Technical safety and efficacy of a blunt-tip microwave ablation electrode for CT-guided ablation of pulmonary ground-glass opacity nodules

Lung microwave ablation: Post-procedure imaging features and evolution of pulmonary ground-glass nodule-like lung cancer

PURPOSE

To retrospectively examine the imaging characteristics of chest-computed tomography (CT) following percutaneous microwave ablation (MWA) of the ground-glass nodule (GGN)-like lung cancer and its dynamic evolution over time.

MATERIALS AND METHODS

From June 2020 to May 2021, 147 patients with 152 GGNs (51 pure GGNs and 101 mixed GGNs, mean size 15.0 ± 6.3 mm) were enrolled in this study. One hundred and forty-seven patients underwent MWA procedures. The imaging characteristics were evaluated at predetermined time intervals: immediately after the procedure, 24-48 h, 1, 3, 6, 12, and ≥18 months (47 GGNs).

RESULTS

This study population included 147 patients with 152 GGNs, as indicated by the results: 43.5% (66/152) adenocarcinoma in situ, 41.4% (63/152) minimally invasive adenocarcinoma, and 15.1% (23/152) invasive adenocarcinoma. Immediate post-procedure tumor-level analysis revealed that the most common CT features were ground-glass opacities (93.4%, 142/152), hyperdensity within the nodule (90.7%, 138/152), and fried egg sign or reversed halo sign (46.7%, 71/152). Subsequently, 24-48 h post-procedure, ground-glass attenuations, hyperdensity, and the fried egg sign remained the most frequent CT findings, with incidence rates of 75.0% (114/152), 71.0% (108/152), and 54.0% (82/152), respectively. Cavitation, pleural thickening, and consolidation were less frequent findings. At 1 month after the procedure, consolidation of the ablation region was the most common imaging feature. From 3 to 12 months after the procedure, the most common imaging characteristics were consolidation, involutional parenchymal bands and pleural thickening. At ≥18 months after the procedure, imaging features of the ablation zone revealed three changes: involuting fibrosis (80.8%, 38/47), consolidation nodules (12.8%, 6/47), and disappearance (6.4%, 3/47).

CONCLUSIONS

This study outlined the anticipated CT imaging characteristics of GGN-like lung cancer following MWA. Diagnostic and interventional radiologists should be familiar with the expected imaging characteristics and dynamic evolution post-MWA in order to interpret imaging changes with a reference image.

Microwave ablation with a blunt-tip antenna for pulmonary ground-glass nodules: a retrospective, multicenter, case-control study

PURPOSE

A previous small-sample study verified that a blunt-tip antenna reduced hemorrhage during microwave ablation. We conducted this large-sample, multicenter, case-control study to further verify the efficacy and safety of microwave ablation with a blunt-tip antenna for ground-glass nodules.

MATERIALS AND METHODS

Patients with pulmonary ground-glass nodules were treated with either a sharp-tip (Group A) or blunt-tip antenna (Group B). A total of 147 and 150 patients were retrospectively allocated to Groups A and Group B, respectively. Group A patients underwent 151 procedures, and Group B patients underwent 153 procedures. We assessed the technical success, technique efficacy, and complications.

RESULTS

Technical success and overall technique efficacy were achieved in all patients (100%). Major complications of pneumothorax were more commonly observed in Group A than in Group B (19.7% vs. 2.0%, p < 0.001). Minor complications, such as intrapulmonary hemorrhage (2.0% vs. 9.5%, p = 0.005) and hemothorax (0.0% vs. 2.7%, p = 0.049), occurred less frequently in Group B compared to Group A.

CONCLUSION

In the treatment of ground-glass nodules, microwave ablation with a blunt-tip antenna had equal efficacy compared to microwave ablation with a sharp-tip antenna but had a decreased number of hemorrhage and hemothorax complications.

Microwave ablation for the treatment of peripheral ground-glass nodule-like lung cancer: Long-term results from a multi-center study

Introduction

Microwave ablation (MWA) is an effective and safe approach for the treatment of ground-glass nodule (GGN)-like lung cancer, but long-term follow-up is warranted. Therefore, this multi-center retrospective study aimed to evaluate the results of MWA for the treatment of peripheral GGN-like lung cancer with a long-term follow-up.

