastases were detected by enhanced CT scans. Lateral neck lymph nodes metastases were confirmed in 96 patients. Unexpected postoperative neurological side effects were reported in 11 (11%) patients, including dysphagia in 5 (5%) patients, Horner's syndrome in 2 (2%) patients, glossal deviation in 3 (3%) patients, and asymmetrical mouth in 1 (1%) patient. During the follow-up period, 6 of the 97 patients exhibited parapharyngeal lymph node recurrence (recurrence rate 6.2%). The incidence of distant metastases was 44.3% (43 out of 97). The 5- and 10-year disease-specific survival was 93.4% and 88.9%, respectively.

CONCLUSION

Parapharyngeal lymph node metastases should be considered in patients with widespread cervical lymph node metastases. Enhanced CT scan is one of the best methods for diagnosing such metastases. Surgical resection through the transcervical approach is an effective and safe option for patients with parapharyngeal lymph node metastases from thyroid carcinoma. Moreover, parapharyngeal lymph node metastasis is associated with distant metastases that may lead to poor prognosis.

Ultrasound-guided thermal ablation for cervical lymph node metastasis from thyroid carcinoma: a meta-analysis of clinical efficacy and safety

To evaluate the efficacy and safety of thermal ablation (radiofrequency, microwave, and laser) for treating lymph node metastasis from papillary thyroid carcinoma. A literature search was performed in the Medline, Embase, and Cochrane Library databases. Thirteen studies focusing on the efficacy and safety of thermal ablation for treating lymph node metastasis were eligible. The assessed outcomes were primarily pooled using a random- or fixed-effects model based on the results of the heterogeneity test. A total of 235 patients with 445 metastatic lymph nodes were included. Laser, microwave, and radiofrequency ablation all showed a significant reduction in maximum diameter and volume of metastatic lymph nodes (P < 0.0001). Microwave ablation had a higher volume reduction rate (99%; 95% CI, 98-100%) comparing to the other two techniques (P = 0.0057). For all ablations, the pooled completely disappear rate was 70% (95% CI, 45-87%) and the recurrent rate was 3% (95% CI, 2-5%). Thyroglobulin levels significantly decreased (P < 0.0001). No major complications were encountered; the pooled proportion of voice change was low to 4% (95% CI, 2-7%). Thermal ablation is acceptable treatments to manage lymph nodes metastasis from papillary thyroid carcinoma in terms of efficacy and safety for non-surgical candidates.

Long-term follow-up results of PTMC treated by ultrasound-guided radiofrequency ablation: a retrospective study

OBJECTIVES

To confirm the long-term efficacy and safety of radiofrequency ablation (RFA) for low-risk papillary thyroid microcarcinoma (PTMC).

METHODS

We retrospectively reviewed data of 102 primary papillary thyroid carcinoma patients (82 women, 20 men; mean age: 43 [19] years) treated with radiofrequency ablation and thyroid-stimulating hormone (TSH) suppression therapy before December 2018. All patients were at high surgical risk or refused surgery. They were followed up at 1, 3, 6, 9, and 12 months and every 6-12 months thereafter using ultrasound and contrast-enhanced ultrasound. The volume and volume reduction ratio was calculated. Recurrence and lymph node or distant metastasis were evaluated.

RESULTS

The mean initial tumor diameter was 0.50 (0.29) cm; the mean initial volume was 0.06 (0.09) mL. At 1, 3, 6, 9, 12, 24, 36, 48, and 60 months after RFA, complete resorption rates were 0, 0, 9.8 (10/102), 33.3 (34/102), 91.2 (93/102), 96.1 (98/102), 99 (101/102), 100, and 100%, respectively. Two patients had developed ipsilateral neck lymph node metastasis in regions IV and VI at 30- and 18-month follow-ups, respectively. After RFA, 3/102 patients (2.9%) developed hoarseness-the main side effect. No life-threatening or delayed complications occurred. The TSH value in the initial period was 0.06 (0.02) µIU/mL; the rate of reaching the TSH target was 85.7%. The TSH value at follow-up was 1.47 (0.91) µIU/mL; the compliance rate was 99.3%.

