Image-guided percutaneous ablation for the treatment of lung malignancies: current state of the art

Bronchoscopic treatment of early-stage peripheral lung cancer

PURPOSE OF REVIEW

This review article focuses on bronchoscopic treatment of early-stage peripheral lung cancer.

RECENT FINDINGS

Bronchoscopic treatment modalities have garnered considerable attention for early-stage lung cancer. Studies using photodynamic therapy, thermal vapor ablation, laser ablation, cryoablation, and intra-tumoral injection have recently been published. However, the evidence supporting these approaches largely derives from single-arm studies with small sample sizes. Based on the IDEAL-D framework, no technology has progressed passed the idea phase (1). The main weakness of these technologies to date is lack of evidence suggesting they can achieve local control. Presently, no bronchoscopic intervention for lung cancer has sufficient data to warrant its use as part of the standard of care.

SUMMARY

Despite notable progress, current technologies remain suboptimal, and there is insufficient evidence to support their use outside of a research setting.

The influence of respiratory movement on preoperative CT-guided localization of lung nodules

AIM

To evaluate the motion amplitude of lung nodules in different locations during preoperative computed tomography (CT)-guided localization, and the influence of respiratory movement on CT-guided percutaneous lung puncture.

MATERIALS AND METHODS

A consecutive cohort of 398 patients (123 men and 275 women with a mean age of 53.9 ± 10.7 years) who underwent preoperative CT-guided lung nodule localization from May 2021 to Apr 2022 were included in this retrospective study. The respiratory movement-related nodule amplitude in the cranial-caudal direction during the CT scan, characteristics of patients, lesions, and procedures were statistically analyzed. Univariate and multivariate logistic regression analyses were used to evaluate the influence of these factors on CT-guided localization.

RESULTS

The nodule motion distribution showed a statistically significant correlation within the upper/middle (lingular) and lower lobes (p<0.001). Motion amplitude was an independent risk factor for CT scan times (p=0.011) and procedure duration (p=0.016), but not for the technical failure rates or the incidence of complications. Puncture depth was an independent risk factor for the CT scan times, procedure duration, technical failure rates, and complications (p<0.01). Female, prone, and supine (as opposed to lateral) positions were significant protective factors for pneumothorax, while the supine position was an independent risk factor for parenchymal hemorrhage (p=0.025).

CONCLUSION

Respiratory-induced motion amplitude of nodules was greater in the lower lobes, resulting in more CT scan times/radiation dose and longer localization duration, but showed no statistically significant influence on the technical success rates or the incidence of complications during preoperative CT-guided localization.

Transbronchial cryoablation in peripheral lung parenchyma with a novel thin cryoprobe and initial clinical testing

BACKGROUND

Transbronchial cryoablation shows potential as a local therapy for inoperable peripheral lung cancer. However, its clinical application for peripheral pulmonary lesions has not been reported yet.

METHODS

An improved cryoprobe with an 8-mm-long, 1.9-mm-wide cryotip was used. Initially, the safety and effectiveness of this cryoprobe were assessed in an in vivo porcine model. Transbronchial cryoablation with 2 or 3 freeze-thaw cycles (10 min or 15 min in each freezing time) was performed in 18 pigs under CT monitoring. Radiological and pathological examinations were performed to evaluate the extent of cryoablation. Subsequently, nine patients with stage IA peripheral lung cancer or metastases underwent transbronchial cryoablation with this cryoprobe under the guidance of navigation bronchoscopy and cone-beam CT. Technical success, safety and outcomes were assessed.

RESULTS

36 cryoablation procedures were performed successfully without any major complications in the porcine model. The extent of cryoablation increased with freezing time and the number of freeze-thaw cycles, which peaked at 24 hours and then gradually decreased. Pathological results showed a change from massive haemorrhage at 24 hours to fibrous hyperplasia with chronic inflammation after 4 weeks. In the clinical trial, 10 cryoablations were performed on 9 tumours with a technical success rate of 100%. One mild treatment-related complication occurred. Of the nine tumours, seven achieved complete ablation, while two exhibited incomplete ablation and subsequent local progression at 6 months.

CONCLUSION

Our initial experience indicated that transbronchial cryoablation was a safe and feasible procedure for non-surgical peripheral stage IA lung cancer or pulmonary metastases.