Materials and Methods

From June 2013 to January 2018, a total of 87 patients (47 males and 40 females, mean age 64.6 ± 10.2 years) with 87 peripheral lung cancer lesions showing GGN (mean long axis diameter, 17 ± 5 mm) underwent computed tomography (CT)-guided percutaneous MWA. All GGN-like lung cancers were histologically verified. The primary endpoints were local progression-free survival (LPFS) and overall survival (OS). The secondary endpoints were cancer-specific survival (CSS) and complications.

Results

During a median follow-up of 65 months, both the 3-year and 5-year LPFS rates were 96.6% and 96.6%. The OS rate was 94.3% at 3 years and 84.9% at 5 years, whereas the 3-year and 5-year CSS rates were 100% and 100%, respectively. No periprocedural deaths were observed. Complications were observed in 49 patients (51.6%). Grade 3 or higher complications included pneumothorax, pleural effusion, hemorrhage, and pulmonary infection, which were identified in ten (10.5%), two (2.1%), two (2.1%), and one (1.1%) patient, respectively.

Conclusions

CT-guided percutaneous MWA is an effective, safe, and potentially curative treatment regimen for GGN-like lung cancer.

Facilitating combined biopsy and percutaneous microwave ablation of pulmonary ground-glass opacities using lipiodol localisation

OBJECTIVES

Whether preoperative localisation is necessary and valuable for the microwave ablation (MWA) of small pulmonary lesions with ground-glass opacity (GGO) remains unclear. This study aimed to explore the role of the Chiba needle and lipiodol localisation techniques in facilitating MWA and biopsy.

METHODS

This retrospective before-after study included patients with GGOs who underwent conventional MWA and biopsy treatment in our hospital between January 2018 and December 2019 (group A) or who underwent the Chiba needle and lipiodol localisation treatment before MWA and biopsy between January 2020 and December 2020 (group B). The characteristics of each patient and GGO lesion were collected and analysed to evaluate the safety and effectiveness of the localisation technique.

RESULTS

A total of 122 patients with 152 GGOs and 131 patients with 156 GGOs underwent MWA and biopsy in groups A and B, respectively. The primary technique efficacy rate of MWA differed significantly between the two groups (A vs. B: 94.1% vs. 99.4%; p = 0.009). The positive biopsy rate in the two groups was determined by the difference (A vs. B: 93.4% vs. 98.1%; p = 0.042). The incidence of complications did not increase in group B.

CONCLUSIONS

Compared with the unmarked group, the Chiba needle and lipiodol localisation technique improved the positive rate of biopsy and the initial effective rate of MWA, without significantly increasing the complication rate.

KEY POINTS

• The localisation of the Chiba needle and lipiodol could improve the positive biopsy rate and the initial effective rate of MWA. • The localisation of the Chiba needle and lipiodol does not affect the subsequent MWA and biopsy and does not increase the incidence of pneumothorax and haemorrhage.

Comparative Evaluation of 2 Different Percutaneous Techniques of Simultaneous Needle Biopsy With Microwave Ablation of Suspected Malignant Pulmonary Nodules

Background: To compare the safety and efficacy of 2 different computed tomography-guided puncture techniques for simultaneous needle biopsy and microwave ablation of suspected malignant pulmonary nodules. Methods: This retrospective comparative before-and-after study analyzed the data of 81 patients (each with a suspected malignant pulmonary nodule) who underwent computed tomography-guided needle biopsy with simultaneous microwave ablation between September 2016 and September 2021. In group A, 41 patients (41 pulmonary nodules) underwent microwave ablation immediately through the biopsy channel, whereas in group B, 40 patients (40 pulmonary nodules) underwent computed tomography-guided percutaneous needle biopsy and microwave ablation through separate needle channels. Clinical data, technical success rates, complications, and short-term efficacy were compared between the groups to evaluate the advantages and disadvantages of both techniques. Results: Of the 81 patients, 78 successfully underwent needle biopsy and microwave ablation, with a technical success rate of 96.3%. The incidence of pneumothorax was 56.1% (23 out of 41) and 30% (12 out of 40) in groups A and B, respectively, while that of chest pain was 34.1% (14 out of 41) and 40% (16 out of 40) in groups A and B, respectively. The differences were statistically insignificant (p = .127 and p = .759). However, the incidence of hemoptysis was 39.0% (16 out of 41) and 17.5% (7 out of 40), respectively, which was statistically significant (P = .015). Air embolism, bronchopleural fistula, and needle implantation metastasis were not observed in both groups. At a 6-month follow-up, there were no other complications in both groups, and complete ablation was observed in all cases. Conclusion: Computed tomography-guided biopsy combined with microwave ablation is safe and effective for the treatment of suspected malignant pulmonary nodules, and clinicians can use both techniques.

