Efficacy and safety of thermal ablation of lung malignancies: A Network meta-analysis

The 'Liaisons dangereuses' Between Lung Cancer and Interstitial Lung Diseases: A Focus on Acute Exacerbation

Patients with interstitial lung disease (ILD) are about five times more likely to develop lung cancer than those without ILD. The presence of ILD in lung cancer patients complicates diagnosis and management, resulting in lower survival rates. Diagnostic and treatment procedures needed for cancer can increase the risk of acute exacerbation (AE), one of the most severe complications for these patients. Bronchoscopic techniques are generally considered safe, but they can trigger AE-ILD, particularly after cryoprobe biopsies. Surgical procedures for lung cancer, including lung biopsies and resections, carry an elevated risk of AE-ILD. Postoperative complications and mortality rates highlight the importance of meticulous surgical planning and postoperative care. Furthermore, cancer treatments, such as chemotherapy, are all burdened by a risk of AE-ILD occurrence. Radiotherapy is important for managing both early-stage and advanced lung cancer, but it also poses risks. Stereotactic body radiation and particle beam therapies have varying degrees of safety, with the latter potentially offering a lower risk of AE. Percutaneous ablation techniques can help patients who are not eligible for surgery. However, these procedures may complicate ILD, and their associated risks still need to be fully understood, necessitating further research for improved safety. Overall, while advancements in lung cancer treatment have improved outcomes for many patients, the complexity of managing patients with concomitant ILD needs careful consideration and multidisciplinary assessment. This review provides a detailed evaluation of these risks, emphasizing the need for personalized treatment approaches and monitoring to improve patient outcomes in this challenging population.

Improving Outcomes of CT-Guided Malignant Lung Lesion Microwave Ablation by Tract Sealing Using Venous Blood Clot

Background: Complications, particularly pneumothorax, are common following lung interventions and occasionally necessitate further examinations, extend hospital stays, increase treatment costs, and result in long-term health impairment or even death. A few lung intervention tract sealants have been explored to reduce procedure-related complications. Objectives: The primary objective of this prospective non-randomized study was to assess the complication rates and risk factors for computed tomography-guided lung microwave ablation (MWA) with autologous blood clot as a tract sealant. Methods: Twenty-one patients underwent a total of 26 MWA sessions for lung malignancy followed by injection of the patient's clotted venous blood into the ablation tract while retracting the coaxial needle. Ablation tract sealing was successful in all MWA sessions. Results: Pneumothorax was the only complication observed in five (19.2%) sessions, with one patient (3.8%) requiring chest tube insertion. The male sex was a statistically significant risk factor for pneumothorax (p = 0.042), and patients with lung emphysema had almost fivefold higher odds of developing pneumothorax (OR 4.8; 95% CI, 0.617-37.351; p = 0.281). Conclusions: This study concludes that pneumothorax is the primary complication following lung MWA, and the male sex is a risk factor. Ablation tract sealing with autologous venous blood is a straightforward and inexpensive technique that can reduce the incidence of procedure-related pneumothorax.

Effectiveness of Track Cauterization in Reduction of Adverse Events for Lung Microwave Ablation

PURPOSE

To evaluate the effectiveness of track cautery for lung microwave ablation (MWA) to reduce postprocedural adverse events (AE).

MATERIALS AND METHODS

Patients who underwent percutaneous lung MWA between 2012 and 2021 were divided into 2 cohorts: patients in whom track cautery was conducted during antenna removal and patients in whom the antenna was simply removed. Patient demographics, treatment history, tumor characteristics, and ablation details were collected. Postprocedural AEs including immediate, enlarging, and delayed pneumothorax (PTX), pleural effusion, and reinterventions were recorded. Univariate and multivariate logistic regression models were used to identify factors associated with AEs.

RESULTS

This study included 365 lung MWA sessions for 190 patients. Of the 165 patients in the cautery cohort, 78 (47%) had immediate PTX, 16 (10%) had enlarging PTX, 2 (1%) had delayed PTX, and 15 (9%) needed interventions. Of the 200 patients in the noncautery cohort, 85 (43%) had immediate PTX, 45 (23%) had enlarging PTX, 16 (8%) had delayed PTX, and 37 (19%) needed interventions. The cautery cohort had significantly reduced rates of enlarging PTX (odds ratio [OR], 0.67; 95% CI, 0.34-1.33; P = .002), delayed PTX (OR, 0.15; 95% CI, 0.03-0.89; P = .037), and pleural effusion (OR, 0.38; 95% CI, 0.15-0.99; P = .049). The presence of emphysema, large tumor size, and left lower lobe location were shown to be significant predictors of AEs and the need for interventions (P < .05).

CONCLUSIONS

Track cauterization is associated with reduction of post-MWA enlarging PTX, delayed PTX, and pleural effusion. Presence of emphysema, lack of track cautery, large tumor size, and tumors in the left lower lobe were shown to be predictors of postprocedural AEs.

Advances in Image-Guided Ablation Therapies for Solid Tumors

Image-guided solid tumor ablation methods have significantly advanced in their capability to target primary and metastatic tumors. These techniques involve noninvasive or percutaneous insertion of applicators to induce thermal, electrochemical, or mechanical stress on malignant tissue to cause tissue destruction and apoptosis of the tumor margins. Ablation offers substantially lower risks compared to traditional methods. Benefits include shorter recovery periods, reduced bleeding, and greater preservation of organ parenchyma compared to surgical intervention. Due to the reduced morbidity and mortality, image-guided tumor ablation offers new opportunities for treatment in cancer patients who are not candidates for resection. Currently, image-guided ablation techniques are utilized for treating primary and metastatic tumors in various organs with both curative and palliative intent, including the liver, pancreas, kidneys, thyroid, parathyroid, prostate, lung, breast, bone, and soft tissue. The invention of new equipment and techniques is expanding the criteria of eligible patients for therapy, as now larger and more high-risk tumors near critical structures can be ablated. This article provides an overview of the different imaging modalities, noninvasive, and percutaneous ablation techniques available and discusses their applications and associated complications across various organs.

Safety and efficacy of CT-guided percutaneous microwave ablation for stage I non-small cell lung cancer in patients with comorbid idiopathic pulmonary fibrosis

OBJECTIVES

To evaluate the safety and efficacy of microwave ablation (MWA) for stage I non-small cell lung cancer (NSCLC) in patients with idiopathic pulmonary fibrosis (IPF).