TRIAL REGISTRATION NUMBER

ChiCTR2200061544.

2024 multidisciplinary consensus on image-guided lung tumor ablation from the Taiwan Academy of Tumor Ablation

In this article, the multidisciplinary team of the Taiwan Academy of Tumor Ablation, who have expertise in treating lung cancer, present their perspectives on percutaneous image-guided thermal ablation (IGTA) of lung tumors. The modified Delphi technique was applied to reach a consensus on clinical practice guidelines concerning ablation procedures, including a comprehensive literature review, selection of panelists, creation of a rating form and survey, and arrangement of an in-person meeting where panelists agreed or disagreed on various points. The conclusion was a final rating and written summary of the agreement. The multidisciplinary expert team agreed on 10 recommendations for the use of IGTA in the lungs. These recommendations include terms and definitions, line of treatment planning, modality, facility rooms, patient anesthesia settings, indications, margin determination, post-ablation image surveillance, qualified centers, and complication ranges. In summary, IGTA is a safe and feasible approach for treating primary and metastatic lung tumors, with a relatively low complication rate. However, decisions regarding the ablation technique should consider each patient's specific tumor characteristics.

[Ablation of liver tumors : From pre-interventional imaging to post-interventional assessment]

The aim of this article is to provide an overview on the most frequently applied image-guided, percutaneous, local ablative techniques for treatment of primary and secondary liver tumors. The technical procedures of microwave ablation (MWA) and radiofrequency ablation (RFA) are presented. The pre-interventional diagnostics, indications and feasibility are also discussed, taking the current national guidelines into consideration. Finally, treatment outcomes and recommendations on post-interventional imaging following local tumor ablation are presented.

High-Frequency Jet Ventilation Versus Spontaneous Respiration for Percutaneous Cryoablation of Lung Tumors: Comparison of Adverse Events and Procedural Efficiency

BACKGROUND. High-frequency jet ventilation (HFJV) facilitates accurate probe placement in percutaneous ablation of lung tumors but may increase risk for adverse events, including systemic air embolism. OBJECTIVE. The purpose of this study was to compare major adverse events and procedural efficiency of percutaneous lung ablation with HFJV under general anesthesia to spontaneous respiration (SR) under moderate sedation. METHODS. This retrospective study included consecutive adults who underwent CT-guided percutaneous cryoablation of one or more lung tumors with HFJV or SR between January 1, 2017, and May 31, 2023. We compared major adverse events (Common Terminology Criteria for Adverse Events grade ≥ 3) within 30 days postprocedure and hospital length of stay (HLOS) of 2 days or more using logistic regression analysis. We compared procedure time, room time, CT guidance acquisition time, CT guidance radiation dose, total radiation dose, and pneumothorax using generalized estimating equations. RESULTS. Overall, 139 patients (85 women, 54 men; median age, 68 years) with 310 lung tumors (82% metastases) underwent 208 cryoablations (HFJV, n = 129; SR, n = 79). HFJV showed greater rates than SR for the treatment of multiple tumors per session (43% vs 19%, respectively; p = .02) and tumors in a nonperipheral location (48% vs 24%, p < .001). Major adverse event rate was 8% for HFJV and 5% for SR (p = .46). No systemic air embolism occurred. HLOS was 2 days or more in 17% of sessions and did not differ significantly between HFJV and SR (p = .64), including after adjusting for probe number per session, chronic obstructive pulmonary disease, and operator experience (p = .53). Ventilation modalities showed no significant difference in procedure time, CT guidance acquisition time, CT guidance radiation dose, or total radiation dose (all p > .05). Room time was longer for HFJV than SR (median, 154 vs 127 minutes, p < .001). For HFJV, the median anesthesia time was 136 minutes. Ventilation modalities did not differ in the frequencies of pneumothorax or pneumothorax requiring chest tube placement (both p > .05). CONCLUSION. HFJV appears to be as safe as SR but had longer room times. HFJV can be used in complex cases without significantly impacting HLOS of 2 days or more, procedure time, or radiation exposure. CLINICAL IMPACT. Selection of the ventilation modality during percutaneous lung ablation should be based on patient characteristics and anticipated procedural requirements as well as operator preference.