CONCLUSIONS

Ultrasound-guided RFA for PTMC is highly effective and safe. RFA can serve as a minimally invasive treatment for PTMC patients who refuse surgery or active surveillance.

Ultrasound-guided implantation of radioactive 125I seed in radioiodine refractory differentiated thyroid carcinoma

BACKGROUND

Treatment for radioiodine refractory differentiated thyroid carcinoma (RR-DTC) is challenging. The purpose of this study was to assess the efficacy and safety of ultrasound-guided implantation of radioactive ¹²⁵I-seed in radioiodine refractory differentiated thyroid carcinoma.

METHODS

Thirty-six cervical metastatic lymph nodes (CMLNs) diagnosed with RR-DTC from 18 patients were enrolled in this retrospective study. US and contrast-enhanced ultrasound (CEUS) examinations were performed before implantation. Follow-up comprised US, CEUS, thyroglobulin (Tg) level and routine hematology at 1-3, 6, 9 and 12 months and every 6 months thereafter. The volumes of the nodules were compared before implantation and at each follow-up point. The volume reduction rate (VRR) of nodules was also recorded.

RESULTS

The median volume of the nodules was 523 mm³ (148, 2010mm³) initially, which decreased significantly to 53mm³ (0, 286mm³) (P < 0.01) at the follow-up point of 24 months with a median VRR as 95% (86,100%). During the follow-up period (the range was 24-50 months), 25 (69%) nodules had VRR greater than 90%, of which 12 (33%) nodules had VVR ≈ 100% with unclear structures and only ¹²⁵I seed images were visible in the US. At the last follow-up visit, the serum Tg level decreased from 57.0 (8.6, 114.8) ng/ml to 4.9 (0.7, 50.3) ng/ml, (P < 0.01).

CONCLUSION

US-guided ¹²⁵I seed implantation is safety and efficacy in treating RR- DTC. It could be an effective supplement for the comprehensive treatment of thyroid cancer.

Comparison of thermal ablation and routine surgery for the treatment of papillary thyroid microcarcinoma: a systematic review and Meta-analysis

BACKGROUND

Thermal ablation (TA), as an alternative to surgery, has shown some benefits in the treatment of papillary thyroid microcarcinoma (PTMC) patients, especially for those who are at high risk for surgery or refuse surgery. We performed a systematic review and meta-analysis to evaluate the efficiency, safety, and economy of TA, compared with those of routine surgery (RS), for the treatment of PTMC.

METHODS

PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang, and VIP databases were retrieved from inception to 10 January 2020 to identify relevant original studies on comparison of TA and RS for treatment of PTMC. The recurrence rate, recurrence-free survival (RFS), complication rate, operation time, postoperative length of stay, and cost during the perioperative period were extracted as main indices. The pooled standardized mean difference (SMD) or odds ratio (OR) with 95% confidence intervals (CI) were calculated and analyzed. Chi-square test and I ² statistic were applied to determine the heterogeneity among studies. The sensitivity analysis was applied to explore the origin of heterogeneity, and the publication bias was evaluated by Egger's test.

RESULTS

Seven retrospective studies with a total of 867 patients met the eligibility criteria and were included in the final meta-analysis. Our study demonstrated that TA showed significant reduction in complication with a pooled OR 0.24 (95% CI 0.13 to 0.43), postoperative length of stay with a pooled SMD -3.14 (95% CI -4.77 to -1.51) and cost during the perioperative period with a pooled SMD of -1.69 (95% CI -3.18 to -0.20). It also demonstrated that both TA and RS had similar pooled proportion of recurrence of OR 0.93 (95% CI 0.38 to 2.30) and recurrence-free survive (RFS). The sensitivity analysis showed that each included study had no significant effect on the results and the results were stable and reliable. The Egger's test demonstrated publication bias was acceptable.

CONCLUSIONS

TA may not be oncologically inferior to RS, and it is a relatively safe and economical alternative for the treatment of PTMC.