MATERIALS AND METHODS

A retrospective single-center cohort study was conducted in patients with clinical stage I NSCLC who underwent CT-guided MWA from Nov 2016 to Oct 2021. The patients were divided into the IPF group and the non-IPF group. The primary endpoints were 90-day adverse events and hospital length of stay (HLOS). The secondary endpoints included overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 107 patients (27 with IPF and 80 without IPF) were finally included for analysis. No procedure-related acute exacerbation of IPF or death occurred post-MWA. The rates of adverse events were similar between the groups (48.6% vs. 47.7%; p = 0.998). The incidence of grade 3 adverse events in the IPF group was higher than that in the non-IPF group without a significant difference (13.5% vs. 4.6%; p = 0.123). Median HLOS was 5 days in both groups without a significant difference (p = 0.078). The 1-year and 3-year OS were 85.2%/51.6% in the IPF group, and 97.5%/86.4% in the non-IPF group. The survival of patients with IPF was significantly poorer than the survival of patients without IPF (p < 0.001). There was no significant difference for PFS (p = 0.271).

CONCLUSION

MWA was feasible in the treatment of stage I NSCLC in patients with IPF. IPF had an adverse effect on the survival of stage I NSCLC treated with MWA.

CLINICAL RELEVANCE STATEMENT

CT-guided microwave ablation is a well-tolerated and effective potential alternative treatment for stage I non-small cell lung cancer in patients with idiopathic pulmonary fibrosis.

KEY POINTS

• Microwave ablation for stage I non-small cell lung cancer was well-tolerated without procedure-related acute exacerbation of idiopathic pulmonary fibrosis and death in patients with idiopathic pulmonary fibrosis. • No differences were observed in the incidence of adverse events between patients with idiopathic pulmonary fibrosis and those without idiopathic pulmonary fibrosis after microwave ablation (48.6% vs. 47.7%; p = 0.998). • The 1-year and 3-year overall survival rates (85.2%/51.6%) in the idiopathic pulmonary fibrosis group were worse than those in the non- idiopathic pulmonary fibrosis group (97.5%/86.4%) (p < 0.001).

Lung Needle Biopsy and Lung Ablation: Indications, Patient Management, and Postprocedure Imaging Findings

The clinical role and use of percutaneous transthoracic needle biopsy (TTNB) and ablation of lung tumors are evolving. Here we discuss important considerations for referring providers, including current and emerging indications supported by guidelines, critical aspects of pre and postprocedure patient management, and expected postprocedure imaging findings.

[The role of endoscopy in the management of peripheral pulmonary nodules, part 2: Treatment]

The management of peripheral lung nodules is challenging, requiring specialized skills and sophisticated technologies. The diagnosis now appears accessible to advanced endoscopy (see Part 1), which can also guide treatment of these nodules; this second part provides an overview of endoscopy techniques that can enhance surgical treatment through preoperative marking, and stereotactic radiotherapy treatment through fiduciary marker placement. Finally, we will discuss how, in the near future, these advanced endoscopic techniques will help to implement ablation strategy.

Transbronchial Microwave Ablation of Peripheral Lung Tumors: The NAVABLATE Study

BACKGROUND

Image-guided thermal ablation is a minimally invasive local therapy for lung malignancies. NAVABLATE characterized the safety and performance of transbronchial microwave ablation (MWA) in the lung.

METHODS

The prospective, single-arm, 2-center NAVABLATE study (NCT03569111) evaluated transbronchial MWA in patients with histologically confirmed lung malignancies ≤30 mm in maximum diameter who were not candidates for, or who declined, both surgery and stereotactic body radiation therapy. Ablation of 1 nodule was allowed per subject. The nodule was reached with electromagnetic navigation bronchoscopy. Cone-beam computed tomography was used to verify the ablation catheter position and to evaluate the ablation zone postprocedure. The primary end point was composite adverse events related to the transbronchial MWA device through 1-month follow-up. Secondary end points included technical success (nodule reached and ablated according to the study protocol) and technique efficacy (satisfactory ablation based on 1-month follow-up imaging).

RESULTS

Thirty subjects (30 nodules; 66.7% primary lung, 33.3% oligometastatic) were enrolled from February 2019 to September 2020. The pre-procedure median nodule size was 12.5 mm (range 5 to 27 mm). Procedure-day technical success was 100% (30/30), with a mean ablative margin of 9.9±2.7 mm. One-month imaging showed 100% (30/30) technique efficacy. The composite adverse event rate related to the transbronchial MWA device through 1-month follow-up was 3.3% (1 subject, mild hemoptysis). No deaths or pneumothoraces occurred. Four subjects (13.3%) experienced grade 3 complications; none had grade 4 or 5.

CONCLUSION

Transbronchial microwave ablation is an alternative treatment modality for malignant lung nodules ≤30 mm. There were no deaths or pneumothorax. In all, 13.3% of patients developed grade 3 or above complications.

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.

An Interventional Radiologist's Guide to Lung Cancer

Lung cancer continues to be the third leading cause of cancer and the leading cause of cancer deaths. As the field of interventional oncology continues to grow, interventional radiologists are increasingly treating lung cancer patients. Involvement begins with tissue diagnosis for which biomarkers and immunohistochemistry are used to guide selective and advanced medical therapies. An interventional radiologist must be aware of the rationale behind tissue diagnosis and techniques to minimize biopsy complications. Staging is an important part of tumor board conversations and drives treatment pathways. Surgical therapy remains the gold standard for early-stage disease but with an aging population the need for less invasive treatments such as radiation therapy and ablation continue to grow. The interventionalist must be aware of the indications, techniques, and pre- and posttherapy managements for percutaneous ablation. Endovascular therapy is broadly divided into therapeutic treatment of lung cancer, which is gaining traction, and treatment of lung cancer complications such as hemoptysis. This review aims to provide a good basis for interventional radiologists treating lung cancer patients.

Computed tomography-guided microwave ablation for right middle lobe pulmonary nodules: a retrospective, single-center, case-control study

PURPOSE

This retrospective, single-center, case-control study evaluated the safety and efficacy of Computed tomography (CT)-guided microwave ablation (MWA) for pulmonary nodules located in the right middle lobe (RML), a challenging location associated with a high frequency of complications.

METHODS

Between May 2020 and April 2022, 71 patients with 71 RML pulmonary nodules underwent 71 MWA sessions. To comparison, 142 patients with 142 pulmonary nodules in non-RML were selected using propensity score matching. The technical success, technique efficacy, complications, and associated factors were analyzed. The duration of the procedure and post-ablation hospital stay were also recorded.

RESULTS

Technical success was achieved in 100% of all patients. There were no significant differences in technique efficacy rates between the RML and non-RML groups (97.2% vs. 95.1%, p = 0.721). However, both major (47.9% vs. 19.7%, p < 0.001) and minor (26.8% vs. 11.3%, p = 0.004) pneumothorax were more common in the RML group than non-RML group. MWA for RML pulmonary nodules was identified as an independent risk factor for pneumothorax (p < 0.001). The duration of procedures (51.7 min vs. 35.3 min, p < 0.001) and post-ablation hospital stays (4.7 days vs. 2.8 days, p < 0.001) were longer in the RML group than non-RML group.