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.

[Recent Advances in Diagnosis and Treatment Strategies for Multiple Primary Lung Cancer]

As the utilization of computed tomography in lung cancer screening becomes more prevalent in the post-pandemic era, the incidence of multiple primary lung cancer (MPLC) has surged in various countries and regions. Despite the continued application of advanced histologic and sequencing technologies in this research field, the differentiation between MPLC and intrapulmonary metastasis (IM) remains challenging. In recent years, the specific mechanisms of genetic and environmental factors in MPLC have gradually come to light. Lobectomy still predominates in the treatment of MPLC, but the observation that tumor-specific sublobar resection has not detrimentally impacted survival appears to be a viable option. With the evolution of paradigms, the amalgamated treatment, primarily surgical, is an emerging trend. Among these, stereotactic ablative radiotherapy (SABR) and lung ablation techniques have emerged as efficacious treatments for early unresectable tumors and control of residual lesions. Furthermore, targeted therapies for driver-positive mutations and immunotherapy have demonstrated promising outcomes in the postoperative adjuvant phase. In this manuscript, we intend to provide an overview of the management of MPLC based on the latest discoveries.
.

Imaging Follow-Up of Nonsurgical Therapies for Lung Cancer: AJR Expert Panel Narrative Review

Lung cancer continues to be the most common cause of cancer-related death worldwide. In the past decade, with the implementation of lung cancer screening programs and advances in surgical and nonsurgical therapies, the survival of patients with lung cancer has increased, as has the number of imaging studies that these patients undergo. However, most patients with lung cancer do not undergo surgical re-section, because they have comorbid disease or lung cancer in an advanced stage at diagnosis. Nonsurgical therapies have continued to evolve with a growing range of systemic and targeted therapies, and there has been an associated evolution in the imaging findings encountered at follow-up examinations after such therapies (e.g., with respect to posttreatment changes, treatment complications, and recurrent tumor). This AJR Expert Panel Narrative Review describes the current status of nonsurgical therapies for lung cancer and their expected and unexpected imaging manifestations. The goal is to provide guidance to radiologists regarding imaging assessment after such therapies, focusing mainly on non-small cell lung cancer. Covered therapies include systemic therapy (conventional chemotherapy, targeted therapy, and immunotherapy), radiotherapy, and thermal ablation.

Cryoablation combined with a clinical Chinese medicine for the treatment of lung cancer

Cryoablation has been clinically applied to the treatment of lung cancer, but cryoablation has the problem of incomplete tumor killing when the freezing dose is not enough, which may lead to tumor recurrence or metastasis. Therefore, cryoablation combined with other therapeutic options is usually suggested to achieve a complete cure for lung cancer. Clinical practices have shown that traditional Chinese medicine (TCM) treatment can improve the quality of life of patients with advanced lung cancer and prolong the postoperative survival time. However, the mechanism of the synergistic effect of Chinese medicine and cryotherapy, and the optimal treatment plan have not been clarified so far. Therefore, the effect of TCM particles on ice crystal growth and phase transition during cooling was investigated. In addition, we explored the optimized concentration and combination treatment sequence of TCM (lung care formula) and validated the optimal treatment protocol by establishing a mouse model of non-small cell lung cancer (NSCLC). In general, cryoablation combined with TCM is a useful treatment for lung cancer, which can effectively solve the problem of tumor recurrence after cryoablation.

Percutaneous ablation treatment in metastatic lung tumors: a single-center experience

BACKGROUND

In recent years, many studies have proven that percutaneous thermal ablation is an effective second-line treatment method with low complication rates in early-stage non-small cell lung carcinoma and lung metastases. Radiofrequency ablation and microwave ablation are commonly used for this purpose.

PURPOSE

To evaluate the factors affecting the success of the percutaneous thermal ablation treatment with technical success, complication rates, and long-term follow-up results in metastatic lung lesions.

MATERIAL AND METHODS

Computed tomography (CT)-guided percutaneous ablation was performed for 70 metastatic lung lesions in 35 patients (22 men, 13 women; mean age = 61.34 years; age range = 41-75 years). Radiofrequency ablation was performed in 53/70 (75.7%) lesions and microwave ablation in 17/70 (24.3%) lesions.

