Thermal ablation matches sublobar resection outcomes in older patients with early-stage non-small cell lung cancer

Lung imaging methods: indications, strengths and limitations

Imaging methods are fundamental tools to detect and diagnose lung diseases, monitor their treatment and detect possible complications. Each modality, starting from classical chest radiographs and computed tomography, as well as the ever more popular and easily available thoracic ultrasound, magnetic resonance imaging and nuclear medicine methods, and new techniques such as photon counting computed tomography, radiomics and application of artificial intelligence, has its strong and weak points, which we should be familiar with to properly choose between the methods and interpret their results. In this review, we present the indications, strengths and main limitations of methods for chest imaging.

Value of interventional radiology and their contributions to modern medical systems

Interventional radiology (IR) is a unique specialty that incorporates a diverse set of skills ranging from imaging, procedures, consultation, and patient management. Understanding how IR generates value to the healthcare system is important to review from various perspectives. IR specialists need to understand how to meet demands from various stakeholders to expand their practice improving patient care. Thus, this review discusses the domains of value contributed to medical systems and outlines the parameters of success. IR benefits five distinct parties: patients, practitioners, payers, employers, and innovators. Value to patients and providers is delivered through a wide set of diagnostic and therapeutic interventions. Payers and hospital systems financially benefit from the reduced cost in medical management secondary to fast patient recovery, outpatient procedures, fewer complications, and the prestige of offering diverse expertise for complex patients. Lastly, IR is a field of rapid innovation implementing new procedural technology and techniques. Overall, IR must actively advocate for further growth and influence in the medical field as their value continues to expand in multiple domains. Despite being a nascent specialty, IR has become indispensable to modern medical practice.

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.

Radiofrequency ablation for stage <IIB non-small cell lung cancer: Opportunities, challenges, and the road ahead

Pulmonary carcinoma represents the second common cancer for human race while its mortality rate ranked the first all over the world. Surgery remains the primary option for early-stage non-small cell lung cancer (NSCLC) in some surgical traditions. Nevertheless, only less than half of patients are operable subjected to the limited lung function and multiple primary/metastatic lesions. Recent improvements in minimally invasive surgical techniques have made the procedure accessible to more patients, but this percentage still does not exceed half. In recent years, radiofrequency ablation (RFA), one of the thermal ablation procedures, has gradually advanced in the treatment of lung cancer in addition to being utilized to treat breast and liver cancer. Several guidelines, including the American College of Chest Physicians (ACCP), include RFA as an option for some patients with NSCLC although the level of evidence is mostly limited to retrospective studies. In this review, we emphasize the use of the RFA technique in patients with early-stage NSCLC and provide an overview of the RFA indication population, prognosis status, and complications. Meanwhile, the advantages and disadvantages of RFA proposed in existing studies are compared with surgical treatment and radiotherapy. Due to the high rate of gene mutation and immunocompetence in NSCLC, there are considerable challenges to clinical translation of combining targeted drugs or immunotherapy with RFA that the field has only recently begun to fully appreciate.

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.

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.

Safety and Efficacy Outcomes From a Single-Center Study of Image-Guided Percutaneous Microwave Ablation for Primary and Metastatic Lung Malignancy

Introduction

Image-guided percutaneous microwave ablation (MWA) is becoming a more common treatment option for patients with primary and metastatic lung malignancies. Nevertheless, there is limited literature on the safety and efficacy of MWA compared with standard-of-care therapy, including surgical resection and radiation. This study will report the long-term outcomes after MWA for pulmonary malignancies and investigate the factors related to efficacy, including lesion size, location, and ablation power.

Methods

Retrospective single-center study analyzing 93 patients who underwent percutaneous MWA for primary or metastatic lung malignancies. Outcomes included immediate technical success, local tumor recurrence, overall survival, disease-specific survival, and complications.

Results

At a single institution, 190 lesions (81 primary and 109 metastatic) were treated in 93 patients. Immediate technical success was achieved in all cases. Freedom from local recurrence was 87.6%, 75.3%, and 69.2% and overall survival was 87.7%, 76.2%, and 74.3% at 1 year, 2 years, and 3 years, respectively. Disease-specific survival was 92.6%, 81.8%, and 81.8%. The most common complication was pneumothorax, which occurred in 54.7% (104 of 190) of procedures, with 35.2% (67 of 190) requiring a chest tube. No life-threatening complications occurred.