CONCLUSIONS

CT-guided MWA for RML pulmonary nodules showed comparable efficacy compared with other lobes, but posed a higher risk of pneumothorax complications, necessitating longer MWA procedure times and extended hospital stays.

Ablation of Stage I-II Non-Small Cell Lung Cancer in Patients With Interstitial Lung Disease: A Multicenter Retrospective Study

BACKGROUND. Treatment options for patients with interstitial lung disease (ILD) who develop stage I-II non-small cell lung cancer (NSCLC) are severely limited, given that surgical resection, radiation, and systemic therapy are associated with significant morbidity and mortality. OBJECTIVE. The aim of this study was to evaluate the safety and efficacy of percutaneous ablation of stage I-II NSCLC in patients with ILD. METHODS. This retrospective study included patients with ILD and stage I-II NSCLC treated with percutaneous ablation in three health systems between October 2004 and February 2023. At each site, a single thoracic radiologist, blinded to clinical outcomes, reviewed preprocedural chest CT examinations for the presence and type of ILD according to 2018 criteria proposed by the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Society. The primary outcome was 90-day major (grade ≥ 3) adverse events, based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Secondary outcomes were hospital length of stay (HLOS), local tumor control, and overall survival (OS). RESULTS. The study included 33 patients (19 men, 14 women; median age, 78 years; 16 patients with Eastern Cooperative Oncology Group performance status ≤ 1) with ILD who underwent 42 percutaneous ablation sessions (21 cryoablations, 11 radiofrequency ablations, 10 microwave ablations) of 43 NSCLC tumors ((median tumor size, 1.6 cm; IQR, 1.4-2.5 cm; range, 0.7-5.4 cm; 37 stage I, six stage II). The extent of lung fibrosis was 20% or less in 24 patients; 17 patients had imaging findings of definite or probable usual interstitial pneumonia. The 90-day major adverse event rate was 14% (6/42), including one CTCAE grade 4 event. No acute ILD exacerbation or death occurred within 90 days after ablation. The median HLOS was 1 day (IQR, 0-2 days). Median imaging follow-up for local tumor control was 17 months (IQR, 11-32 months). Median imaging or clinical follow-up for OS was 16 months (IQR, 6-26 months). Local tumor control and OS were 78% and 77%, respectively, at 1 year and 73% and 46% at 2 years. CONCLUSION. Percutaneous ablation appears to be a safe and effective treatment option for stage I-II NSCLC in the setting of ILD after multidisciplinary selection. CLINICAL IMPACT. Patients with ILD and stage I-II NSCLC should be considered for percutaneous ablation given that they are frequently ineligible for surgical resection, radiation, and systemic therapy.

Risk prediction of intraoperative pain in percutaneous microwave ablation of lung tumors under CT guidance

OBJECTIVES

To evaluate the effect of intraoperative pain in microwave ablation of lung tumors (MWALT) on local efficacy and establish the pain risk prediction model.

METHODS

It was a retrospectively study. Consecutive patients with MWALT from September 2017 to December 2020 were divided into mild and severe pain groups. Local efficacy was evaluated by comparing technical success, technical effectiveness, and local progression-free survival (LPFS) in two groups. All cases were randomly allocated into training and validation cohorts at a ratio of 7:3. A nomogram model was established using predictors identified by logistics regression in training dataset. The calibration curves, C-statistic, and decision curve analysis (DCA) were used to evaluate the accuracy, ability, and clinical value of the nomogram.

RESULTS

A total of 263 patients (mild pain group: n = 126; severe pain group: n = 137) were included in the study. Technical success rate and technical effectiveness rate were 100% and 99.2% in the mild pain group and 98.5% and 97.8% in the severe pain group. LPFS rates at 12 and 24 months were 97.6% and 87.6% in the mild pain group and 91.9% and 79.3% in the severe pain group (p = 0.034; HR: 1.90). The nomogram was established based on three predictors: depth of nodule, puncture depth, and multi-antenna. The prediction ability and accuracy were verified by C-statistic and calibration curve. DCA curve suggested the proposed prediction model was clinically useful.

CONCLUSIONS

Severe intraoperative pain in MWALT reduced the local efficacy. An established prediction model could accurately predict severe pain and assist physicians in choosing a suitable anesthesia type.

CLINICAL RELEVANCE STATEMENT

This study firstly provides a prediction model for the risk of severe intraoperative pain in MWALT. Physicians can choose a suitable anesthesia type based on pain risk, in order to improve patients' tolerance as well as local efficacy of MWALT.

KEY POINTS

• The severe intraoperative pain in MWALT reduced the local efficacy. • Predictors of severe intraoperative pain in MWALT were the depth of nodule, puncture depth, and multi-antenna. • The prediction model established in this study can accurately predict the risk of severe pain in MWALT and assist physicians in choosing a suitable anesthesia type.

Microwave Ablation for Inoperable Stage I Non-Small Cell Lung Cancer in Patients Aged ≥70 Years: A Prospective, Single-Center Study

PURPOSE

To evaluate the safety and survival outcomes of computed tomography-guided microwave ablation (MWA) for medically inoperable Stage I non-small cell lung cancer (NSCLC) in patients aged ≥70 years.

MATERIALS AND METHODS

This study was a prospective, single-arm, single-center clinical trial. The MWA clinical trial enrolled patients aged ≥70 years with medically inoperable Stage I NSCLC from January 2021 to October 2021. All patients received biopsy and MWA synchronously with the coaxial technique. The primary endpoints were 1-year overall survival (OS) and progression-free survival (PFS). The secondary endpoint was adverse events.

RESULTS

A total of 103 patients were enrolled. Ninety-seven patients were eligible and analyzed. The median age was 75 years (range, 70-91 years). The median diameter of tumors was 16 mm (range, 6-33 mm). Adenocarcinoma (87.6%) was the most common histologic finding. With a median follow-up of 16.0 months, the 1-year OS and PFS rates were 99.0% and 93.7%, respectively. There were no procedure-related deaths in any patient within 30 days after MWA. Most of the adverse events were minor.

CONCLUSION

MWA is an effective and safe treatment for patients aged ≥70 years with medically inoperable Stage I NSCLC.