RESULTS

The technical success rate was 98.6%. Median overall survival, progression-free survival, and local recurrence-free survival of the patients were 33.9 months (range=25.6-42.1 months), 12 months (range=4.9-19.2 months), and 24.2 months (range=8.2-40.1 months), respectively. One- and two-year overall survival rates were 84% and 74%, respectively. Median progression-free survival times were 20.3 months and 11.4 months, respectively, according to the number of metastatic lung lesions being single and multiple, and the difference was statistically significant (P = 0.046). According to the number of lesions ≤3 and >3, the difference was also found statistically significant (P = 0.024) (14.3 months and 5.7 months, respectively).

CONCLUSION

In conclusion, CT-guided percutaneous thermal ablation is a safe and effective treatment method in metastatic lung lesions. The number of lesions is the most important factor in predicting treatment success.

Ablation of pulmonary neoplasms: review of literature and future perspectives

Thermal ablation is a minimally invasive technology used to treat many types of tumors, including lung cancer. Specifically, lung ablation has been increasingly performed for unsurgical fit patients with both early-stage primi-tive lung cancer and pulmonary metastases. Image-guided available techniques include radiofrequency ablation, microwave ablation, cryoablation, laser ablation and irreversible electroporation. Aim of this review is to illustrate the major thermal ablation modalities, their indications and contraindications, complications, outcomes and notably the possible future challenges.

Primary and Metastatic Lung Cancer: Rationale, Indications, and Outcomes of Thermal Ablation

The widespread use of imaging as well as the efforts conducted through screening campaigns has dramatically increased the early detection rate of lung cancer. Historically, the management of lung cancer has heavily relied on surgery. However, the increased proportion of patients with comorbidities has given significance to less invasive therapeutic options like minimally invasive surgery and image-guided thermal ablation, which could precisely target the tumor without requiring general anesthesia or a thoracotomy. Thermal ablation is considered low-risk for lung tumors smaller than 3 cm that are located in peripheral lung and do not involve major blood vessels or airways. The rationale for ablative therapies relies on the fact that focused delivery of energy induces cell death and pathologic necrosis. Image-guided percutaneous thermal ablation therapies are established techniques in the local treatment of hepatic, renal, bone, thyroid and uterine lesions. In the lung, and specifically in the setting of metastatic disease, the 3 main indications for lung ablation are to serve as (1) curative intent, (2) as a strategy to achieve a chemo-holiday in oligometastatic disease, and (3) in oligoprogressive disease. Following these premises, the current paper aims to review the rationale, indications, and outcomes of thermal ablation as a form of local therapy in the treatment of primary and metastatic lung disease.

The safety and feasibility of three-dimensional visualization planning system for CT-guided microwave ablation of stage I NSCLC (diameter ≤2.5 cm): A pilot study

Background

Microwave ablation (MWA) of lung tumors is a technique that is dependent on the ablationist's level of expertise. The selection of the optimum puncture path and determination of appropriate ablative parameters is the key to the success and safe of the procedure. The objective of this study was to describe the clinical use of a novel three-dimensional visualization ablation planning system (3D-VAPS) for aided MWA of stage I non-small cell lung cancer (NSCLC).

Methods

This was a single-arm, single-center, retrospective study. From May 2020 to July 2022, 113 consented patients with stage I NSCLC received MWA treatment in 120 MWA sessions. The 3D-VAPS was used to determine that: (1) the overlap between the gross tumor region and simulated ablation; (2) the proper posture and appropriate puncture site on the surface of the body; (3) the puncture path; and (4) presetting preliminarily ablative parameters. Patients were monitored with contrast-enhanced CT scans at 1, 3, and 6 months, as well as every 6 months following that. The primary endpoints were technical success and a complete ablation rate. Local progression-free survival (LPFS), overall survival (OS), and comorbidities were secondary study objectives.