Conclusions

Percutaneous MWA seems safe and effective for treatment of primary and metastatic lung malignancies and should be considered for patients with limited metastatic burden and lesions less than 3 cm in size.

Management of Lung Cancer in the Patient with Interstitial Lung Disease

Patients with interstitial lung disease (ILD), especially those with pulmonary fibrosis, are at increased risk of developing lung cancer. Management of lung cancer in patients with ILD is particularly challenging. Diagnosis can be complicated by difficulty differentiating lung nodules from areas of focal fibrosis, and percutaneous biopsy approaches confer an increased risk of complications in those with pulmonary fibrosis. Lung cancer treatment in these patients pose several specific considerations. The degree of lung function impairment may preclude lobectomy or surgical resection of any type. Surgical resection can trigger an acute exacerbation of the underlying ILD. The presence of ILD confers an increased risk of pneumonitis with radiotherapy, and many of the systemic therapies also carry an increased risk of pneumonitis in this population. The safety of immunotherapy in the setting of ILD remains to be fully elucidated and concerns remain as to triggering pneumonitis. The purpose of this review is to summarize the evidence regarding consideration for tissue diagnosis, chemotherapy and immunotherapy, radiotherapy, and surgery, in this patient population and discuss emerging areas of research. We also propose a multidisciplinary approach and practical considerations for monitoring for ILD progression during lung cancer treatment.

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.

A guide for managing patients with stage I NSCLC: deciding between lobectomy, segmentectomy, wedge, SBRT and ablation-part 4: systematic review of evidence involving SBRT and ablation

Background

Clinical decision-making for patients with stage I lung cancer is complex. It involves multiple options [lobectomy, segmentectomy, wedge, stereotactic body radiotherapy (SBRT), thermal ablation], weighing multiple outcomes (e.g., short-, intermediate-, long-term) and multiple aspects of each (e.g., magnitude of a difference, the degree of confidence in the evidence, and the applicability to the patient and setting at hand). A structure is needed to summarize the relevant evidence for an individual patient and to identify which outcomes have the greatest impact on the decision-making.

Methods

A PubMed systematic review from 2000-2021 of outcomes after SBRT or thermal ablation vs. resection is the focus of this paper. Evidence was abstracted from randomized trials and non-randomized comparisons with at least some adjustment for confounders. The analysis involved careful assessment, including characteristics of patients, settings, residual confounding etc. to expose degrees of uncertainty and applicability to individual patients. Evidence is summarized that provides an at-a-glance overall impression as well as the ability to delve into layers of details of the patients, settings and treatments involved.

Results

Short-term outcomes are meaningfully better after SBRT than resection. SBRT doesn't affect quality-of-life (QOL), on average pulmonary function is not altered, but a minority of patients may experience gradual late toxicity. Adjusted non-randomized comparisons demonstrate a clinically relevant detriment in long-term outcomes after SBRT vs. surgery. The short-term benefits of SBRT over surgery are accentuated with increasing age and compromised patients, but the long-term detriment remains. Ablation is associated with a higher rate of complications than SBRT, but there is little intermediate-term impact on quality-of-life or pulmonary function tests. Adjusted comparisons show a meaningful detriment in long-term outcomes after ablation vs. surgery; there is less difference between ablation and SBRT.

Conclusions

A systematic, comprehensive summary of evidence regarding Stereotactic Body Radiotherapy or thermal ablation vs. resection with attention to aspects of applicability, uncertainty and effect modifiers provides a foundation for a framework for individualized decision-making.

Survival outcomes of radiofrequency ablation compared with surgery in patients with early-stage primary non-small-cell lung cancer: A meta-analysis

BACKGROUND

This study compared the overall survival (OS) of patients with early-stage primary non-small-cell lung cancer (NSCLC) treated with radiofrequency ablation (RFA) versus surgery.