Cryoablation and immunity in non-small cell lung cancer: a new era of cryo-immunotherapy

Despite remarkable advances in tumor response and patient survival in the past decade, systemic immunotherapies for lung cancer result in an objective response in only around half of patients treated. On the basis of this limitation, combination strategies are being investigated to improve response rates. Cryoablation has been proposed as one such technique to induce immunogenic cell death and synergize with systemic immunotherapies, including immune checkpoint inhibitors. Cryoablation has been traditionally delivered percutaneously with imaging guidance although recent technological advances allow for bronchoscopic delivery. Herein, we review the pre-clinical and clinical evidence for the use of cryoablation in non-small cell lung cancer and potential induction of anti-tumor immunity. We highlight ongoing studies involving this approach and propose areas of future investigation.

Stereotactic body radiation therapy and thermal ablation for treatment of NSCLC: A systematic literature review and meta-analysis

RATIONALE

Stereotactic body radiation therapy (SBRT) is the standard of care for inoperable early stage non-small cell lung cancer (NSCLC). Use of image guided thermal ablation (IGTA; including microwave ablation [MWA] and radiofrequency ablation [RFA]) has increased in NSCLC, however there are no studies comparing all three.

OBJECTIVE

To compare the efficacy of IGTA (including MWA and RFA) and SBRT for the treatment of NSCLC.

METHODS

Published literature databases were systematically searched for studies assessing MWA, RFA, or SBRT. Local tumor progression (LTP), disease-free survival (DFS), and overall survival (OS) were assessed with single-arm pooled analyses and meta-regressions in NSCLC patients and a stage IA subgroup. Study quality was assessed with a modified methodological index for non-randomized studies (MINORS) tool.

RESULTS

Forty IGTA study-arms (2,691 patients) and 215 SBRT study-arms (54,789 patients) were identified. LTP was lowest after SBRT at one and two years in single-arm pooled analyses (4% and 9% vs. 11% and 18%) and at one year in meta-regressions when compared to IGTA (OR = 0.2, 95%CI = 0.07-0.63). MWA patients had the highest DFS of all treatments in single-arm pooled analyses. In meta-regressions at two and three-years, DFS was significantly lower for RFA compared to MWA (OR = 0.26, 95%CI = 0.12-0.58; OR = 0.33, 95%CI = 0.16-0.66, respectively). OS was similar across modalities, timepoints, and analyses. Older age, male patients, larger tumors, retrospective studies, and non-Asian study region were also predictors of worse clinical outcomes. In high-quality studies (MINORS score ≥ 7), MWA patients had better clinical outcomes than the overall analysis. Stage IA MWA patients had lower LTP, higher OS, and generally lower DFS, compared to the main analysis of all NSCLC patients.

CONCLUSIONS

NSCLC patients had comparable outcomes after SBRT and MWA, which were better than those with RFA.

Outcomes following cryoablation of stage IA non-small cell lung cancer in patients with and without interstitial lung disease: A retrospective single-center cohort study

OBJECTIVE

To compare the safety and efficacy of cryoablation of treatment-naïve stage IA non-small cell lung cancer (NSCLC) in patients with and without interstitial lung disease (ILD).

MATERIALS AND METHODS

This retrospective single-center cohort study evaluated 33 consecutive patients (24 females, median age 75 years, Eastern Cooperative Oncology Group performance score 0-3) with ILD (9 patients) and without ILD (24 patients) who underwent 39 percutaneous cryoablations to treat 42 stage IA (8th IASLC edition) NSCLC measuring 1.2 cm (range 0.5-2.6 cm) from 2018 to 2022. Presence of ILD was determined according to 2018 American Thoracic Society Criteria on pre-ablation CT scans. The primary outcome was 90-day adverse events graded by the Common Terminology Criteria for Adverse Events (CTCAE) v5.0. Secondary outcomes were hospital length of stay (LOS), local recurrence-free survival, overall survival, and the cumulative incidence of local recurrence with death as a competing risk.

RESULTS

Adverse events ranged from grade 1-3 and occurred more often in the non-ILD group (p <.001). No acute exacerbation of ILD or death occurred within 90 days after cryoablation. The median LOS was 1 day (interquartile range 1-2 days) and did not differ between groups. One patient with ILD and two patients without ILD died after 22, 26, and 27 months from causes unrelated to cryoablation. Median imaging follow-up was 11 months (range, 0-47 months) and three tumors (7%) showed local recurrence after 4, 17, and 22 months. No difference in the cumulative incidence of local recurrence (p =.56) was found. Among all patients, local recurrence-free survival on a per-tumor basis and overall survival were 97% and 100% at 1 year, respectively.

CONCLUSION

Adverse events and local recurrence following percutaneous cryoablation of stage IA NSCLC did not differ between patients with and without ILD. No acute exacerbation of ILD or death within 90 days were observed.

Safety and Effectiveness of Percutaneous Image-Guided Thermal Ablation of Juxtacardiac Lung Tumors

PURPOSE

To evaluate the safety and effectiveness of percutaneous image-guided thermal ablation (IGTA) for juxtacardiac lung tumors.

MATERIALS AND METHODS

This bi-institutional retrospective cohort study included 23 consecutive patients (13 [57%] male; mean age, 55 years ± 18) with 30 juxtacardiac lung tumors located ≤10 mm from the pericardium treated in 28 IGTA sessions (25 sessions of cryoablation and 3 sessions of microwave ablation) between April 2008 and August 2022. The primary outcome was any adverse cardiac event within 90 days after ablation. Secondary outcomes included noncardiac adverse events, local tumor progression-free survival (LT-PFS), and the cumulative incidence of local tumor progression with death as a competing risk. Two tumors treated without curative intent or follow-up imaging were considered in the safety analysis but not in the progression analysis.

RESULTS

The median imaging follow-up duration was 22 months (interquartile range [IQR], 10-53 months). Primary technical success was achieved in 25 (89%) ablations. No adverse cardiac events attributable to IGTA occurred. One patient experienced a phrenic nerve injury. The median LT-PFS duration was 59 months (IQR, 32-73 months). At 1, 3, and 5 years, LT-PFS was 90% (95% CI, 78%-100%), 74% (CI, 53%-100%), and 45% (CI, 20%-97%), respectively, and the cumulative incidence of local tumor progression was 4.3% (CI, 0.29%-19%), 11% (CI, 1.6%-30%), and 26% (CI, 3.3%-58%), respectively.

CONCLUSIONS

IGTA is safe and effective for lung tumors located ≤10 mm from the pericardium. No adverse cardiac events were not observed within 90 days after ablation.