Feasibility and safety of percutaneous computed tomography guided radiofrequency ablation of lymph nodes in oligometastatic patients: a single center's experience

OBJECTIVES

To retrospectively evaluate feasibility and safety of CT-guided percutaneous radiofrequency ablation (RFA) of metastatic lymph nodes (LN) in terms of achieving local tumor control.

METHODS

Institutional database research identified 16 patients with 24 metastatic LNs who underwent percutaneous CT-guided radiofrequency ablation. Mean patient age was 66.6 ± 15.70 years (range 40-87) and male/female ratio was 8/8. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics and RFA technique were evaluated. Technical and clinical success on per tumor and per patient basis as well as complication rates were recorded.

RESULTS

Mean size of the treated nodes was 1.78 ± 0.83 cm. The mean number of tumors per patient was 1.5 ± 0.63. The mean procedure time was 56.29 ± 24.27 min including local anesthesia, electrode(s) placement, ablation and post-procedural CT evaluation. Median length of hospital stay was 1.13 ± 0.34 days. On a per lesion basis, the overall complete response post-ablation according to the mRECIST criteria applied was 75% (18/24) of evaluable tumors. Repeat treatment of an index tumor was performed on two patients (three lesions) with complete response achieved in 87.5% (21/24) of evaluable tumors following a second RFA. On a per patient basis, disease progression was noted in 10/16 patients at a mean of 13.9 ± 6.03 months post the ablation procedure.

CONCLUSION

CT-guided percutaneous RFA for oligometastatic LNs is a safe and feasible therapy.

ADVANCES IN KNOWLEDGE

With this percutaneous therapeutic option, metastatic LNs can be eradicated with a very low complication rate.

Value of contrast-enhanced ultrasonography in radiofrequency ablation of secondary hyperparathyroidism

Objectives

The purpose of the current study was to determine the performance of contrast-enhanced ultrasound (CEUS) in the assessment of radiofrequency ablation (RFA) of hyperplastic parathyroid glands due to secondary hyperparathyroidism (SHPT).

Methods

Thirty-two patients, each with ≥4 hyperplastic parathyroid glands due to SHPT, underwent RFA via hydro-dissection. CEUS was performed in each patient before and during RFA. The patients in whom the intact parathyroid hormone (iPTH) level did not decrease to 300 pg/ml were examined by CEUS. The iPTH, serum calcium, and serum phosphorus levels before and after RFA were compared.

Results

Ablation was achieved in all patients (131 ablated glands). The volume of the glands was 479.88 ± 549.3mm³. The pre-operative and day 1 post-operative iPTH levels were 2355 ± 1062 and 292.7 ± 306.8 pg/ml, respectively. Three nodules in three patients showed little enhancement on CEUS on post-operative day 1. The iPTH level was <300 pg/mL on post-operative day 1 in 23 patients, which indicated complete ablation; follow-up evaluations were therefore performed. The pre- and post-operative iPTH levels in the 23 patients were 2113 ± 787.2 and 106.2 ± 84.62 pg/ml, respectively (p < 0.05), and the 6- and 12-month post-operative iPTH levels were 111.1 ± 56.57 and 117.6 ± 97.08 pg/ml, respectively (p > 0.05).

Conclusions

CEUS-guided RFA is effective and feasible for the treatment of ≥4 hyperplastic parathyroid glands. CEUS was shown to assist the surgeon before, during, and after RFA. CEUS on post-operative day 2, but not immediately post-operatively, was shown to accurately reflect gland perfusion.

Efficacy and Safety of Thermal Ablation for Solitary T1bN0M0 Papillary Thyroid Carcinoma: A Multicenter Study

BACKGROUND

Ultrasound-guided thermal ablation plays an important role in the management of thyroid disease. The objective of this study was to evaluate the feasibility, efficacy, and safety of thermal ablation for patients with solitary T1bN0M0 papillary thyroid carcinoma (PTC) who are ineligible for or unwilling to undergo surgery.

