Microwave ablation vs. surgery for papillary thyroid carcinoma with minimal sonographic extrathyroid extension: a multicentre prospective study

Analysis and prediction of ablation zone absorption in papillary thyroid microcarcinoma undergoing microwave ablation

PURPOSE

This study aims to investigate the factors that influence the absorption of the ablation zone in patients with papillary thyroid microcarcinoma (PTMC) following microwave ablation (MWA) and construct a nomogram for predicting the absorption of the ablation zone.

METHODS

Data from 150 patients with 187 PTMCs who received MWA between April 2020 and April 2023 were analyzed. PTMCs were randomly divided into training and validation sets in a 7:3 ratio. Univariable and multivariable analyses of Cox regression were utilized to identify the independent variables associated with the absorption of the ablation zone in PTMC post-MWA, and a nomogram was established. The discrimination and calibration performance of the nomogram was assessed using the time-dependent receiver operating characteristic curves and calibration curves.

RESULTS

At 12 months post-MWA, a 53% proportion of complete disappearance of the ablation zone was observed. Energy delivered per milliliter of volume measured in contrast-enhanced ultrasound (CEUS) mode immediately post-MWA (Edv) and the CEUS margin at 1-month post-WMA were identified as independently correlated with the ablation zone absorption post-MWA (P = 0.001, P < 0.001 respectively). A nomogram incorporating these two factors was constructed. The areas under the receiver operating characteristic curve were all above 0.78 in the training and validation sets.

CONCLUSION

Edv and the CEUS margin at 1-month post-MWA were found to be significantly associated with complete absorption of the ablation zone in PTMC patients following MWA. The established nomogram can assist practitioners in formulating more appropriate ablation strategies and provide a clinical basis for explaining the recovery status to patients.

Management of low-risk papillary thyroid cancer. Minimally-invasive treatments dictate a further paradigm shift?

BACKGROUND

Current management options for PTMC include lobo-isthmectomy and active surveillance (AS). Recently, ultrasound-guided minimally invasive procedures (MITs) are offered as a nonsurgical therapy for PTMC because they do not require hospitalization and general anaesthesia, and do not result in loss of thyroid function or cosmetic damage. MITs are reported to consistently provide, mostly in large retrospective series of patients, a rapid, safe, and cost-effective way to eradicate low-risk thyroid malignancies. However, conclusive data from well-conducted prospective studies on the histologically-proven completeness of tumor ablation and the long-term clinical advantages versus AS are still lacking.

OBJECTIVES

This study aimed to evaluate the efficacy and safety of ultrasound-guided minimally invasive treatments (MITs) for PTMC in comparison to traditional surgical methods and active surveillance, and to assess their role in current clinical practice.

METHODS

A structured literature review was conducted using keywords related to PTMC, MIT, and comparative techniques. Studies were evaluated based on treatment modality, patient selection, follow-up duration, complication rates, and clinical outcomes.

RESULTS

MITs have shown promising results in the management of PTMC. These treatments offer several advantages over surgery, such as reduced use of surgical resources, lower costs, minimal work disruption, and fewer major complications. However, there are still limitations, including the need for long-term surveillance and the potential risk of incomplete tumor ablation.

CONCLUSIONS

MITs represent a promising non-surgical option for managing low-risk PTMC, especially for patients ineligible for or refusing surgery. Despite favorable outcomes, more robust prospective data are needed to confirm their long-term benefits and completeness of tumor ablation. Interdisciplinary discussions and thorough patient education on the advantages and limitations of MITs are crucial for informed decision-making.

Comparison between thermal ablation and surgery in low risk papillary thyroid carcinoma: a prospective study

Objective

To conduct a comparative analysis of the efficacy, safety, and impact on quality of life outcomes between thermal ablation and surgical interventions in patients diagnosed with papillary thyroid carcinoma (PTC).

Methods

A prospective study was undertaken, enrolling patients with PTC ≤5mm who underwent radiofrequency ablation (RFA), laser ablation (LA), or surgery, for analysis of efficacy and safety outcomes. The Thyroid Cancer-Specific Quality of Life questionnaire was administered to all patients before treatment and at 3, 6, and 12 months post-treatment.