Synchronous computed tomography-guided percutaneous biopsy and microwave ablation for highly suspicious malignant lung ground-glass opacities adjacent to mediastinum

BACKGROUND

This retrospective study aimed to assess the safety and efficacy of synchronous biopsy and microwave ablation (MWA) for highly suspected malignant lung ground-glass opacities (GGOs) adjacent to the mediastinum (distance ≤10 mm).

MATERIALS AND METHODS

Ninety patients with 98 GGOs (diameter range, 6-30 mm), located within 10 mm of the mediastinum, underwent synchronous biopsy and MWA at a single institution from 1 May 2020, to 31 October 2021 and were enrolled in this study. Synchronous biopsy and MWA involving the completion of the biopsy and MWA in a single procedure was performed. Safety, technical success rate, and local progression-free survival (LPFS) were evaluated. The risk factors for local progression were calculated using the Mann-Whitney U test.

RESULTS

The technical success rate was 97.96% (96/98 patients). The LPFS rates at 3, 6, and 12 months were 95.0%, 90.0%, and 82.0%, respectively. The diagnostic rate of biopsy-proven malignancy was 72.45% (n = 71/98). Invasion of lesions into the mediastinum was a risk factor for local progression (p = 0.0077). The 30-day mortality rate was 0. The major complications were pneumothorax (13.27%), ventricular arrhythmias (3.06%), pleural effusion (1.02%), hemoptysis (1.02%), and infection (1.02%). Minor complications included pneumothorax (30.61%), pleural effusion (24.49%), hemoptysis (18.37%), ventricular arrhythmias (11.22%), structural changes in adjacent organs (3.06%), and infection (3.06%).

CONCLUSIONS

Synchronous biopsy and MWA was effective for treating GGOs adjacent to the mediastinum without severe complications (Society of Interventional Radiology classification E or F). Invasion of lesions into the mediastinum was identified as a risk factor for local progression.

Cost and effectiveness of microwave ablation versus video-assisted thoracoscopic surgical resection for ground-glass nodule lung adenocarcinoma

Purpose

To retrospectively evaluate the cost and effectiveness in consecutive patients with ground-glass nodules (GGNs) treated with video-assisted thoracoscopic surgery (VATS; i.e., wedge resection or segmentectomy) or microwave ablation (MWA).

Materials and methods

From May 2017 to April 2019, 204 patients who met our study inclusion criteria were treated with VATS (n = 103) and MWA (n = 101). We calculated the rate of 3-year overall survival (OS), local progression-free survival (LPFS), and cancer−specific survival (CSS), as well as the cost during hospitalization and the length of hospital stay.

Results

The rates of 3-year OS, LPFS, and CSS were 100%, 98.9%, and 100%, respectively, in the VATS group and 100%, 100% (p = 0.423), and 100%, respectively, in the MWA group. The median cost of VATS vs. MWA was RMB 54,314.36 vs. RMB 21,464.98 (p < 0.001). The length of hospital stay in the VATS vs. MWA group was 10.0 vs. 6.0 d (p < 0.001).

Conclusions

MWA had similar rates of 3-year OS, LPFS, and CSS for patients with GGNs and a dramatically lower cost and shorter hospital stay compared with VATS. Based on efficacy and cost, MWA provides an alternative treatment option for patients with GGNs.