MATERIALS AND METHODS

Data pertaining to 172 patients (38 males and 134 females) who received thermal ablation therapy at 12 hospitals between April 2015 and March 2020 were retrospectively analyzed. The mean duration of follow-up was 24.9 ± 14.1 months (range, 12-60). The technical feasibility, technical success, efficacy, and safety of treatment were analyzed. Postablation tumor size at various time points was compared with preablation measurement.

RESULTS

All patients selected for thermal ablation received enlarged ablation, according to contrast-enhanced ultrasound postablation. The maximum diameter and volume of ablation zone at 6, 12, 18, 24, 36, and 48 months postablation were significantly smaller than those recorded preablation (P < 0.05 for all). At the most recent follow-up, 106 (61.6%) tumors had completely disappeared. The rate of lymph node metastasis was 0.6% (1/172) and the incidence of new tumors was 1.2% (2/172). The overall complication rate was 5.2% (9/172) (major complications: 4.6% [8/172]; minor complications: 0.6% [1/172]). All major complications were relieved within 4 months postablation.

CONCLUSION

Thermal ablation may be a feasible, effective, and safe treatment option for patients with solitary T1bN0M0 PTC who are ineligible for or unwilling to undergo surgery. It may provide a novel treatment option for selected patients.

Radiofrequency Ablation for Cervical Metastatic Lymph Nodes in Children and Adolescents With Papillary Thyroid Carcinoma: A Preliminary Study

OBJECTIVE

To evaluate the safety and efficacy of radiofrequency ablation (RFA) for metastatic lymph nodes (LNs) in children and adolescents with papillary Thyroid Carcinoma (PTC).

MATERIALS AND METHODS

From December 2014 to March 2018, 10 metastatic LNs(mean volume 0.30 ± 0.38 ml, range 0.06-1.23ml) in 5 children and adolescents (3 females, 2 males; mean age 15.60 ± 2.97 years, range 12-19 years) with PTC treated by RFA were evaluated in this study. The mean number of surgical procedures performed before RFA was 1.2 (range 1-2) and the mean number of treated metastatic LNs per patient was 2 (rang 1-3). RFA was performed with an 18-gauge bipolar RF applicator under local anesthesia. Follow-up consisted of US and serum thyroglobulin (Tg) level at 1, 3, 6, 12 months and every 12 months thereafter.

RESULTS

All the patients were well tolerant to RFA procedure and no procedure-related complications occurred. During a mean follow-up time of 52.00 ± 21.44 months, the initial volume of LNs was 0.30 ± 0.38 ml, which significantly decreased to 0.01 ± 0.03 ml (P = 0.005) with a mean VRR of 99.28 ± 2.27%. A total of 9 metastatic LNs (90.00%) completely disappeared. After RFA, 2 patients developed newly metastases. One patient had additional RFA. The other one with multiple LN metastases underwent total thyroidectomy with central neck dissection.

CONCLUSION

As a less invasive and effective technique, RFA may provide another alternative to the existing therapeutic modalities for cervical metastatic LNs in children and adolescents with PTC.

Efficacy and safety of microwave ablation for cervical metastatic lymph nodes arising post resection of papillary thyroid carcinoma: a retrospective study

Purpose: To evaluate the efficacy and safety of microwave ablation (MWA) for cervical metastatic lymph nodes (LNs) post resection of papillary thyroid cancer (PTC).Materials and methods: From November 2015 to November 2018, 14 patients with 38 cervical metastatic LNs treated by MWA were included in this retrospective study. Wilcoxon signed rank test was used to compare the changes of LN and serum thyroglobulin levels pre- and post-ablation.Results: The technical success rate in this study was 100% (38/38). The mean follow-up time was 23.6 ± 9.3 months. On pre-ablation contrast-enhanced ultrasound, 25 LNs showed high-enhancement, 8 LNs showed iso-enhancement, and 5 LNs showed low-enhancement. The median largest diameter of LNs at pre-ablation and 3, 6, 9, 12, 18, 24, and 36 months post-ablation was 11.5 mm and 9.5, 9.0, 8.0, 8.0, 8.0, 7.0, and 6.0 mm, respectively. The median volume of LNs at pre-ablation and 3, 6, 9, 12, 18, 24, and 36 months post-ablation were 251.2 mm³ and 206.7, 167.2, 166.2, 155.7, 153.9, 153.9, and 113.1 mm³, respectively. The largest diameter and the volume of the cervical metastatic LNs at the last post-ablation was significantly smaller than the pre-ablation level (p = .0016; p = .0018). Serum Tg level at the last post-ablation (median 1.25 ng/mL) was significantly lower than the pre-ablation level (median 8.35 ng/mL) (p = .001). There were no complications.Conclusion: MWA is a safe and effective novel treatment option for cervical metastatic LN that emerge post resection of PTC.