Results

A total of 162 eligible patients were included in the study. Major complications were not observed in the RFA and LA groups, while five cases were reported in the surgery group, although no statistically significant differences were observed. Minor complications were documented in two, three, and 14 patients in the RFA, LA, and surgery groups, respectively, with no significant variances noted. Surgical duration and hospitalization time were notably shorter in the thermal ablation groups. At the final follow-up, complete disappearance of nodules was seen in 71.4% of cases treated with RFA and 71.0% of cases managed with LA, with no significant disparities between the groups. Both RFA and LA exhibited similar effects on quality of life, with thermal ablation techniques showing better functional outcomes in comparison to surgery. Across all groups, adverse effects were most pronounced at the 3-month post-treatment mark but gradually reverted to baseline levels in the thermal ablation group, contrasting with the surgery group.

Conclusions

For PTC ≤5mm, both RFA and LA exhibited similar cancer control outcomes and superior quality of life on par with surgery, while minimizing complications. These findings underscore the promise of RFA and LA as potential standard treatments for small PTCs, subject to further confirmation in future studies.

Radiofrequency ablation for capsular-located versus noncapsular-located papillary thyroid microcarcinoma: a propensity score matching study of 1095 patients

OBJECTIVES

To assess the safety and efficacy of radiofrequency ablation (RFA) for capsular-located papillary thyroid microcarcinoma (PTMC) in a large cohort and to compare its outcomes with those of noncapsular-located PTMC.

METHODS

We retrospectively reviewed patients who underwent RFA for solitary capsular-located and noncapsular-located low-risk PTMC (n = 1095) from June 2014 to October 2020. To balance confounding variables between capsular and noncapsular groups, we employed the 1:1 propensity score matching approach. We evaluated and compared tumor changes, disease progression, and complications in both groups. Furthermore, we analyzed the association between capsular location and disease progression using multivariable Cox regression.

RESULTS

During a mean follow-up time of 29.86 ± 16.14 months and 29.73 ± 15.69 months, no substantial difference was observed between capsular and noncapsular groups in the latest volume (0.83 ± 3.66 mm3 vs. 0.85 ± 3.67 mm3, p = 0.44) and volume reduction ratio (99.29 ± 4.04% vs. 99.43 ± 3.03%, p = 0.43), and cumulative disappearance rate (87.87% vs. 86.07%, p = 0.31). In addition, no significant differences were observed in complication incidence (1.35% vs. 1.12%, p = 0.76) and progression-free survival (p = 0.53). Based on adjusted multivariate Cox proportional hazard analysis, the association between capsular location and disease progression was nonsignificant (all p > 0.05).

CONCLUSION

This study demonstrates that the short-term outcomes of RFA for capsular-located PTMCs are comparable to those of noncapsular-located PTMCs. These findings indicate that RFA may be a viable and effective alternative for eligible patients with solitary capsular-located PTMC.

CLINICAL RELEVANCE STATEMENT

Radiofrequency ablation may serve as a safe and effective alternative treatment method for eligible patients with capsular-located and noncapsular-located papillary thyroid microcarcinoma.

KEY POINTS

• The safety and efficacy of radiofrequency ablation for capsular-located and noncapsular-located papillary thyroid microcarcinomas were comparable. • Disease progression did not differ significantly between capsular-located and noncapsular-located papillary thyroid microcarcinomas. • The incidence of complications for capsular-located papillary thyroid microcarcinoma was low.

Radiofrequency ablation for papillary thyroid microcarcinoma with a trachea-adjacent versus trachea-distant location

OBJECTIVE

To evaluate the outcomes of radiofrequency ablation (RFA) for papillary thyroid microcarcinoma (PTMC) adjacent to the trachea and compare them with those of PTMC distant from the trachea.

METHODS

Patients who received RFA for solitary low-risk PTMC between June 2014 and July 2020 were reviewed and classified into adjacent and distant groups. To balance between-group confounders, the propensity score matching approach was employed. Volume, volume reduction ratio (VRR), tumor disappearance, complications, and disease progression were assessed and compared between the groups. Furthermore, factors affecting disease progression were evaluated.