METHODS

A systematic search was performed in MEDLINE, Embase, Cochrane Central Register, and all available Chinese databases to identify relevant publications from inception to April 2019. This meta-analysis compared hazard ratios (HRs) for OS. A multivariate fixed effects model was used to perform a meta-analysis to compare survival between treatments.

RESULTS

Six retrospective studies were included in the quantitative synthesis. Compared with surgery, RFA was associated with a similar long-term OS. The HRs and 95% confidence intervals (CIs) for 2-, 3- and 5-year OS were 1.74 [0.82, 3.71], 1.15 [0.65, 2.02] and 2.69 [0.41, 17.47], respectively, while those of the pooled data were 1.47 [0.94, 2.32] in patients with early-stage primary NSCLC.

CONCLUSIONS

RFA did not differ significantly from surgery in terms of the 5-year OS in patients with early-stage primary NSCLC. Randomized, controlled clinical trials are warranted to compare these two treatments.

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.

Survival benefit of thermal ablation combined with chemotherapy for the treatment of stage IV nonsmall cell lung cancer: a propensity-matched analysis

OBJECTIVE

To investigate the survival benefit of thermal ablation (TA) plus chemotherapy for Stage-IV nonsmall cell lung cancer (NSCLC).

METHODS

From the Surveillance, Epidemiology and End Results (SEER) database, data of Stage-IV NSCLC patients receiving different treatment modalities (TA plus chemotherapy vs. chemotherapy) from 2004 to 2016 were retrospectively analyzed using propensity-score matching (PSM) for covariates. Kaplan-Meier curves and the log-rank test for intergroup comparison of overall survival (OS) and lung cancer-specific survival (LCSS) and subgroup analyses in the PSM cohort evaluated possible survival benefits. Cox proportional risk models evaluated independent prognostic factors.

RESULTS

Among 52,574 patients, 152 received TA plus chemotherapy. After PSM, the TA plus chemotherapy and chemotherapy groups included 150 and 445 patients, respectively. Compared to the chemotherapy group, the TA plus chemotherapy group had better OS (p = 0.042) and LCSS (p = 0.031), especially in patients aged 70 and older in age-stratified subgroup analysis; no statistically significant beneficial trend was noted for patients younger than 70 years. Subgroup analysis by tumor size showed superior OS and LCSS with TA plus chemotherapy than chemotherapy for tumors ≤3.0 cm; however, no significant difference was found in subgroups with larger tumors. Multivariate analysis showed that TA plus chemotherapy was an independent prognostic factor for OS and LCSS (hazard ratio 0.70 [95% confidence interval 0.59-0.84] and 0.70 [0.58-0.84], respectively; p < 0.001).

CONCLUSION

TA plus chemotherapy is a potential treatment option for Stage-IV NSCLC, especially for patients aged 70 or older with tumor size ≤3 cm.

Sublobar resection versus ablation for stage I non-small-cell lung cancer: a meta-analysis

Background

Stage I non-small-cell lung cancer (NSCLC) can be treated by both ablation and sublobar resection (SR). This meta-analysis was therefore designed to better compare the relative safety and efficacy of these two approaches to treating stage I NSCLC.

Materials and methods

Relevant studies published through November 2020 in the Cochrane Library, Embase, and PubMed databases were identified for analyses which were conducted with RevMan v5.3.

Results

In total, 816 potentially relevant articles were identified, of which 8 were ultimately included in the final meta-analysis. Patients in the SR group exhibited a signficantly lower pooled local recurrence (LR) rate (5.0% vs. 25.4%, P < 0.0001), although pooled distant recurrence (DR) rates were similar in both groups (25.7% vs. 23.1%, P = 0.75). The pooled hazard ratio (HR) for overall survival (OS) (HR: 1.23; 95% CI: 1.13–1.33, P < 0.00001), progression-free survival (PFS) (HR: 1.34; 95% CI: 1.15–1.55, P = 0.0002), and cancer-specific survival (HR: 1.39; 95% CI: 1.15–1.70, P = 0.0009) all indicated better survival outcomes among patients that underwent HR treatment, while pooled complication rates were similar in both groups (27.7% vs. 43.8%, P = 0.27). Patients that underwent ablation exhibited significantly shorter pooled post-operative hospitalization relative to those in the SR group (MD: 5.93; 95% CI: 0.78–11.07, P = 0.02). No evidence of publication bias was detected through funnel plot analyses.