Ultrasound-guided radiofrequency ablation for papillary thyroid microcarcinoma: a retrospective analysis of 198 patients

Purpose: To evaluate the safety and efficacy of ultrasound-guided RFA for the treatment of papillary thyroid microcarcinoma (PTMC).Materials and methods: The data of 204 nodules from 198 PTMC patients who were treated using RFA were retrospectively reviewed in this study. Demographic variables, complication details and CEUS results in different time points were collected. The volumes and volume reduction rate (VRR) of the ablated area under CEUS at different follow-up time points were calculated and compared.Results: All the patients were successfully treated without major complication. Mild complications included cervical discomfort in three cases, postoperative cervical pain in one case, and transient hoarse voice in five cases. The volume of the ablated area in the 1st, 3rd, 6th, 12th, 18th and 24th month postoperatively were 241.7 ± 298.3mm³, 89.8 ± 147.2 mm³, 37.6 ± 87.2 mm³, 13.6 ± 59.8 mm³, 2.4 ± 14.4 mm³, and 0.2 ± 2.0 mm³ respectively, with a statistically significant decrease (F = 138.1, p = .000), and the VRR in those time points were 73.9 ± 13.7%, 90.5 ± 8.2%, 96.1 ± 5.9%, 98.8 ± 3.2%, 99.6 ± 1.9% and 99.8 ± 1.0% respectively, with a statistically significant decrease (F = 695.3, p = .000).Conclusions: US-guided RFA is safe and effective for PTMC, with a good oncological outcome and VRR. Further randomized controlled prospective trials are still needed to compare the value of RFA and surgery.

The Clinical Application of Core-Needle Biopsy after Radiofrequency Ablation for Low-risk Papillary Thyroid Microcarcinoma: A Large Cohort of 202 Patients Study

Purpose: To evaluate the clinical application of core-needle biopsy (CNB) for low-risk papillary thyroid microcarcinoma (PTMC) after radiofrequency ablation (RFA) Methods: A total of 202 patients with 211 low-risk PTMCs were included in this study. RFA procedure was used the hydrodissection technique and moving-shot technique. Patients were followed at 1, 3, 6, 12 months and every 6 months thereafter. The volume of ablation area and the volume reduction ratio (VRR) were calculated. At 3 or 6 months after RFA, CNB was performed to the central zone, the peripheral zone and surrounding thyroid parenchyma for post-ablation evaluation. Results: The mean volume of tumors was 102.34±93.84 mm³ (range 4.19-424.10 mm³), which decreased significantly to 1.37±7.74 mm³ (range 0-73.30 mm³) at a mean follow-up time of 24.42±9.15 months (range 3-42 months) with a mean VRR of 99.14±4.18% (range 71.88-100%). A total of 3 ablation areas had positive CNB in the peripheral zone and underwent additional RFA. No recurrent or suspicious metastatic lymph nodes were detected Conclusion: CNB is a feasible and effective evaluation for low-risk PTMC after RFA, which can detect residual cancer cells early.