Innovative Invasive Loco-Regional Techniques for the Treatment of Lung Cancer

Surgical resection is still the standard treatment for early-stage lung cancer. A multimodal treatment consisting of chemotherapy, radiotherapy and/or immunotherapy is advised for more advanced disease stages (stages IIb, III and IV). The role of surgery in these stages is limited to very specific indications. Regional treatment techniques are being introduced at a high speed because of improved technology and their possible advantages over traditional surgery. This review includes an overview of established and promising innovative invasive loco-regional techniques stratified based on the route of administration, including endobronchial, endovascular and transthoracic routes, a discussion of the results for each method, and an overview of their implementation and effectiveness.

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.

Percutaneous image-guided thermal ablation of lung cancer: What is the evidence?

Thermal ablation techniques have now been used for more than twenty years in the treatment of primary lung tumours, predominantly non-small cell lung cancer (NSCLC). Although primarily used for the treatment of early-stage disease in non-surgical patients, thermal ablation is now also being used in selected patients with oligometastatic and oligoprogressive disease. This review discusses the techniques available for thermal ablation, the evidence for use of thermal ablation in primary lung tumours in early- and advanced-stage disease and compares thermal ablation to alternative treatment strategies.

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.

Diagnosis and Treatment of Lung Cancer in the Setting of Interstitial Lung Disease

Interstitial lung disease (ILD) including idiopathic pulmonary fibrosis increases the risk of developing lung cancer. Diagnosing and staging lung cancer in patients with ILD is challenging and requires careful interpretation of computed tomography (CT) and fluorodeoxyglucose PET/CT to distinguish nodules from areas of fibrosis. Minimally invasive tissue sampling is preferred but may be technically challenging given tumor location, coexistent fibrosis, and pneumothorax risk. Current treatment options include surgery, radiation therapy, percutaneous thermal ablation, and systemic therapy; however, ILD increases the risks associated with each treatment option, especially acute ILD exacerbation.

Safety and efficacy of microwave ablation for lung cancer adjacent to the interlobar fissure

Background

This retrospective study aimed to assess the safety and efficacy of microwave ablation for lung tumors adjacent to the interlobar fissures.

Methods

From May 2020 to April 2021, 59 patients with 66 lung tumors (mean diameter, 16.9 ± 7.7 mm; range, 6–30 mm) adjacent to the interlobar fissures who underwent microwave ablation at our institution were identified and included in this study. Based on the relationship between the tumor and the interlobar fissure, tumors can be categorized into close to the fissure, causing the fissure, and involving the fissure. The complete ablation rate, local progression‐free survival, complications, and associated factors were analyzed.

Results

All 66 histologically proven tumors were treated using computed tomography‐guided microwave ablation. The complete ablation rate was 95.5%. Local progression‐free survival at 3, 6, 9, and 12 months were 89.4%, 83.3%, 74.2%, and 63.6%, respectively. The complications included pneumothorax (34.8%), pleural effusion (24.2%), cavity (18.2%), and pulmonary infection (7.6%). There were statistical differences in the incidence of pneumothorax, cavity, and delayed complications between the groups with and without antenna punctures through the fissure.

Conclusions

Microwave ablation is a safe and effective treatment for lung tumor adjacent to the interlobar fissure. Antenna puncturing though the interlobar fissure may be a potential risk factor for pneumothorax, cavity, and delayed complications.

Image-Guided Percutaneous Ablation for Primary and Metastatic Tumors

Image-guided percutaneous ablation methods have been further developed during the recent two decades and have transformed the minimally invasive and precision features of treatment options targeting primary and metastatic tumors. They work by percutaneously introducing applicators to precisely destroy a tumor and offer much lower risks than conventional methods. There are usually shorter recovery periods, less bleeding, and more preservation of organ parenchyma, expanding the treatment options of patients with cancer who may not be eligible for resection. Image-guided ablation techniques are currently utilized for the treatment of primary and metastatic tumors in various organs including the liver, pancreas, kidneys, thyroid and parathyroid, prostate, lung, bone, and soft tissue. This article provides a brief review of the various imaging modalities and available ablation techniques and discusses their applications and associated complications in various organs.

Microwave Ablation versus Stereotactic Body Radiotherapy for Stage I Non-Small Cell Lung Cancer: A Cost-Effectiveness Analysis

PURPOSE

To assess the cost-effectiveness of microwave ablation (MWA) and SBRT for patients with inoperable stage I non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

A literature search was performed in MEDLINE with broad search clusters. A decision-analysis model was constructed over a 5-year period. The model incorporated treatment-related complications and long-term recurrence. All clinical parameters were derived from the literature with preference to long-term prospective trials. A healthcare payers' perspective was adopted. Outcomes were measured in quality-adjusted life years (QALY) extracted from prior studies and United States dollars from Medicare reimbursements and prior studies. Base case calculations, probabilistic sensitivity analysis with 10,000 Monte Carlo simulations, and multiple one- and two-way sensitivity analyses were performed.

RESULTS

MWA yielded a health benefit of 2.31 QALY at a cost of $195,331, whereas SBRT yielded a health benefit of 2.33 QALY at a cost of $225,271. The incremental cost-effectiveness ratio was $1,480,597/QALY, indicating that MWA is the more cost-effective strategy. The conclusion remains unchanged in probabilistic sensitivity analysis with MWA being the optimal cost strategy in 99.84% simulations. One-way sensitivity analyses revealed that MWA remains cost-effective when its annual recurrence risk is below 18.4% averaged over 5 years, when the SBRT annual recurrence risk is above 1.44% averaged over 5 years, or when MWA is at least $7,500 cheaper than SBRT.

CONCLUSION

Microwave ablation appears to be a more cost-effective than stereotactic body radiotherapy for patients with inoperable stage I non-small cell lung cancer.

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.

Update on Image-Guided Thermal Lung Ablation: Society Guidelines, Therapeutic Alternatives, and Postablation Imaging Findings

Percutaneous image-guided thermal ablation (IGTA) has been endorsed by multiple societies as a safe and effective lung-preserving treatment for primary lung cancer and metastases involving the lung and chest wall. This article reviews the role of IGTA in the care continuum of patients with thoracic neoplasms and discusses strategies to identify the optimal local therapy considering patient and tumor characteristics. The advantages and disadvantages of percutaneous thermal ablation compared to surgical resection and stereotactic body radiotherapy are summarized. Principles of radiofrequency ablation, microwave ablation, and cryoablation, as well as the emerging use of transbronchial thermal ablation, are described. Specific considerations are presented regarding the role of thermal ablation for early-stage non-small cell lung cancer (NSCLC), multifocal primary NSCLC, pulmonary metastases, salvage of recurrent NSCLC after surgery or radiation, and pain palliation for tumors involving the chest wall. Recent changes to professional society guidelines regarding the role of thermal ablation in the lung, including for treatment of oligometastatic disease, are highlighted. Finally, recommendations are provided for imaging follow-up after thermal ablation of lung tumors, accompanied by examples of expected postoperative findings and patterns of disease recurrence.