Results

The mean diameter of tumors was 1.9 ± 0.4 cm (range 0.9-2.5 cm). The mean duration was 5.34 ± 1.28 min (range 3.0-10.0 min). The mean power output was 42.58 ± 4.23 (range 30.0-50.0W). The median follow-up time was 19.0 months (6.0-26.0 months). The technical success rate was 100%. Three-month after the procedure, the complete ablation rate was 97.35%. 6, 9, 12, and 24 months LPFS rates were 100%, 98.23%, 98.23%, and 96.46%, respectively. One-year and 2-year OS rates were 100% and 100%. There were no patients who died both during the procedure and after the MWA of 30 days. The complications after MWA included pneumothorax (38.33%), pleural effusion (26.67%), intrapulmonary hemorrhage (31.67%), and pulmonary infection (2.50%).

Conclusions

This research describes and confirms that 3D-VAPS is a feasibility and safe method for MWA of stage I NSCLC treatment. 3D-VAPS may be helpful to optimize the puncture path, assess reasonable ablative parameters, and minimize complications.

Multiple primary lung cancer: Updates of clinical management and genomic features

In recent decades, multiple primary lung cancer (MPLC) has been increasingly prevalent in clinical practice. However, many details about MPLC have not been completely settled, such as understanding the driving force, clinical management, pathological mechanisms, and genomic architectures of this disease. From the perspective of diagnosis and treatment, distinguishing MPLC from lung cancer intrapulmonary metastasis (IPM) has been a clinical hotpot for years. Besides, compared to patients with single lung lesion, the treatment for MPLC patients is more individualized, and non-operative therapies, such as ablation and stereotactic ablative radiotherapy (SABR), are prevailing. The emergence of next-generation sequencing has fueled a wave of research about the molecular features of MPLC and advanced the NCCN guidelines. In this review, we generalized the latest updates on MPLC from definition, etiology and epidemiology, clinical management, and genomic updates. We summarized the different perspectives and aimed to offer novel insights into the management of MPLC.

Image-Guided Percutaneous and Transarterial Therapies for Primary and Metastatic Lung Cancer

Lung cancer is the leading cause of cancer mortality in the world. A significant proportion of patients with lung cancer are not candidates for surgery and must resort to other treatment alternatives. Rapid technological advancements in fields like interventional radiology have paved the way for valid treatment modalities like image-guided percutaneous and transarterial therapies for treatment of both primary and metastatic lung cancer. The rationale of ablative therapies relies on the fact that focused delivery of energy induces tumor destruction and pathological necrosis. Image-guided percutaneous thermal ablation therapies are established techniques in the local treatment of hepatic, renal, bone, thyroid, or uterine lesions. In the lung, the 3 main indications for lung ablation include local curative intent, a strategy to achieve a chemoholiday in oligometastatic disease, and recently, oligoprogressive disease. Transarterial therapies include a set of catheter-based treatments that involve delivering embolic and/or chemotherapeutic agents directed into the target tumor via the supplying arteries. This article provides a comprehensive review of the various techniques available and discusses their applications and associated complications in primary and metastatic lung cancer.

Issues and prospects of image-guided thermal ablation in the treatment of primary and metastatic lung tumors

The precise local minimally invasive or noninvasive treatment represents the important orientation for advancing the treatment of pulmonary malignant tumors. New local treatment methods have emerged as solutions to the shortcomings of minimally invasive or local treatment methods. Image-guided thermal ablation (IGTA) comes with the characteristics such as more accurate localization, less trauma, more definite efficacy, higher safety, stronger repeatability, fewer complications, and lower cost in treating lung tumors. This paper investigates the existing problems of IGTA in the treatment of lung tumors and puts forward the orientation of studies.

Image-guided percutaneous ablation for lung malignancies

Image-guided percutaneous lung ablation has proven to be an alternative and effective strategy in the treatment of lung cancer and other lung malignancies. Radiofrequency ablation, microwave ablation, and cryoablation are widely used ablation modalities in clinical practice that can be performed along or combined with other treatment modalities. In this context, this article will review the application of different ablation strategies in lung malignancies.

Microwave ablation with local pleural anesthesia for subpleural pulmonary nodules: our experience

Objectives

To explore the efficacy and safety of local pleural anesthesia (LPA) for relieving pain during microwave ablation (MWA) of pulmonary nodules in the subpleural regions.