RESULTS

A total of 122 and 470 patients were included in the adjacent and distant groups, respectively. Overall VRR was 99.5% ± 3.1 and cumulative tumor disappearance rate was 99.4% after a mean follow-up time of 40.1 months ± 16.2. Overall disease progression and complications incidence were 3.7% and 1.0%, respectively. No substantial differences were observed between the two groups in the latest volume (0.8 mm3 ± 4.1 vs. 0.9 mm3 ± 4.2, p = .77), VRR (99.7% ± 1.6 vs. 99.5% ± 2.7, p = .75), cumulative tumor disappearance rate (92.6% vs. 94.2%, p = .58), and incidence of disease progression (4.1% vs. 4.5%, p = .70) and complication (1.7% vs. 0.8%, p = .86) after 1:2 matching. Additionally, tracheal adjacency exhibited no association with disease progression in multivariate Cox regression analysis (p = .73).

CONCLUSION

For eligible patients with PTMC located adjacent to or distant from the trachea, RFA may offer a safe and effective alternative treatment method.

Microwave ablation versus liver resection for primary intrahepatic cholangiocarcinoma within Milan criteria: a long-term multicenter cohort study

Background

Ablation has been recommended by worldwide guidelines as first-line treatment for hepatocellular carcinoma (HCC), while evidence regarding its efficacy for primary intrahepatic cholangiocarcinoma (iCCA) is lacking. We aimed to study the efficacy of ablation in treating iCCA by comparing its prognosis with surgery.

Methods

In this real-world multicenter cohort study from January 2009 to June 2022, 10,441 iCCA patients from ten tertiary hospitals were identified. Patients who underwent curative-intent microwave ablation (MWA) or liver resection (LR) for tumors within Milan criteria were included. One-to-many propensity score matching (PSM) at variable ratios (1:n ≤4) was used to balance baseline characteristics. Mediation analysis was applied to identify potential mediators of the survival difference.

Findings

944 patients were finally enrolled in this study, with 221 undergoing MWA and 723 undergoing LR. After PSM, 203 patients in the MWA group were matched with 588 patients in the LR group. The median follow-up time was 4.7 years. Compared with LR, MWA demonstrated similar overall survival (5-year 44.8% versus 40.4%; HR 0.96, 95% CI 0.71-1.29, P = .761). There was an improvement in the 5-year disease-free survival rate for MWA from 17.1% during the period of 2009-2016 to 37.3% during 2017-2022, becoming comparable to the 40.8% of LR (P = .129). The proportion of ablative margins ≥5 mm increased from 25% to 61% over the two periods, while this proportion of surgical margins was 62% and 77%, respectively. 34.5% of DFS disparity can be explained by the mediation effect of margins (P < .0001). Similar DFS was observed when both ablative and surgical margins exceeded 5 mm (HR 0.83, 95% CI 0.52-1.32, P = .41).

Interpretation

MWA may be considered as a viable alternative to LR for iCCA within Milan criteria when an adequate margin can be obtained.

Funding

National Natural Science Foundation of China.

Trajectory analysis of microwave ablation treatment effect on the quality of life and emotional distress in patients with papillary thyroid cancer

PURPOSE

Trajectory changes of quality of life (QOL) and psychological status in patients with T1N0M0 papillary thyroid cancer (PTC) after microwave ablation (MWA) treatment.

METHODS

Patients with T1N0M0 PTC who underwent MWA from March to August 2021 were included in this study. Patients completed the European Organisation for Research and Treatment of Cancer questionnaire (QLQ-C30), Thyroid Cancer-Specific Quality of Life Questionnaire (THYCA-QOL) and Hospital Anxiety and Depression Scale (HADS) at baseline, 3 months, 6 months, 9 months and 12 months after MWA.

RESULTS

181 patients were enrolled in this study. All patients met a minimum of 12 months of follow-up. The QOL at baseline and 12 months after MWA were 14.95 ± 1.78 and 14.19 ± 1.73 (P < 0.01), respectively. Patients' anxiety was 3.33 ± 1.81 and 1.49 ± 2.14 (P < 0.01), respectively. Patients' depression was 2.14 ± 2.10 and 1.40 ± 2.22 (P < 0.01), respectively. In the trajectory analysis, 73%, 19% and 8% of patients achieved significant improvement, slight improvement and stable in QOL, respectively, with older, female, lower education and lower monthly income as the risk factors of QOL. 63%, 31% and 6% of patients achieved significant improvement, slight improvement and stable in anxiety, respectively, with younger, female, lower education, lower monthly income, unmarried or divorced and higher T3, T4 levels as the risk factors of anxiety. 72%, 21% and 7% of patients achieved significant improvement, slight improvement and stable in depression, respectively, with younger, lower monthly income and unmarried or divorced as the risk factors of depression.