A CT-Based Radiomics Nomogram to Predict Complete Ablation of Pulmonary Malignancy: A Multicenter Study

Objective

Thermal ablation is a minimally invasive procedure for the treatment of pulmonary malignancy, but the intraoperative measure of complete ablation of the tumor is mainly based on the subjective judgment of clinicians without quantitative criteria. This study aimed to develop and validate an intraoperative computed tomography (CT)-based radiomic nomogram to predict complete ablation of pulmonary malignancy.

Methods

This study enrolled 104 individual lesions from 92 patients with primary or metastatic pulmonary malignancies, which were randomly divided into training cohort (n=74) and verification cohort (n=30). Radiomics features were extracted from the original CT images when the study clinicians determined the completion of the ablation surgery. Minimum redundancy maximum relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) were adopted for the dimensionality reduction of high-dimensional data and feature selection. The prediction model was developed based on the radiomics signature combined with the independent clinical predictors by multiple logistic regression analysis. The area under the curve (AUC), accuracy, sensitivity, and specificity were calculated. Receiver operating characteristic (ROC) curves and calibration curves were used to evaluate the predictive performance of the model. Decision curve analysis (DCA) was applied to estimate the clinical usefulness and net benefit of the nomogram for decision making.

Results

Thirteen CT features were selected to construct radiomics prediction model, which exhibits good predictive performance for determination of complete ablation of pulmonary malignancy. The AUCs of a CT-based radiomics nomogram that integrated the radiomics signature and the clinical predictors were 0.88 (95% CI 0.80-0.96) in the training cohort and 0.87 (95% CI: 0.71–1.00) in the validation cohort, respectively. The radiomics nomogram was well calibrated in both the training and validation cohorts, and it was highly consistent with complete tumor ablation. DCA indicated that the nomogram was clinically useful.

Conclusion

A CT-based radiomics nomogram has good predictive value for determination of complete ablation of pulmonary malignancy intraoperatively, which can assist in decision-making.

Cryoablation in Locoregional Management of Complex Unresectable Chest Neoplasms

RATIONALE AND OBJECTIVES

The aim of our retrospective study was to assess the safety and feasibility of cryoablation in high-risk patients with complex chest neoplastic lesions.

MATERIALS AND METHODS

Twenty patients with complex chest malignancies, both primary and secondary, located in the mediastinum, lung, and chest wall, underwent percutaneous CT-guided cryoablation treatments. Procedural success as well as complications were evaluated.

RESULTS

A total of 24 neoplastic lesions were treated (mean diameter: 27 mm; range: 7-54 mm). Technical success was obtained in all patients, without major complications or intraprocedural death. A pneumothorax not requiring a drainage tube placement was registered in 50% of patients, while 3/24 patients had a grade 3 pneumothorax requiring a chest tube placement.

CONCLUSION

Percutaneous CT-guided cryoablation seems a safe and feasible treatment for complex thoracic lesions.

Society of Interventional Radiology Multidisciplinary Position Statement on Percutaneous Ablation of Non-small Cell Lung Cancer and Metastatic Disease to the Lungs: Endorsed by the Canadian Association for Interventional Radiology, the Cardiovascular and Interventional Radiological Society of Europe, and the Society of Interventional Oncology

PURPOSE

To state the Society of Interventional Radiology's position on the use of image-guided thermal ablation for the treatment of early stage non-small cell lung cancer, recurrent lung cancer, and metastatic disease to the lung.

MATERIALS AND METHODS

A multidisciplinary writing group, with expertise in treating lung cancer, conducted a comprehensive literature search to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements.

RESULTS

A total of 63 studies, including existing systematic reviews and meta-analysis, retrospective cohort studies, and single-arm trials were identified. The expert writing group developed and agreed on 7 recommendations on the use of image-guided thermal ablation in the lung.

CONCLUSION

SIR considers image-guided thermal ablation to be an acceptable treatment option for patients with inoperable Stage I NSCLC, those with recurrent NSCLC, as well as patients with metastatic lung disease.

Artificial pneumothorax improves radiofrequency ablation of pulmonary metastases of hepatocellular carcinoma close to mediastinum

Background

To investigate the feasibility, safety and efficacy of percutaneous radiofrequency ablation (RFA) of pulmonary metastases from hepatocellular carcinoma (HCC) contiguous with the mediastinum using the artificial pneumothorax technique.

Method

A total of 40 lesions in 32 patients with pulmonary metastases from HCC contiguous with the mediastinum accepted RFA treatment from August 2014 to May 2018 via the artificial pneumothorax technique. After ablation, clinical outcomes were followed up by contrast enhanced CT. Technical success, local tumor progression (LTP), intrapulmonary distant recurrence (IDR), and adverse events were evaluated. Overall survival (OS) and local tumor progression free survival (LTPFS) were recorded for each patient.

Results

The tumor size was 1.4 ± 0.6 cm in diameter. RFA procedures were all successfully performed without intra-ablative complications. Technical success was noted in 100% of the patients. Five cases of LTP and 8 cases of IDR occurred following the secondary RFA for treatment. Slight pain was reported in all patients. No major complications were observed. The 1, 2, and 3-year LTPFS rates were 90.6, 81.2, and 71.8%, and the 1, 2, and 3-year OS rates were 100, 100 and 87.5%, respectively.

Conclusion

Artificial pneumothorax adjuvant RFA is a feasible, safe, and efficient method for treatment of pulmonary metastases from HCC contiguous with the mediastinum.

Is There a Role for Percutaneous Ablation for Early Stage Lung Cancer? What Is the Evidence?

PURPOSE OF REVIEW

For patients with early stage non-small-cell lung cancer (NSCLC), thermal ablation (TA) has become in the least two decades an option of treatment used worldwide for patients with comorbidities who are not surgical candidates. Here, we review data published with different TA techniques: radiofrequency ablation (RFA), microwave ablation (MWA) and cryoablation. This paper reviews also the comparison that has been made between TA and stereotactic radiotherapy (SBRT).

RECENT FINDINGS

A majority of retrospective studies, the absence of comparative studies, and the variety of techniques make difficult to get evident data. Nevertheless, these stand-alone techniques have demonstrated local efficacy for tumors less than 3 cm and good tolerance on fragile patients. Many recent reviews and database analyses show that outcomes after TA (mainly RFA and MWA) are comparable to SBRT in terms of survival rates. For patients who are unfit for surgery, TA has demonstrated interesting results for safety, benefits in overall survival, and acceptable local control.