Conclusions

SR treatment of stage I NSCLC patients was associated with a lower LR rate and longer survival as compared to ablation.

National Utilization, Survival, and Costs Analysis of Treatment Options for Stage I Non-Small Cell Lung Cancer: A SEER-Medicare Database Analysis

RATIONALE AND OBJECTIVES

To compare utilization, outcomes, and costs of surgery, radiation therapy, and percutaneous ablation for the treatment of stage I non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Using 2006-2016 Medicare-linked Surveillance, Epidemiology, and End Results (SEER) databases, stage I NSCLC patients who underwent surgery, radiotherapy, or percutaneous ablation were identified using relevant billing codes. National utilization rates were determined. Overall survival for treatment arms were compared using log-rank test and Cox-proportional hazard modeling. Mean direct costs for each treatment strategy during the first year after diagnosis were compared using Analysis of Variance.

RESULTS

A total of 15,847 Stage I NSCLC patients were identified; mean age at diagnosis was 75.5 years (minimum age = 66 years) and 59.2% were female. A total of 10,732 patients (67.7%) underwent only surgery, 5013 (31.6%) only radiotherapy, and 102 (0.6%) only ablation. Utilization of surgery and ablation decreased while radiotherapy utilization increased from 2007 to 2015 (p < 0.0001). Compared to the ablation group, overall survival was greater for the surgery group (HR: 0.7, 95% CI of HR: 0.6-0.9, p = 0.0047) and lower for the radiotherapy group (HR: 1.4, 95% CI of HR: 1.1-1.8, p = 0.002). The mean first year cost of therapy for ablation = $11,976) was significantly less (p < 0.05) than for radiotherapy ($15,447) and surgery ($22,669).

CONCLUSION

In Medicare patients with stage I NSCLC, the utilization of radiation therapy has increased and surgery has declined, while utilization of percutaneous ablation has remained uniformly low. Although overall survival is best for surgery, then ablation, and then radiation therapy, first year treatment costs are lowest for ablation.

Current Management of Oligometastatic Lung Cancer and Future Perspectives: Results of Thermal Ablation as a Local Ablative Therapy

A growing body of evidence shows improved overall survival and progression-free survival after thermal ablation in non-small cell lung carcinoma (NSCLC) patients with a limited number of metastases, combined with chemotherapy or tyrosine kinase inhibitors or after local recurrence. Radiofrequency ablation and microwave ablation are the most evaluated modalities, and target tumor size <3 cm (and preferably <2 cm) is a key factor of technical success and efficacy. Although thermal ablation offers some advantages over surgery and radiotherapy in terms of repeatability, safety, and quality of life, optimal management of these patients requires a multidisciplinary approach, and further randomized controlled trials are required to help refine patient selection criteria. In this article, we present a comprehensive review of available thermal ablation modalities and recent results supporting their use in oligometastatic and oligoprogressive NSCLC disease along with their potential future implications in the emerging field of immunotherapy.

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.

Society of Interventional Radiology Quality Improvement Standards on Percutaneous Ablation of Non-Small Cell Lung Cancer and Metastatic Disease to the Lungs

PURPOSE

To provide guidance on quality improvement thresholds for outcomes and complications of image-guided thermal ablation for the treatment of early stage non-small cell lung cancer, recurrent lung cancer, and metastatic disease.

MATERIALS AND METHODS

A multidisciplinary writing group conducted a comprehensive literature search to identify studies on the topic of interest. Data were extracted from relevant studies and thresholds were derived from a calculation of 2 standard deviations from the weighted mean of each outcome. A modified Delphi technique was used to achieve consensus agreement on the thresholds.

RESULTS

Data from 29 studies, including systematic reviews and meta-analyses, retrospective cohort studies, and single-arm trials were extracted for calculation of the thresholds. The expert writing group agreed on thresholds for local control, overall survival and adverse events associated with image-guided thermal ablation.

CONCLUSION

SIR recommends utilizing the indicator thresholds to review and assess the efficacy of ongoing quality improvement programs. When performance falls above or below specific thresholds, consideration of a review of policies and procedures to assess for potential causes, and to implement changes in practices, may be warranted.