CONCLUSIONS

MWA can effectively improve the QOL and emotional distress of patients with T1N0M0 PTC.

Radiofrequency ablation for papillary thyroid cancer located in isthmus: comparison with that originated in thyroid lobe

PURPOSE

To analyze the outcomes of radiofrequency ablation (RFA) for isthmus papillary thyroid cancer (PTC) versus PTC originating from the lobes.

METHODS

Patients with solitary low-risk PTC treated with RFA between July 2014 and December 2019 were retrospectively reviewed. This study was approved by our institutional review board. Of the 562 patients, 104 and 458 had PTCs located in the thyroid isthmus and thyroid lobes, respectively. Local tumor progression (LTP), LTP-free survival (LTPFS), changes in tumor volume, and complications were compared between the two groups using propensity-score matching (PSM).

RESULTS

The isthmic and lobar groups showed no significant differences in LTP (2.9% vs. 3.8%), new PTC (2.9% vs. 2.9%), persistent lesions (0.0% vs. 0.2%), or LTPFS after PSM. Before PSM, the two groups showed significant differences in the volume reduction ratio (VRR) of the ablated tumors at 1, 3, 24, 30, and 48 months after RFA, but no differences between the two groups were observed in tumor volume, VRR, or disappearance rate after PSM (p > .05). One patient in the isthmic group presented with coughing, while another complained of hoarseness. Complications did not differ significantly between the two groups (p > .05).

CONCLUSIONS

The outcomes of RFA for patients with low-risk PTC in the thyroid isthmus and thyroid lobes were similar. Therefore, RFA may serve as an alternative treatment option for patients with low-risk isthmic PTC.

Radiofrequency Ablation of Unifocal Papillary Thyroid Microcarcinoma With BRAF V600E Mutation

CONTEXT

To date there is no study on the feasibility of radiofrequency ablation (RFA) for papillary thyroid microcarcinomas (PTMCs) with BRAF V600E mutation.

OBJECTIVE

This study was designed to evaluate the efficiency, safety, and prognosis of ultrasound (US)-guided percutaneous RFA for unifocal PTMCs with BRAF V600E mutation.

MATERIALS AND METHODS

Sixty patients with 60 unifocal BRAF V600E mutation-positive PTMCs who received US-guided RFA between January 2020 and December 2021 were retrospectively analyzed. The mean maximum PTMC tumor diameter was 5.8 ± 1.7 mm (range, 2.5-10.0 mm). All PTMCs were pathologically confirmed by fine needle aspiration or core needle biopsy, and BRAF V600E mutation was confirmed to be positive by real-time fluorescent quantitative polymerase chain reaction. Contrast-enhanced ultrasound (CEUS) was performed immediately after RFA to evaluate whether PTMCs were extendedly ablated. Ultrasound was performed 1, 3, 6, and 12 months after RFA and every 6 months thereafter to evaluate the changes in the ablation zone, local recurrence, and cervical lymph node metastasis (LNM). The complications were recorded and evaluated.

RESULTS

Extended ablation was achieved in all enrolled patients. The ablation zone sizes increased immediately after RFA compared with those of tumors before treatment. One month later, the ablation zone sizes were smaller than immediately after RFA. At the last follow-up assessment, 42 nodules (70.0%) completely disappeared and the ablation zones of 18 nodules (30.0%) showed fissure-like changes. No local recurrence or cervical LNM was detected. Voice change (1.7%) was the only major complication.

CONCLUSION

RFA is effective and safe in treating unifocal PTMCs with BRAF V600E mutation, especially when surgery is not feasible or refused by patients who are unwilling to continue active surveillance.

