Minimally Invasive Treatments of Benign Thyroid Nodules: A Network Meta-Analysis of Short-Term Outcomes

Advancements in microwave ablation for tumor treatment and future directions

Microwave ablation (MWA) is a minimally invasive treatment that uses thermal energy to target and destroy tumors. Compared to other ablation methods, such as radiofrequency ablation (RFA), MWA operates at higher frequencies, allowing for faster ablation and larger treatment areas. In addition to its direct tumor-destroying effects, MWA has been shown to activate immune responses, contributing to long-term antitumor effects. MWA can also be combined with surgery, chemotherapy, and immunotherapy to enhance treatment outcomes. This review examines the current research on MWA's technical innovations, clinical applications, and its potential in improving cancer treatment efficacy.

Ultrasound-Guided Thermal Ablation Versus Thyroidectomy in the Treatment of Benign Thyroid Nodules: Systematic Review and Meta Analysis

Ultrasound-guided thermal ablation (TA) is a minimally invasive intervention for treating benign thyroid nodules (BTNs). This meta-analysis aims to systematically compare the safety and efficacy of ultrasound-guided TA with surgery in treating BTNs. Relevant studies were identified through searching electronic databases. Included studies focused on comparing TA for BTNs with surgical resection. Primary endpoints encompassed length of hospital stay, procedure time, symptom improvement, cosmetic score, and excellent cosmetic results. Other outcomes include all complications (hypothyroidism, hoarseness, hematoma, blood loss, wound infection, parathyroid injury, chocking, or cough), recurrence, postoperative pain, visual analog scale (VAS) score, scar length, thyroid hormone levels, and finally stress response outcomes. Twenty-six studies (7 randomized controlled trials and 19 cohort studies) were included. Our findings revealed that TA was associated with shorter hospital stays (MD = -3.30, 95% CI [-3.82, -2.79], P < .00001), reduced procedure time (MD = -47.75, 95% CI [-54.89, -40.61] P < .00001), superior cosmetic outcomes (RR = 1.11, 95% CI [1.00, 1.22], P = .04), lower postoperative pain levels, and lower VAS score. Additionally, surgical resection was linked to a higher incidence of hoarseness, hypothyroidism, parathyroid injury, and blood loss. However, no significant differences were observed in rates of wound infection, hematoma, or recurrence between the two treatment modalities. Our meta-analysis suggests that ultrasound-guided TA represents a viable alternative to surgery for treating BTNs, especially for patients unwilling or unable to undergo surgical intervention. This technique was found to be safe and effective. However, future evidence is mandatory to establish TA to a specific type of nodule, to preserve patients from second interventions.

Comparison of efficacy and safety of different minimally invasive therapies for thyroid nodules: A network meta-analysis

OBJECTIVE

This study aimed to compare efficacy and safety of minimally invasive therapies such as radiofrequency ablation (RFA), microwave ablation (MWA), ethanol ablation (EA), and laser ablation (LA) for thyroid nodules through network meta-analysis (NMA).

METHODS

This study searched PubMed, Web of Science, Embase, and The Cochrane Library databases to collect randomized controlled trials (RCTs) or cohort studies comparing efficacy and safety of different minimally invasive therapies for thyroid nodules. Newcastle-Ottawa Scale (NOS) was implemented to assess quality of included cohort studies, and Cochrane risk of bias assessment tool was utilized to evaluate quality of included RCTs. Eligible studies contained at least one of the following clinical outcome measures: volume reduction rate (VRR), symptom score, cosmetic score, nodule regrowth rate, and complication rate. STATA software was utilized for NMA.

RESULTS

Sixteen eligible studies (4 RCTs, 11 retrospective cohort studies, 1 prospective cohort study) involved 4094 patients. NMA results revealed that RFA group had the highest VRR at 1 months and 12 months. There were no significant differences in symptom scores and cosmetic scores among all treatment methods, with the lowest symptom scores and cosmetic scores in RFA group. LA group had a significantly higher nodule regrowth rate than RFA and MWA groups, with the lowest in RFA group. There were no significant differences in complication rate among all treatment methods.

CONCLUSION

RFA had the highest VRR for thyroid nodules, and it excelled in symptom scores, cosmetic scores, and nodule regrowth rates.

Comparison of ultrasound-guided microwave ablation, laser ablation, and radiofrequency ablation for the treatment of elderly patients with benign thyroid nodules: A meta-analysis

BACKGROUND

A new minimally invasive technique, ultrasound-guided thermal ablation has become one of the treatment methods for benign thyroid nodules. This study aims to evaluate the efficacy and safety of laser ablation (LA), radiofrequency ablation (RFA), and microwave ablation (MWA) in the treatment of elderly patients with benign thyroid nodules.

METHODS

PubMed, Web of Science, and Cochrane Library were searched for qualified randomized controlled studies (RCTs) issued from establishing databases to March 2022. After screening and evaluating the article quality, the data on nodular volume reduction rate (VRR) and the incidence of complications after thermal ablation were extracted and analyzed by RevMan 5.3 and Stata l4.0.

RESULTS

The meta-analysis included seven articles with 3055 participants. We found that LA, RFA, and MWA could markedly reduce the volume of benign thyroid nodules. LA was superior to RFA and MWA in reducing the volume of benign thyroid nodules in 6 months of follow-up (all P < 0.05). LA, RFA, and MWA can be safely implemented in patients with benign thyroid nodules. The incidence of significant complications after the RFA group was enhanced compared with that in the MWA (P < 0.05), and the incidence of secondary complications after RFA was slightly higher than that of LA (P < 0.05).

CONCLUSION

LA, RFA, and MWA can markedly reduce the volume of benign thyroid nodules in elderly patients and can safely treat benign thyroid nodules.

Preoperative single-dose camrelizumab and/or microwave ablation in women with early-stage breast cancer: A window-of-opportunity trial

BACKGROUND

Immune checkpoint blockade has shown low response rates for advanced breast cancer, and combination strategies are needed. Microwave ablation (MWA) may be a trigger of antitumor immunity. This window-of-opportunity trial (ClinicalTrials.gov: NCT04805736) was conducted to determine the safety and feasibility of preoperative camrelizumab (an anti-PD-1 antibody) combined with MWA in the treatment of early-stage breast cancer.

METHODS

Sixty participants were randomized to preoperatively receive single-dose camrelizumab alone (n = 20), MWA alone (n = 20), or camrelizumab+MWA (n = 20). A random number table was used to allocate interventions. The primary outcome was the safety and feasibility of MWA combined with camrelizumab.

FINDINGS

Camrelizumab and MWA were well tolerated alone and in combination without delays in prescheduled surgery. No treatment-related grade III/IV adverse events were observed. Different from in the single-dose camrelizumab or MWA group, participants showed stable counts of blood cells after combination therapy. After combination therapy, peripheral CD8+ T cells showed enhanced cytotoxic and effect-memory functions. Clonal expansional CD8+ T cells showed higher cytotoxic activity and effector memory- and tumor-specific signatures than emergent clones after combination therapy. Enhanced interactions between clonal expansional CD8+ T cells and monocytes were observed, suggesting that monocytes contributed to the enhanced functions of clonal expansional CD8+ T cells. Major histocompatibility complex (MHC) class I-related pathways and interferon signaling pathways were activated in monocytes by combination therapy.

CONCLUSIONS

Camrelizumab combined with MWA was feasible for early-stage breast cancer. Peripheral CD8+ T cells were activated after combination therapy, dependent on monocytes with activated MHC class I pathways.

FUNDING

This study was supported by the Natural Science Foundation of Jiangsu Province (BK20230017).