Ultrasound-Guided Radiofrequency Ablation Versus Surgery for Low-Risk Papillary Thyroid Microcarcinoma: Results of Over 5 Years' Follow-Up

Background: Papillary thyroid microcarcinoma (PTMC) typically carries an excellent prognosis regardless of the treatment option pursued. Radiofrequency ablation (RFA) for thyroid disease has been utilized for benign lesions and in patients who are poor surgical candidates for thyroid cancers with compression symptoms, but the efficacy and limitations of RFA as first-line therapy for PTMC has not been described in adequate detail. The purpose of our study was to investigate RFA versus thyroidectomy in terms of efficacy, oncologic outcomes, quality of life, complications, and costs over a 5-year period of follow-up. Methods: From January 2013 to November 2013, 174 consecutive patients with an isolated, solitary intrathyroidal PTMC were identified in a Chinese teaching hospital. Those with more aggressive or advanced PTMCs were not included. Ninety-four patients elected RFA and 80 patients elected surgery for treatment of these PTMC. Nodules were confirmed to be PTMC without an aggressive histological type by core needle biopsy in the RFA group and by final surgical pathology in the surgery group. The extent of surgery was decided based on patient preferences in consultation with the surgeons. Of all the patients, 58 (72.5%) underwent lobectomy, 22 (27.5%) underwent total thyroidectomy, and 53 (66.3%) underwent lymph node dissection. Pre- and post-treatment variables were compared between the two groups, including demographics, tumor characteristics, treatment, local tumor progression, lymph node metastasis, distant metastasis, local recurrence, complications, and quality-of-life findings. Results: Patient-specific variables were similar between groups, as were oncologic outcomes after 5 years of follow-up. When compared with RFA, surgery took longer, had a longer hospitalization time, and was costlier (all p < 0.001). The surgery group had three complications, with 2 (2.5%) permanent recurrent laryngeal nerve injuries and 1 (1.3%) case of permanent hypoparathyroidism, while none was reported in the RFA group (p = 0.095). The surgery group had a lower post-treatment thyroid-related quality of life. Conclusions: For carefully selected low-risk intrathyroidal PTMC, RFA was not oncologically inferior to open surgery, and it was associated with a higher quality of life and lower overall costs.

Preliminary report of microwave ablation for the primary papillary thyroid microcarcinoma: a large-cohort of 185 patients feasibility study

PURPOSE

To assess the safety and efficacy of microwave ablation (MWA) for primary papillary thyroid microcarcinoma (PTMC) with a large sample of 185 patients.

METHODS

A total of 185 patients underwent MWA for 206 primary PTMC nodules. They received ultrasound follow-up at 1, 3, 6, and 12 months after MWA and every 6 months thereafter. Nodule volumes were calculated at each follow-up and compared with those before MWA. Additionally, the volume reduction rate (VRR) of the nodules was calculated. Patients' thyroid functions were tested before and 1 month after MWA.

RESULTS

The mean follow-up time of the 185 patients was 20.7 ± 8.8 months (range 12-36 months). During the follow-up period, the mean volume of the 206 nodules was 100.1 ± 92.9 mm³ (range 3.6-423.9) before MWA, which decreased to 2.2 ± 5.6 mm³ (range 0-20.3 mm³) after MWA (P = 0.000). The mean VRR of the nodules was 98.65 ± 3.60% after MWA (range 83.85-100%). One hundred and seventy four of 206 nodules (84.5%) were fully absorbed. Compared with the preoperative results, no significant variation in thyroid function was observed 1 month after MWA. Thirty-eight patients (20.5%) had different types of complications, ranging from minor to major. Five patients (2.7%) had hoarseness, 11 patients (5.9%) had bleeding, 21 patients (11.4%) had earache or toothache, and one patient had another lesion 1 month after MWA.

CONCLUSIONS

This preliminary study suggests that MWA is safe and effective in the treatment of primary PTMC and offers a new alternative for clinical treatment.

Ultrasound-guided percutaneous laser ablation for papillary thyroid microcarcinoma: a retrospective analysis of 37 patients

BACKGROUND

Over the past ten years, more papillary thyroid microcarcinoma (PTMC) has been diagnosed more frequently due to the development of imaging technology, and the incidence of PTMC has increased significantly. Ultrasound-guided percutaneous laser ablation (PLA) is mainly used for benign thyroid nodules, and few studies have been published on the use of PLA for PTMC. In the present study, a retrospective analysis was performed to explore the efficacy of PLA for PTMC.