Clinical outcomes of radiofrequency ablation for solitary T1aN0M0 versus T1bN0M0 papillary thyroid carcinoma: a propensity-matched cohort study

OBJECTIVE

To conduct a cohort study comparing the treatment outcomes of radiofrequency ablation (RFA) therapy for solitary T1aN0M0 (T1a) versus T1bN0M0 (T1b) papillary thyroid carcinoma (PTC).

METHODS

This retrospective analysis comprised 310 patients with low-risk PTC undergoing RFA classified into T1a (n = 272) and T1b (n = 38) groups according to the tumor size. A comparative analysis between the two groups was conducted for the volume reduction ratio (VRR), volume, local tumor progression (LTP), and recurrence-free survival (RFS) before and after 1:2 propensity score matching (PSM). Cox analysis was conducted to examine the influence of several variables, including T1b, on recurrence following RFA for PTC.

RESULTS

The total VRR was 99.99 ± 0.11% throughout the median follow-up duration of 26 months, and the overall incidence of LTP was 2.58% (8/310). No irrecoverable complications occurred after RFA. The variations between the T1a and T1b groups following PSM were insignificant in terms of volume (p = 0.574), VRR (p = 0.574), complete disappearance rate (p = 0.210), LTP incidence (p = 1.000), and RFS rate (p = 0.610). The correlation between T1b and LTP continued to be insignificant (p = 0.686). No distant metastasis or delayed surgery occurred.

CONCLUSIONS

The presence of T1b did not influence the patients' prognoses following RFA for T1N0M0 PTC. After appropriate patient selection and adequate preoperative assessment, RFA has the potential to serve as an effective therapy for individuals with T1a and T1b PTC.

Effectiveness and Safety of Percutaneous Treatment in Lesions Suggestive of Thyroid Cancer (Bethesda V and VI-T1aN0M0) Compared to Surgical Treatment: Systematic Review and Meta-Analysis

INTRODUCTION

Thyroid nodules are common entities, with 5% malignancy. Differentiated thyroid cancer represents 90% of thyroid malignancies, with papillary carcinoma being the most common. Management is generally surgical; among its complications are injury to the recurrent laryngeal and superior laryngeal nerve, causing hoarseness, postsurgical hypoparathyroidism, hypothyroidism, and pain. Other noninvasive percutaneous interventions of thermal ablation such as microwave, radiofrequency, or laser incur lower costs and could be an option for treatment.

OBJECTIVE

To determine the effectiveness and safety of thermal ablation in lesions suspected of thyroid cancer (Bethesda V and VI/T1aN0M0) compared to surgical treatment.

METHODS

Systematic review/meta-analysis of observational studies and clinical trials. Database search includes MEDLINE/PUBMED, Embase, Scopus, Scielo, and BVS/LILACS. Studies on patients over 18 years of age with lesions suspicious of thyroid cancer were included.

RESULTS

A total of 10 studies were obtained, with 2939 patients: 1468 subjected to thermal ablation and 1471 to surgery. Regarding effectiveness, no differences were found in local recurrence [relative risk (RR) 1.17 (95% CI 0.69-1.99)] and cervical lymph node metastasis [RR 0.76 (95% CI 0.43-1.36)]. Regarding safety, infection [RR 0.29 (95% CI 0.05-1.74)], hematoma [RR 0.57 (95% CI 0.17-1.94)], and transient hoarseness [RR 0.77 (95% CI 0.39-1.51)] were evaluated, without difference. However, permanent hoarseness had significant differences in favor of thermal ablation [RR 0.29 (95% CI 0.11-0.75)].

CONCLUSIONS

Thermal ablation for the treatment of T1aN0M0 papillary thyroid carcinoma is equally effective when compared to surgical techniques and offers a better safety profile, particularly in permanent hoarseness.

Microwave ablation of solitary T1N0M0 papillary thyroid carcinoma: A case report

BACKGROUND

The gold standard treatment for papillary thyroid carcinoma is total thyroidectomy and indications for microwave thermal ablation for primary thyroid cancers have not yet been clearly established However, some patients refuse surgery and others have no indication for it, for example patients under palliative care as in this case, or cannot undergo surgery, based on their comorbidities. These indications are described in the most recent Korean, North American and European guidelines. Laser ablation, radiofrequency ablation, and microwave ablation are similarly safe and effective, so the choice should be based on the specific competences and resources of the pertaining centers. These indications are Percutaneous minimally-invasive techniques; they can be useful to stop disease progression and as an alternative to surgery in patients with contraindication or who refuse surgery. We present a case of a thyroid papillary carcinoma with 17 mm effectively treated with microwave thermal ablation and without recurrence after one year of follow up.