Materials and Methods

From June 2019 to December 2021, 88 patients with 97 subpleural nodules underwent percutaneous CT-guided MWA. Patients were divided into two groups according to whether LPA was applied; 53 patients with local pleural anesthesia during MWA; and 35 patients with MWA without LPA. The differences in technical success, pre-and post- and intra-operative visual analog scale (VAS) pain scores, complications of the procedure, and local progression-free survival (LPFS) between the two groups were assessed. Thus, to evaluate the efficacy and safety of MWA combined with LPA for treating subpleural nodules.

Results

In this study, the procedures in all patients of both groups achieved technical success according to pre-operative planning. There was no statistically significant difference in the pre-operative VAS pain scores between the two groups. Intra-operative VAS scores were significantly higher in the non-LPA (NLPA) group than in the LPA group. They remained significantly higher in the NLPA group than in the LPA group during the short postoperative period. Analgesics were used more in the NLPA group than in the LPA group intra- and postoperatively, with a statistically significant difference, especially during the MWA procedures. The overall LPFS rates were 100%, 98.333%, 98.333%, and 98.333% at 1, 3, 6, and 12 months postoperatively in the LPA group and 100%, 97.297%, 94.595%, and 94.595% postoperatively in the NLPA group, respectively. Tumor recurrence occurred in one and two patients with lung adenocarcinoma in the LPA and NLPA groups. The incidence of pneumothorax was significantly higher in the NLPA group (25,714%, 9/35) than in the LPA group (15.094%, 8/53), and there were three cases of pleural effusion (blood collection) and one case of pulmonary hemorrhage in the NLPA group.

Conclusion

Percutaneous CT-guided MWA is a safe and effective treatment for subpleural pulmonary nodules. Applying a combined LPA technique can reduce the patient’s pain and complications during and after the MWA. The long-term efficacy must be verified in more patients and a longer follow-up.

Current trends in image-guided chest interventions

Interventional radiology (IR) is a rapidly expanding medical subspecialty and refers to a range of image‐guided procedural techniques. The image guidance allows real‐time visualization and precision placement of a needle, catheter, wire and device to deep body structures through small incisions. Advantages include reduced risks, faster recovery and shorter hospital stays, lower costs and less patient discomfort. The range of chest interventional procedures keeps on expanding due to improved imaging facilities, better percutaneous assess devices and advancing ablation and embolization techniques. These advances permit procedures to be undertaken safely, simultaneously and effectively, hence escalating the role of IR in the treatment of chest disorders. This review article aims to cover the latest developments in some image‐guided techniques of the chest, including thermal ablation therapy of lung malignancy, targeted therapy of pulmonary embolism, angioplasty and stenting of mediastinal venous/superior vena cava occlusion, pulmonary arteriovenous malformation treatment and bronchial artery embolization for haemoptysis.

Synchronous Microwave Ablation Combined With Cisplatin Intratumoral Chemotherapy for Large Non-Small Cell Lung Cancer

Background

Microwave ablation (MWA) and intratumoral chemotherapy (ITC) are useful for treating tumors in animal models; however, their clinical use in patients with large non−small cell lung cancer (NSCLC) remains unknown. This retrospective study aimed to evaluate preliminary outcomes of MWA + ITC for large NSCLC.

Methods

From November 2015 to April 2020, a total of 44 NSCLC patients with a mean lesion diameter of 6.1 ± 1.5 cm were enrolled and underwent synchronous MWA + ITC procedures. The primary endpoint was local progression-free survival (LPFS); secondary endpoints were progression-free survival (PFS), complications, overall survival (OS), and associated prognostic factors.

Results

The median follow-up time was 19.0 months. At the 1-month CT scan, complete tumor ablation was observed in 47.7% of cases. Median LPFS was 12.1 months; 1-, 2-, and 3-year LPFS rates were 51.2%, 27.9%, and 13.6%, respectively. A shorter LPFS was significantly associated with large lesions (HR 1.23, 95% CI 1.02–1.49; p = 0.032). Median PFS was 8.1 months; 1-, 2-, and 3-year PFS rates were 29.5%, 18.2%, and 9.1%, respectively. LPFS was significantly superior to PFS (p = 0.046). Median OS was 18.8 months. The 1-, 2-, 3-, and 5-year OS rates were 65.9%, 43.2%, 26.4%, and 10.0%, respectively. In univariate comparisons, high performance status (PS) score, smoking, and larger lesions were significantly correlated with poor survival. In multivariate analysis, advanced age, higher PS score, higher stage, larger lesion, and prior systematic treatment were independent prognostic factors for shorter OS. Adverse events were well tolerated and all patients recovered after appropriate intervention.