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

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

Lung radiofrequency ablation: post-procedure imaging patterns and late follow-up

•

RFA is an effective minimally invasive treatment for selected patients with primary and secondary lung tumors.

•

We described the expected imaging features after RFA of lung tumors, and their frequency over time after the procedure.

•

Radiologists should be familiar with these features in order to avoid misinterpretation and inadequate treatments.

•

These normal post-procedure imaging features must be considered in future post-ablation follow-up protocols.

Purpose

To describe expected imaging features on chest computed tomography (CT) after percutaneous radiofrequency ablation (RFA) of lung tumors, and their frequency over time after the procedure.

Methods

In this double-center retrospective study, we reviewed CT scans from patients who underwent RFA for primary or secondary lung tumors. Patients with partial ablation or tumor recurrence during the imaging follow-up were not included. The imaging features were assessed in pre-defined time points: immediate post-procedure, ≤4 weeks, 5−24 weeks, 25−52 weeks and ≥52 weeks. Late follow-up (3 and 5 years after procedure) was assessed clinically in 48 patients.

Results

The study population consisted of 69 patients and 144 pulmonary tumors. Six out of 69 (9%) patients had primary lung nodules (stage I) and 63/69 (91 %) had metastatic pulmonary nodules. In a patient-level analysis, immediately after lung RFA, the most common CT features were ground glass opacities (66/69, 96 %), consolidation (56/69, 81 %), and hyperdensity within the nodule (47/69, 68 %). Less than 4 weeks, ground glass opacities (including reversed halo sign) was demonstrated in 20/22 (91 %) patients, while consolidation and pleural thickening were detected in 17/22 patients (77 %). Cavitation, pneumatocele, pneumothorax and pleural effusions were less common features. From 5 weeks onwards, the most common imaging features were parenchymal bands.

Conclusions

Our study demonstrated the expected CT features after lung RFA, a safe and effective minimally invasive treatment for selected patients with primary and secondary lung tumors. Diagnostic and interventional radiologists should be familiar with the expected imaging features immediately after RFA and their change over time in order to avoid misinterpretation and inadequate treatments.

Treatment of Post-Ablation Bronchopleural Fistula Using Percutaneous Synthetic Hydrogel Surgical Sealant: Initial Experience of Safety and Efficacy

Purpose Bronchopleural fistula is a rare but serious complication of lung ablation, as it is difficult to treat and is associated with a high mortality rate. Standard therapy often relies on surgical pleurodesis, which can be particularly problematic in patients with poor baseline lung function. A minimally invasive treatment option for bronchopleural fistula may offer an alternative to surgery for appropriate patients. This case series describes the technique, safety and efficacy of percutaneously administered synthetic hydrogel surgical sealant in the treatment of post-ablation bronchopleural fistula in five patients. Materials and methods Retrospective chart review was carried out in five consecutive patients identified to have had BPF after lung ablation between 2009 and 2017 who were treated with percutaneous administration of synthetic hydrogel surgical sealant using CT guidance. Results The procedure was successfully carried out in all patients without immediate complications, and complete resolution of air leak was achieved in four of five patients (80%). Up to the most recent follow-up, no evidence of delayed complications or recurrent air leak was present (follow-up range 1 week-8 years). Conclusion The authors' initial experience shows that targeted surgical sealant is a potentially safe and effective alternative treatment of post-ablation persistent air leak.

Image guided thermal ablation in lung cancer treatment

Lung ablation has been introduced into lung cancer treatment for about two decades. Currently, 3 main choices of thermal energy for lung ablation are radiofrequency ablation (RFA), microwave ablation (MWA), and cryoablation. As a mostly palliative, occasionally curative intent local treatment, the feasibility and safety of lung ablation have been validated in small size lung cancer treatment, especially in lung tumor ≤3 cm. Improved techniques and experience in recent years help render outcomes much better than before for lung cancer patients who are medically inoperable with early stage primary lung cancer, and patients with oligometastasis or local recurrence. For stage IA non-small cell lung cancer (NSCLC) patients underwent RFA, 1- and 2-year overall survival rate were reported as 86.3% and 69.8%. And 1- and 2-year local recurrence rate were reported as 68.9% and 59.8%. Limitations, including heat sink, skin burn, and inconsistent heat conduction, are observed in the first applied ablation technique, RFA. MWA and cryoablation are developed to overcome these limitations and achieve the goal of less morbidity. Generally, imaged guided thermal ablation has a good safety profile, with pneumothorax as the most common morbidity. This article will mainly discuss the current features and application of these ablation techniques in lung cancer treatment.

Standardizing percutaneous Microwave Ablation in the treatment of Lung Tumors: a prospective multicenter trial (MALT study)

OBJECTIVES

To prospectively assess reproducibility, safety, and efficacy of microwave ablation (MWA) in the treatment of unresectable primary and secondary pulmonary tumors.

METHODS

Patients with unresectable primary and metastatic lung tumors up to 4 cm were enrolled in a multicenter prospective clinical trial and underwent CT-guided MWA. Treatments were delivered using pre-defined MW power and duration settings, based on target tumor size and histology classifications. Patients were followed for up to 24 months. Treatment safety, efficacy, and reproducibility were assessed. Ablation volumes were measured at CT scan and compared with ablation volumes obtained on ex vivo bovine liver using equal treatment settings.

RESULTS

From September 2015 to September 2017, 69 MWAs were performed in 54 patients, achieving technical success in all cases and treatment completion without deviations from the standardized protocol in 61 procedures (88.4%). Immediate post-MWA CT scans showed ablation dimensions smaller by about 25% than in the ex vivo model; however, a remarkable volumetric increase (40%) of the treated area was observed at 1 month post-ablation. No treatment-related deaths nor complications were recorded. Treatments of equal power and duration yielded fairly reproducible ablation dimensions at 48-h post-MWA scans. In comparison with the ex vivo liver model, in vivo ablation sizes were systematically smaller, by about 25%. Overall LPR was 24.7%, with an average TLP of 8.1 months. OS rates at 12 and 24 months were 98.0% and 71.3%, respectively.

CONCLUSIONS

Percutaneous CT-guided MWA is a reproducible, safe, and effective treatment for malignant lung tumors up to 4 cm in size.

KEY POINTS

• Percutaneous MWA treatment of primary and secondary lung tumors is a repeatable, safe, and effective therapeutic option. • It provides a fairly reproducible performance on both the long and short axis of the ablation zone. • When using pre-defined treatment duration and power settings according to tumor histology and size, LPR does not increase with increasing tumor size (up to 4 cm) for both primary and metastatic tumors.

Microwave ablation: How we do it?