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.

Effectiveness of Thermal Ablation and Stereotactic Radiotherapy Based on Stage I Lung Cancer Histology

PURPOSE

To assess whether the effectiveness of thermal ablation (TA) and stereotactic body radiotherapy (SBRT) as initial treatments for stage I lung cancer varies depending on the histological subtype.

MATERIALS AND METHODS

The 2004-2016 National Cancer Database was queried for patients with American Joint Committee on Cancer stage I lung cancer treated with TA or SBRT. Patients <18 years, those treated with surgery or chemotherapy, or those with unknown survival and follow-up were excluded. TA and SBRT patients were 1:5 propensity score matched separately for each histological subtype to adjust for confounders. Overall survival (OS) was assessed using Cox models.

RESULTS

A total of 28,425 patients were included (SBRT, n = 27,478; TA, n = 947). TA was more likely to be used in Caucasian patients, those with more comorbidities and smaller neuroendocrine tumors (NETs) of the lower lobe, and those whose treatment had taken place in the northeastern United States. After propensity score matching, a cohort with 4,085 SBRT and 817 TA patients with balanced confounders was obtained. In this cohort, OS for TA and SBRT was comparable (hazard ratio = 1.07; 95% confidence interval,0.98-1.18; P = .13), although it varied by histological subtypes: higher OS for TA was observed in patients with non-small cell NETs (vs SBRT hazard ratio = 0.48; 95% confidence interval, 0.24-0.95; P = .04). No significant OS differences between TA and SBRT were noted for adenocarcinomas, squamous cell carcinomas, small cell carcinomas, and non-neuroendocrine large cell carcinomas (each, P > .1).

CONCLUSIONS

OS following TA and SBRT for stage I lung cancer is comparable for most histological subtypes, except that OS is longer after TA in non-small cell NETs.

Survival outcomes for surgical resection versus CT-guided percutaneous ablation for stage I non-small cell lung cancer (NSCLC): a systematic review and meta-analysis

OBJECTIVE

Multiple cohort studies have compared surgical resection with CT-guided percutaneous ablation for patients with stage 1 non-small cell lung cancer (NSCLC); however, the results have been heterogeneous. This systematic review and meta-analysis aims to compare surgery with ablation for stage 1 NSCLC.

METHOD

A search of five databases was performed from inception to 5 July 2020. Studies were included if overall survival (OS), cancer-specific survival (CSS), and/or disease-free survival (DFS) were compared between patients treated with surgical resection versus ablation (radiofrequency ablation (RFA) or microwave ablation (MWA)) for stage 1 NSCLC. Pooled odds ratios (OR) were calculated.

RESULTS

A total of eight studies were included (total 792 patients: 460 resection and 332 ablation). There were no significant differences in 1- to 5-year OS or CSS between surgery versus ablation. There were significantly better 1- and 2-year DFS for surgery over ablation (OR 2.22, 95% CI 1.14-4.34; OR 2.60, 95% CI 1.21-5.57 respectively), but not 3- to 5-year DFS. Subgroup analysis demonstrated no significant OS difference between lobectomy and MWA, but there were significantly better 1- and 2-year OS with sublobar resection (wedge resection or segmentectomy) versus RFA (OR 2.85, 95% CI 1.33-6.10; OR 4.54, 95% CI 2.51-8.21, respectively). In the two studies which only included patients with stage 1A NSCLC, pooled outcomes demonstrated no significant differences in 1- to 3-year OS or DFS between surgery versus ablation.

CONCLUSION

Surgical resection of stage 1 NSCLC remains the optimal choice. However, for non-surgical patients with stage 1A, ablation offers promising DFS, CSS, and OS. Future prospective randomized controlled trials are warranted.

KEY POINTS

• Surgical resection of stage 1 NSCLC remains the optimal choice. • In patients with stage 1A NSCLC who are not surgical candidates, CT-guided microwave or radiofrequency ablation may be an alternative which offers promising disease-free survival and overall survival.