Conclusions

MWA + ITC is a safe and effective new modality of local treatment for large NSCLC and can significantly prolong LPFS.

A Systematic Review and Meta-analysis of Patient Survival and Disease Recurrence Following Percutaneous Ablation of Pulmonary Metastasis

BACKGROUND

Pulmonary metastasectomy has been widely adopted in the treatment of metastatic disease. In recent years image guided ablation has seen increased use in the treatment of thoracic malignancies. The objective of this study was to evaluate oncological outcomes following percutaneous ablation (PA) of pulmonary metastasis.

METHODS

A comprehensive search of the PubMed, MEDLINE and EMBASE databases from January 2000 to August 2021 was performed to identify studies evaluating patient survival following ablation of lung metastasis. Pooled outcomes have been presented with a random effects model to assess primary outcomes of overall survival, progression free survival and 1-year local control. Secondary outcomes included procedural mortality, major complications, and the incidence of pneumothorax.

RESULTS

A total of 24 studies were identified. The pooled median overall survival was 5.13 [95% confidence interval (CI): 4.37-6.84] years, and the 1-, 3-, 5-year progression free survival rates were 53%, 26% and 20% respectively. The 1-year local control rate was 91% (95%CI: 86-95%). Periprocedural mortality was rare (0%; 95%CI: 0-1%), as were major complications excluding pneumothorax (1%; 95%CI: 1-2%). Pneumothorax developed in 44% of ablation sessions, although only half of these required chest tube placement. Most patients were able to be discharged day one post-procedurally.

CONCLUSION

PA demonstrates high overall, progression free and local tumour survival in patients with lung metastasis. Complications and mortality are also rare. Consideration of its use should be made in a tumour board meeting in conjunction with surgical and radiotherapy perspectives for targeted local control of metastases.

Factors Associated with Pulmonary Function Changes in Patients Undergoing Microwave Ablation for Pulmonary Ground-Glass Nodules

Purpose: Microwave ablation has become an alternative treatment for pulmonary ground-glass nodules (GGN) and is widely accepted by clinicians. However, its effect on lung function remains unknown. Therefore, this retrospective study aimed to explore pulmonary function changes and associated risk factors in patients undergoing computed tomography (CT)-guided microwave ablation (MWA) for treating pulmonary GGN. Materials and Methods: Thirty-five patients diagnosed with pulmonary GGN on thin-layer chest CT and enhanced CT were examined. Patients unable or unwilling to undergo thoracoscopic surgery underwent CT-guided simultaneous percutaneous core needle biopsy and MWA. Pulmonary function tests (PFT) were performed before ablation and 3 days and 6 months post-ablation. Forced expiratory volume in one second (FEV1), FEV1%, forced vital capacity (FVC), maximal voluntary ventilation (MVV), and peak expiratory flow (PEF) values pre- and post-MWA were analysed. Linear regression analysis was used to examine the correlation between ablation volume and changes in PFT findings 3 days post-ablation. Associations between patient characteristics, rates of postoperative complications, and PFT findings were analysed. Results: Forty-eight lesions were completely ablated and examined intraoperatively. There were significant differences in pre- and post-operative PFT findings on day 3 but not at 6 months. The mean ablation volume after 3 days of 11.4 ± 6.3 cm³ was positively correlated with changes in FEV1, MVV, and PEF values. Patients' age (mean, 59.4 ± 13.0 years) positively correlated with changes in PEF values. The rates of change in FVC and MVV values were significantly higher with multiple pulmonary nodules than with isolated pulmonary nodule. PFT findings were similar between patients who experienced or did not experience complications (eg, pneumothorax and pleural effusion). Conclusions: Pulmonary function could be impaired shortly after MWA. PFT findings may correlate with age, ablation volume, and number of ablated lesions. In most patients, pulmonary function returned to the preoperative state after 6 months.