CASE SUMMARY

The authors present a case of a 71-years-old patient with a left lobe papillary thyroid carcinoma with 13 mm × 17 mm × 13 mm, with no indication for thyroid surgery given the context of another cancer in palliative treatment. Microwave thermoablation was performed on December 2021. Four months later he repeated computed tomography (CT) scan, which showed that the tumor had disappeared. Six months after ablation he underwent a positron emission tomography/CT-fluorodeoxyglucose scan, which didn't show any evidence of hypermetabolic tumor lesions.

CONCLUSION

This case shows microwave thermoablation can be a safe and effective alternative to surgery in patients with no conditions to undergo surgery or when they refuse it. By treating the tumor, with this minimally invasive technique, we are stopping its growth and avoiding disease progression.

Microwave ablation of solitary T1N0M0 papillary thyroid carcinoma: A case report

BACKGROUND

The gold standard treatment for papillary thyroid carcinoma is total thyroidectomy and indications for microwave thermal ablation for primary thyroid cancers have not yet been clearly established However, some patients refuse surgery and others have no indication for it, for example patients under palliative care as in this case, or cannot undergo surgery, based on their comorbidities. These indications are described in the most recent Korean, North American and European guidelines. Laser ablation, radiofrequency ablation, and microwave ablation are similarly safe and effective, so the choice should be based on the specific competences and resources of the pertaining centers. These indications are Percutaneous minimally-invasive techniques; they can be useful to stop disease progression and as an alternative to surgery in patients with contraindication or who refuse surgery. We present a case of a thyroid papillary carcinoma with 17 mm effectively treated with microwave thermal ablation and without recurrence after one year of follow up.

CASE SUMMARY

The authors present a case of a 71-years-old patient with a left lobe papillary thyroid carcinoma with 13 mm × 17 mm × 13 mm, with no indication for thyroid surgery given the context of another cancer in palliative treatment. Microwave thermoablation was performed on December 2021. Four months later he repeated computed tomography (CT) scan, which showed that the tumor had disappeared. Six months after ablation he underwent a positron emission tomography/CT-fluorodeoxyglucose scan, which didn’t show any evidence of hypermetabolic tumor lesions.

CONCLUSION

This case shows microwave thermoablation can be a safe and effective alternative to surgery in patients with no conditions to undergo surgery or when they refuse it. By treating the tumor, with this minimally invasive technique, we are stopping its growth and avoiding disease progression.

Microwave Ablation for Papillary Thyroid Microcarcinoma with and without US-detected Capsule Invasion: A Multicenter Prospective Cohort Study

Background Microwave ablation (MWA) has achieved favorable results in the treatment of papillary thyroid microcarcinoma (PTMC) confined in glandular parenchyma. However, studies on the outcome of MWA for PTMC with US-detected capsular invasion remain unclarified in the literature. Purpose To compare the feasibility, effectiveness, and safety of MWA in the treatment of PTMC with and without US-detected capsular invasion. Materials and Methods Participants from 12 hospitals with a PTMC maximal diameter of 1 cm or less without US- or CT-detected lymph node metastasis (LNM) who planned to undergo MWA were enrolled in this prospective study between December 2019 and April 2021. All tumors were evaluated with preoperative US and were divided into those with and those without capsular invasion. The participants were observed until July 1, 2022. The primary end points, including technical success and disease progression, and the secondary end points, including treatment parameters, complications, and tumor shrinkage during follow-up, were compared between the two groups, and multivariable regression was performed. Results After exclusion, 461 participants (mean age, 43 years ± 11 [SD]; 337 women) were included: 83 with and 378 without capsular invasion. After one participant with capsular invasion aborted MWA because of technical failure, 82 participants with and 378 participants without capsular invasion (mean tumor volume, 0.1 mL ± 0.1 vs 0.1 mL ± 0.1; P = .07) were analyzed with a mean follow-up period of 20 months ± 4 (range, 12-25 months) and 21 months ± 4 (range, 11-26 months), respectively. In those with and those without capsular invasion, comparable technical success rates were achieved (99% [82 of 83] vs 100% [378 of 378], P = .18), with one and 11 complications, respectively (1% [one of 82] vs 3% [11 of 378], P = .38). There was no evidence of differences in disease progression (2% [one of 82] vs 1% [four of 378]; P = .82) or tumor shrinkage (mean, 97% ± 8 [SD] vs 96% ± 13; P = .58). Conclusion Microwave ablation was feasible in the treatment of papillary thyroid microcarcinoma with US-detected capsular invasion and showed comparable short-term efficacy with or without the presence of capsular invasion. © RSNA, 2023 Clinical trial registration no. NCT04197960 Supplemental material is available for this article.