Fusion of CT images and clinical variables based on deep learning for predicting invasiveness risk of stage I lung adenocarcinoma

PURPOSE

To develop a novel multimodal data fusion model by incorporating computed tomography (CT) images and clinical variables based on deep learning for predicting the invasiveness risk of stage I lung adenocarcinoma that manifests as ground-glass nodules (GGNs), and compare the diagnostic performance of it with that of radiologists.

METHODS

A total of 1946 patients with solitary and histopathologically confirmed GGNs with maximum diameter less than 3 cm were retrospectively enrolled. The training dataset containing 1704 GGNs was augmented by resampling, scaling, random cropping, etc., to generate new training data. A multimodal data fusion model based on residual learning architecture and two multilayer perceptron with attention mechanism combining CT images with patient general data and serum tumor markers was built. The distance-based confidence scores (DCS) were calculated and compared among multimodal data models with different combinations. An observer study was conducted and the prediction performance of the fusion algorithms was compared with that of the two radiologists by an independent testing dataset with 242 GGNs.

RESULTS

Among the whole GGNs, 606 GGNs are confirmed as invasive adenocarcinoma (IA) and 1340 are non-IA. The proposed novel multimodal data fusion model combining CT images, patient general data and serum tumor markers achieved the highest accuracy (88.5%), Area under a ROC curve (AUC) (0.957), F1 (81.5%), F1_weighted (81.9%) and Matthews correlation coefficient (MCC) (73.2%) for classifying between IA and non-IA GGNs, which was even better than the senior radiologist's performance (accuracy, 86.1%). In addition, the DCSs for multimodal data suggested that CT image had a stronger influence (0.9540) quantitatively than general data (0.6726) or tumor marker (0.6971).

CONCLUSION

This study demonstrated that the feasibility of integrating different types of data including CT images and clinical variables, and the multimodal data fusion model yielded higher performance for distinguishing IA from non-IA GGNs. This article is protected by copyright. All rights reserved.

Computed tomography-guided microwave ablation for non-small cell lung cancer patients on antithrombotic therapy: a retrospective cohort study

BACKGROUND

For non-small cell lung cancer (NSCLC) patients on antithrombotic therapy who are treated with microwave ablation (MWA), the transient interruption of antithrombotic agents may increase the risk of thromboembolism, and continuation of antithrombotic agents may increase the risk of intraprocedural hemorrhage. This retrospective cohort study aimed to explore the safety of MWA in patients with NSCLC on antithrombotic therapy.

METHODS

A total of 572 patients with NSCLC (antithrombotic therapy group: n=84, Group A; control group: n=488, Group B) who received MWA were included. Antithrombotic agent use was suspended before MWA and resumed as soon as possible after MWA. Hemorrhagic (hemothorax and hemoptysis) and thromboembolic complications (pulmonary embolism, cerebral infarction, and angina) were compared. Logistic regression analyses were used to investigate the predictors of hemorrhagic complications after MWA.

RESULTS

Hemorrhagic complications occurred in 8 participants (9.5%) from Group A and 33 participants (6.8%) from Group B, and no statistically significant difference was found (P=0.365). There were 3 participants (0.5%) who developed thromboembolic complications, including 1 case (1.2%, 1/84) of pulmonary embolism in Group A, and 2 cases (0.4%, 2/488) of cerebral infarction or angina in Group B; no significant difference was found (P=0.923). In the subgroup analyses of Group A, no statistically significant difference of hemorrhagic (P>0.999) or thromboembolic complications (P>0.999) was found between patients who received and did not receive bridging anticoagulation with heparin. Logistic regression analyses revealed that direct contact of a tumor with vessels ≥2 mm was a predictor of hemorrhagic complications [hazard ratio (HR) =2.318; 95% confidence interval (CI): 1.215-4.420; P=0.011], while antithrombotic therapy was irrelevant.

CONCLUSIONS

With the appropriate cessation and resumption of antithrombotic agents, patients with NSCLC on antithrombotic therapy have comparable incidence rates of hemorrhagic and thromboembolic complications after MWA to those of patients who are not on antithrombotic therapy. Therefore, with appropriate cessation, MWA appears to generally be safe for NSCLC patients on antithrombotic therapy.