Minimally invasive techniques such as Image guided thermal ablation are now widely used in the treatment of tumors. Microwave ablation (MWA) is one of the newer modality of thermal ablation and has proven its safety and efficacy in the management of the tumors amenable for ablation for primary and metastatic diseases. It is used in the treatment of primary and secondary liver malignancies, primary and secondary lung malignancies, renal and adrenal tumors and bone metastases. We wanted to share our initial experience with this newer modality. In this article we will describe the mechanism and technique of MWA, comparison done with RFA, advantages and disadvantages of MWA along with pre procedure workup, post procedure follow-up and review of literature.

Bronchoscopic treatments for early-stage peripheral lung cancer: Are we ready for prime time?

Lung cancer is the leading cause of cancer-related death worldwide and surgical lobectomy remains the preferred therapy for patients with early-stage NSCLC. Medical comorbidities and advanced age preclude resection in many patients and minimally invasive ablative therapies are needed for treatment. Stereotactic ablative radiation is established as an effective modality in this patient group, although may be contraindicated in some patients with prior radiation exposure, comorbidities or centrally positioned tumours. Percutaneous ablative methods are available, although are frequently associated with significant complications. Numerous endoscopic ablative techniques are under evaluation. With a more favourable safety profile and the ability to provide diagnosis and staging information potentially within a single procedure, there is a strong rationale for development of bronchoscopic ablative modalities. In the following article, the authors aim to explore the role bronchoscopic ablation may play in treatment of peripheral lung tumours, and to describe a pathway to establishing these modalities as part of routine care. The current status of several bronchoscopic ablative options is discussed in detail.

Cardiac synchronization and arrhythmia during irreversible electroporation

BACKGROUND AND OBJECTIVES

Irreversible electroporation (IRE) is a nonthermal electrical tumor ablative strategy for unresectable tumors. IRE is relatively safe around critical structures but may induce cardiac arrhythmia when its delivery is not synchronized to the cardiac cycle. We performed a systematic literature review to determine rates of arrhythmia when IRE was utilized with or without cardiac synchronization.

METHODS

An online literature search was conducted with additional hand selection of articles. Data were extracted and pooled analyses were performed.

RESULTS

Twelve articles were included in analysis. IRE was performed for 481 patients; 46% hepatic tumors (n = 223), 36% pancreatic lesions (n = 168), and multiple other locations including prostate. Synchronization was performed on 422 patients. Arrhythmias were noted in 3.7% of cases (n = 18/481); cardiac synchronization: 1.2% (n = 5/422) vs unsynchronized: 22.0% (n = 13/59), P < .0001. These events occurred in every organ except the prostate.

CONCLUSIONS

IRE remains a potent technology for unresectable tumors, but arrhythmia is a clinical concern. This literature review confirms that cardiac gating should be used in all cases outside of prostate to prevent this potentially serious adverse event.

RFA of primary and metastatic lung tumors: long-term results

The aim of our study is a retrospective evaluation of effectiveness and safety of Computed Tomography (CT)-guided radiofrequency ablation (RFA) therapy of primary and metastatic lung lesions in patients that cannot be considered surgical candidates. From February 2007 to September 2017, we performed 264 CT-guided ablation sessions on 264 lesions in 174 patients (112 M and 62 F; mean age, 68 years; range 36-83 years) affected by primary and metastatic lung lesions. The 45% of patients was affected by primary lung cancer, with size range lesion of 10-50 mm, and the 55% by metastatic lung lesions with size range of 5-49 mm. All patients had no more than three metastases in the lung and pulmonary relapses were treated up to three times. Overall Survival (OS), Progression-Free Survival (PFS), Local Progression-Free Survival (LPFS) and Cancer-specific survival (CSS) at 1, 3 and 5 years were calculated both in primary lung tumors and in metastatic patients. Immediate and late RFA-related complications were reported. Pulmonary function tests were evaluated after the procedures. The effectiveness of RFA treatment was evaluated by contrast-enhanced CT. In patients affected by primary lung lesions, the OS rates were 66.73% at 1 year, 23.13% at 3 years and 16.19% at 5 years. In patients affected by metastatic lung lesions, the OS rates were 85.11%, 48.86% and 43.33%, respectively, at 1, 3 and 5 years. PFS at 1, 3 and 5 years were 79.8%, 60.42%, 15.4% in primary lung tumors and 78.59%, 51.8% and 6.07% in metastatic patients. LPFS at 1, 3 and 5 years were 79.8%, 64.69%, 18.87% in primary lung tumors and 86.29%, 69.15% and 44.45% in metastatic patients. CSS at 1, 3 and 5 years was 95.56%, 71.84%, 56.72% in primary lung tumors and 94.07%, 71% and 71% in metastatic patients. Immediate RFA-related complications (pneumothorax, pleural effusion and subcutaneous emphysema) were observed, respectively, in 42, 53 and 13 of 264 procedures (15.9%, 20% and 5%). There also occurred one major complication (lung abscess, 0.36%). No significant worsening of pulmonary function was noted. Our retrospective evaluation showed long-term effectiveness, safety and imaging features of CT-guided RFA in patients affected by primary and metastatic lung cancer as an alternative therapy in non-surgical candidates.

Radiofrequency Ablation for Stage I Non-Small Cell Lung Cancer: An Updated Review of Literature from the Last Decade

This review summarizes the current findings on radiofrequency ablation (RFA) for stage I non-small cell lung cancer (NSCLC) from relevant literature published in the last decade. While most earlier studies included small populations and had short follow-up periods, more robust data have become available owing to prospective or large cohort studies. The reported overall survival rates after RFA for stage I NSCLC were 83-96%, 40-74%, and 23-61% at 1, 3, and 5 years, respectively, in recent studies. Furthermore, many comparative studies on the outcomes of RFA and stereotactic body radiotherapy have been performed. Most of these studies report no significant difference in survival outcomes between the therapies. Currently, major guidelines define RFA as a reasonable alternative treatment for stage I NSCLC in non-surgical candidates.

Radiofrequency Ablation, Where It Stands in Interventional Radiology Today

Radiofrequency ablation (RFA) is one of the first developed minimally invasive definitive cancer therapies. The safety and efficacy of RFA is well documented and has led to its incorporation into multiple international societal guidelines. By expanding on the body of knowledge acquired during the clinical use of RFA, alternative ablative technologies have emerged and are successfully competing for locoregional therapy market share. The adaption of newer ablative technologies is leading to a rapid decline in the utilization of RFA by interventional radiologists despite the lack of proven superiority. In their 2010 article, Hong and Georgiades stated "… RFA is likely to remain the mainstay of ablations for small tumors until sufficient experience emerges for the widespread acceptance for alternative ablative modalities." Within a decade of this publication, has this time arrived?