Latest evidence of microwave ablation for papillary thyroid microcarcinoma compared with surgery: A systematic review and meta-analysis

Background

The most typical thyroid gland malignant lesion is papillary thyroid cancer (PTC). In many nations, the prevalence of thyroid cancer (TC) is rising, particularly papillary thyroid microcarcinoma (PTMC). Microwave ablation (MWA) has been gradually carried out in some patients with benign thyroid nodules, some low-risk PTMC, and metastatic lymph nodes in the neck. The role and safety of MWA remain controversial topics. So we conducted this study to provide the latest evidence of MWA for PTMC compared with surgery.

Methods

Patients' postoperative outcomes (duration of hospital stay and hospitalization expenditures), intraoperative outcomes (surgery time, blood loss, and incision size), and follow-up outcomes were all examined (complication rate, recurrence rate, and lymph node metastasis). The effectiveness and safety of MWA versus surgery for PTMC patients were compared using the weighted mean difference (WMD) and odds ratio (OR).

Results

In total, we included 7 articles (7 trial comparisons) which contained 1, 567 PTMC patients. The results showed that MWA had significant advantages in operative time (WMD = -53.47, 95% CI: -67.62 to -39.32), postoperative hospital stay (WMD =-4.59, 95% CI: -6.40 to -2.77), hospitalization costs (WMD= -70.06, 95% CI: -90.93 to -49.19), blood loss (WMD =-28.07, 95% CI: -33.77 to -22.38), incisions size (WMD =-59.69, 95% CI: -67.79 to -51.59), and complication rates (OR = 0.28; 95% CI: 0.18 to 0.42) compared with surgery. It also showed that recurrence rates and risk of lymph node metastasis are similar to surgery.

Conclusions

For PTMC patients, MWA could be an efficient, safe, and affordable therapy.

Upgraded hydrodissection and its safety enhancement in microwave ablation of papillary thyroid cancer: a comparative study

OBJECTIVES

To study the efficacy and safety of an improved hydrodissection protocol based on the perithyroidal fascial space during microwave ablation for papillary thyroid carcinoma (PTC).

METHODS

The data of 341 patients (94 men and 247 women, median age 41 years old, 25%-75% interquartile range 34-53 years old, nodule maximum diameter 0.2-1.9 cm) who underwent microwave ablation for PTC were retrospectively reviewed. Among them, 185 patients underwent traditional hydrodissection and served as a control group, and 156 patients underwent improved hydrodissection based on perithyroidal fascial spaces, constituting the improved group. Improvements in safety were analyzed by comparing complications between the two groups. The characteristics of hydrodissected spaces, complications, and follow-up results were recorded.

RESULTS

Hydrodissection was successfully performed in all enrolled patients according to the protocol. The incidence of hoarseness caused by recurrent laryngeal nerve injury, the most common complication in thermal ablation of thyroid nodules, was significantly lower in the improved group than in the control group (1.9% vs. 8.1%, p = 0.021). The median hoarseness recovery time in the improved group was shorter than that in the control group (2 months vs. 3 months, p = 0.032). During follow-up, no local recurrence was encountered in either group. The tumor disappearance rate was not significantly different between the two groups (69.9% vs. 75.7%, p = 0.228).

CONCLUSIONS

Improved hydrodissection based on perithyroidal fascial spaces had better protective effects than traditional hydrodissection.