METHODS

A total of 37 patients with PTMC who underwent PLA were included in this study. Measurement of the lesion volume and serum thyroid hormone levels and clinical evaluation were performed at 1, 3, 6, and 12 months and every 6 months thereafter.

RESULTS

We found that all patients were successfully treated with PLA without serious complications. At the last follow-up visit, 12/37 (32.4%) primary lesions had disappeared, and 24/37 (64.9%) remained as cicatricial hyperplasia. One patient (2.7%) had cervical lymph node metastasis at 24 months post-operatively and underwent open surgery.

CONCLUSION

Our initial studies suggest that ultrasound-guided PLA is a safe and effective treatment for PTMC.

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.

Percutaneous ultrasound-guided laser ablation for the treatment of cervical tuberculous lymphadenitis: a pilot study

OBJECTIVE

This study was performed to assess the feasibility, effectiveness, and safety of percutaneous ultrasound (US)-guided laser ablation (LA) for the treatment of cervical tuberculous lymphadenitis (CTBL).

METHODS

We retrospectively reviewed 11 patients with CTBL (mean age, 32.0 ± 8.6 years; range, 18-47 years) who underwent percutaneous US-guided LA from June 2014 to December 2016 with a subsequent 12-month follow-up. We assessed the mean volume reduction and contrast-enhanced US (CEUS) changes of the target lymph nodes as well as the tolerability and adverse effects of LA.

RESULTS

The mean ablation energy was 522 ± 312 J (range, 204-1317 J). All 17 enrolled target lymph nodes were completely non-enhanced after LA treatment as detected by CEUS, indicating complete ablation of all lymph nodes (100%). The target lymph nodes significantly decreased in volume by a mean of 74.0% ± 15.6% from baseline to 12 months after LA. The LA procedure was well tolerated, and none of the 11 patients developed severe complications during the 12-month follow-up.

CONCLUSION

Percutaneous US-guided LA for the treatment of CTBL exhibits good tolerability, minimal invasiveness, and few adverse effects. Further investigations with larger sample sizes and longer follow-up periods are warranted to confirm these findings.

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.

Percutaneous Laser Ablation of Unifocal Papillary Thyroid Microcarcinoma: Utility of Conventional Ultrasound and Contrast-Enhanced Ultrasound in Assessing Local Therapeutic Response

PURPOSE

To investigate the use of conventional ultrasound and contrast-enhanced ultrasound (CEUS) in assessing local therapeutic response of percutaneous laser ablation (PLA) for papillary thyroid microcarcinoma (PTMC).

METHODS

Sixty-four patients with 64 PTMCs who were referred to our hospital from November 2013 to July 2016 were treated with PLA. The extent of ablation was assessed by CEUS at 10-20 min and 7 days after PLA. The size and volume of the ablation zone were evaluated on conventional ultrasound at 1 h, 1, 3, 6 and 12 months, and every half-year thereafter, and recurrences were also recorded. Ultrasound-guided fine needle aspiration biopsy (FNAB) of the ablated area was performed at 1, 6 and 12 months after PLA.

RESULTS

Two incomplete ablations were detected by CEUS, and a second ablation was performed. The mean largest diameter and volume of the ablated area on CEUS at 10-20 min and 7 days after PLA were significantly larger than those of pre-treatment on conventional ultrasound (p < 0.05, for both). At the last follow-up, the mean largest diameter was reduced from 4.6 ± 1.5 to 0.6 ± 1.3 mm (p < 0.0.5), and the average volume was 41.0 ± 40.4 mm³, which decreased to 1.8 ± 6.7 mm³ (p < 0.0.5). A cervical metastatic lymph node was detected on ultrasound and confirmed by ultrasound-guided FNAB at 30 months after PLA.

CONCLUSIONS

CEUS could play a crucial role in assessing the completeness of PLA for treating PTMC, and conventional ultrasound can not only guide the FNAB process but also is important in the follow-up of PTMC after PLA.