Alternatives to Surgery for Early-Stage Non-Small Cell Lung Cancer: Thermal Ablation

Thermal ablation involves the application of heat or cold energy to the lung under image guidance to eradicate tumors. It is indicated for treatment of early-stage non-small cell lung cancer in nonsurgical patients. Ablation technologies have advanced, such that nearly all small tumors can now be treated safely and effectively. Ablation does not cause a lasting decline in pulmonary function tests and may therefore be used to treat multiple synchronous and metachronous lung tumors, a chief advantage over other treatments. Large series with intermediate- and long-term data have been reported showing favorable overall survival, similar to radiation therapy.

Subsolid pulmonary nodules: Controversy and perspective

Ground glass and part-solid nodules, collectively referred to as subsolid nodules, present a challenge in management, with a high risk of malignancy but, when malignant, demonstrating indolent behavior. Emerging data suggest longer follow-up intervals and shorter duration of follow-up is likely appropriate in these nodules. Additionally, definitive therapy is shifting to less aggressive approaches such as sub-lobar resection. Patients may benefit from individualized approaches, incorporating both patient and imaging features to determine whether treatment is necessary.

Sublobar resection compared with stereotactic body radiation therapy and ablation for early stage non-small cell lung cancer: A National Cancer Database study

OBJECTIVES

To compare the overall survival (OS) outcomes of sublobar resection (SLR) with stereotactic body radiation therapy (SBRT) or ablation for patients with early stage non-small cell lung cancer (NSCLC).

METHODS

Patients with clinical stage I (T1-T2aN0M0) NSCLC from 2004 to 2014 who were treated with SLR, SBRT, or ablation as the sole treatment were identified from the National Cancer Database. OS was estimated using the Kaplan-Meier method and evaluated by log-rank test, univariate and multivariate Cox proportional hazard regression, and propensity score-matched analysis. Relative survival analyses compared with age- and sex-matched US population were performed.

RESULTS

A total of 53,973 patients were identified. The 1-, 2-, 3-, and 5-year relative survival rates were 96%, 90%, 84%, and 71% for SLR (n = 30,451); 93%, 78%, 65%, and 46% for SBRT (n = 22,134); and 90%, 73%, 58%, and 37% for ablation (n = 1388). Propensity score matching resulted in 9967 patients in the SBRT group versus 9967 in the SLR group and 1062 patients in the ablation group versus 1984 in the SLR group. After matching, both SBRT (hazard ratio, 1.559; 95% confidence interval, 1.497-1.623; P < .001) and ablation (hazard ratio, 1.906; 95% confidence interval, 1.730-2.101; P < .001) were associated with shorter OS when compared with SLR. These results persisted in patients with tumor size ≤2 cm.

CONCLUSIONS

Preliminary results suggest SLR may be associated with longer OS in patients with early-stage NSCLC compared with SBRT or ablation. Future prospective, randomized, controlled clinical trials comparing these treatments are needed to confirm these results.

Radiofrequency ablation of stage IA non-small cell lung cancer in patients ineligible for surgery: results of a prospective multicenter phase II trial

Background

A prospective multicenter phase II trial to evaluate the survival outcomes of percutaneous radiofrequency ablation (RFA) for patients with stage IA non-small cell lung cancer (NSCLC), ineligible for surgery.

Methods

Patients with a biopsy-proven stage IA NSCLC, staging established by a positron emission tomography-computed tomography (PET-CT), were eligible. The primary objective was to evaluate the local control of RFA at 1-year. Secondary objectives were 1- and 3-year overall survival (OS), 3-year local control, lung function (prior to and 3 months after RFA) and quality of life (prior to and 1 month after RFA).

Results

Of the 42 patients (mean age 71.7 y) that were enrolled at six French cancer centers, 32 were eligible and assessable. Twenty-seven patients did not recur at 1 year corresponding to a local control rate of 84.38% (95% CI, [67.21–95.72]). The local control rate at 3 years was 81.25% (95% CI, [54.35–95.95]). The OS rate was 91.67% (95% CI, [77.53–98.25]) at 1 year and 58.33% (95% CI, [40.76–74.49]) at 3 years. The forced expiratory volume was stable in most patients apart from two, in whom we observed a 10% decrease. There was no significant change in the global health status or in the quality of life following RFA.