Transbronchial lung parenchyma cryoablation with a novel flexible cryoprobe in an in vivo porcine model

PURPOSE

The purpose of this study was to evaluate the feasibility and safety of transbronchial cryoablation with a novel flexible cryoprobe using nitrogen as the refrigerant in an in vivo porcine model of lung parenchyma.

MATERIALS AND METHODS

A novel flexible cryoprobe using nitrogen as the refrigerant was used for transbronchial cryoablation of lung parenchyma in six normal female pigs. The cryoprobe was delivered to the distal bronchus in the bilateral porcine lungs via the bronchoscopic working channel under virtual bronchoscopy guidance. The position was confirmed with real-time computed tomography (CT). The whole procedure included two freeze-thaw cycles (15 min and 2 min, respectively). CT images were obtained during cryoablation and at 24 h, one week, two weeks and four weeks after the treatment to assess the effectiveness and safety of the procedure. Ablation zone tissue samples were obtained at 24 h and four weeks after the cryoablation for further histopathological analysis.

RESULTS

All ablation procedures (12/12; 100%) were performed successfully. No major complications occurred during the procedure or the observation period. The ablation zones were clearly depicted on CT with a maximal ablation zone volume at 24 h (21.88 ± 12.61 [SD] cm³) compared to 3.64 ± 2.06 (SD) cm³ and 10.73 ± 3.84 (SD) cm³ at the end of the 1st and 2nd freeze-thaw cycles, respectively (P < 0.001). Histopathological analysis revealed that a coagulative necrotic zone was formed along the target bronchus, with obvious vascular occlusion and hemorrhage 24 h after treatment. The lesions gradually formed fibrosis after four weeks.

CONCLUSION

The novel flexible bronchoscopy-guided cryoablation is a feasible, safe and effective modality in an in vivo porcine model of peripheral normal lung parenchyma, suggesting potential capabilities for the treatment of peripheral lung cancer in humans.

Lung Thermal Ablation: Comparison between an Augmented Reality Computed Tomography (CT) 3D Navigation System (SIRIO) and Standard CT-Guided Technique

Simple Summary

Lung cancer is the leading cause of cancer mortality worldwide. In recent years, numerous technologies have been used to perform image-guided percutaneous thermal ablation, mainly including radiofrequency ablation, microwave ablation, and cryoablation. These image-guided ablation techniques have emerged as a safe, cost-effective, minimally invasive treatment alternative for patients who do not require surgery. Procedural planning, monitoring, and lesion targeting are generally performed with the help of computed tomography; navigation systems are emerging as valid tool to reduce procedural time and radiation dose administration. In the present paper, we investigate the efficacy of an optical-based navigation system (SIRIO) to perform lung thermal ablation. SIRIO proved to be a reliable and effective tool when performing CT-guided LTA, displaying a significant decrease in the number of required CT scans, procedure time, and radiation doses administered to patients.

Abstract

(1) Background: The aim of this retrospective study is to assess safety and efficacy of lung radiofrequency (RFA) and microwave ablation (MWA) using an augmented reality computed tomography (CT) navigation system (SIRIO) and to compare it with the standard CT-guided technique. (2) Methods: Lung RFA and MWA were performed with an augmented reality CT 3D navigation system (SIRIO) in 52 patients. A comparison was then performed with a group of 49 patients undergoing the standard CT-guided technique. All the procedures were divided into four groups based on the lesion diameter (>2 cm or ≤2 cm), and procedural time, the number of CT scans, radiation dose administered, and complications rate were evaluated. Technical success was defined as the presence of a “ground glass” area completely covering the target lesion at the immediate post-procedural CT. (3) Results: Full technical success was achieved in all treated malignant lesions for all the considered groups. SIRIO-guided lung thermo-ablations (LTA) displayed a significant decrease in the number of CT scans, procedure time, and patients’ radiation exposure (p < 0.001). This also resulted in a dosage reduction in hypnotics and opioids administrated for sedation during LTA. No significant differences were observed between the SIRIO and non-SIRIO group in terms of complications incidence. (4) Conclusions: SIRIO is an efficient tool to perform CT-guided LTA, displaying a significant reduction (p < 0.001) in the number of required CT scans, procedure time, and patients’ radiation exposure.