Conclusion

RFA is an efficient treatment for medically inoperable stage IA NSCLC patients. RFA is well tolerated, does not adversely affect pulmonary function and the 3-year OS rate is comparable to that of stereotactic body radiotherapy, in similar patients.

Trial registration

ClinicalTrials.gov Identifier NCT01841060 registered in November 2008.

Comparison study of computed tomography-guided radiofrequency and microwave ablation for pulmonary tumors: A retrospective, case-controlled observational study

BACKGROUND

The aim of this study was to compare the safety, efficacy, and prognostic value of radiofrequency ablation (RFA) and microwave ablation (MWA) for lung tumors.

METHODS

Between March 2012 and January 2018, 238 patients with lung cancer were treated with MWA (139, 58.4%) or RFA (99, 41.6%) in our center. Patient and tumor characteristics, complications, complete ablation (CA) rate, and prognosis were compared between the groups. Meta-analysis was used to systematically compare the outcomes of RFA and MWA for the treatment of lung tumors.

RESULTS

Ablation was successfully completed in all patients and no procedure-related death occurred. The total complication rates in the RFA and MWA groups were 24.2% (24/99) and 16.5% (23/139), respectively, and there was no statistically significant difference (P = 0.142). The initial and total CA rates were similar at P > 0.05 (RFA vs. MWA: initial CA, 97.0% vs. 96.4%; total CA, 99.0% vs. 98.6%, respectively). During follow-up, there was no significant difference in median progression-free (RFA vs. MWA: 12.5 months, 95% confidence interval [CI] 5.002-19.998 vs. 9.5 months, 95% CI 6.623-12.377; P = 0.673) or overall survival (RFA vs. MWA: 33 months, 95% CI 27.070-38.930 vs. 30 months, 95% CI, 18.482-41.518; P = 0.410) between the groups. Combined with the results of published comparison studies, meta-analysis further confirmed that the outcomes of these two treatments were similar.

CONCLUSION

Both RFA and MWA are safe and effective treatments with a survival benefit for selected patients with primary and metastatic lung tumors.

A National Cancer Database Analysis of Radiofrequency Ablation versus Stereotactic Body Radiotherapy in Early-Stage Non-Small Cell Lung Cancer

PURPOSE

To compare overall survival (OS) after radiofrequency (RF) ablation and stereotactic body radiotherapy (SBRT) at high-volume centers in patients with early-stage non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Cases in the National Cancer Database of stage 1a and 1b NSCLC treated with primary RF ablation or SBRT from 2004 to 2014 were included. Patients treated at low-volume centers, defined as facilities below the 95th percentile in volume of cases performed, were excluded. Outcomes measured include OS and rate of 30-day readmission. The Kaplan-Meier method was used to estimate OS. The log-rank test was used to compare survival curves. Propensity score matched cohort analysis was performed. P < .05 was considered statistically significant.

RESULTS

The final cohort comprised 4,454 cases of SBRT and 335 cases of RF ablation. Estimated median survival and follow-up were 38.8 months and 42.0 months, respectively. Patients treated with RF ablation had significantly more comorbidities (P < .001) and higher risk for an unplanned readmission within 30 days (hazard ratio = 11.536; P < .001). No difference in OS for the unmatched groups was found on multivariate Cox regression analysis (P = .285). No difference was found in the matched groups with 1-, 3-, and 5-year OS of 85.5%, 54.3%, and 31.9% in the SBRT group vs 89.3%, 52.7%, and 27.1% in the RF ablation group (P = .835).

CONCLUSIONS

No significant difference in OS was seen between patients with early-stage NSCLC treated with RF ablation and SBRT.

Repeated percutaneous microwave ablation for local recurrence of inoperable Stage I nonsmall cell lung cancer

BACKGROUND

The safety and effectiveness of repeated computed tomography-guided percutaneous microwave ablation (MWA) in the management of local recurrence (LR) in patients with medically inoperable Stage I nonsmall cell lung cancer (NSCLC) were retrospectively evaluated.

MATERIALS AND METHODS

From February 2008 to August 2014, 104 patients with medically inoperable Stage I NSCLC received MWA. Patients with LR were given repeat MWA. The clinical outcomes and complications of repeat MWA for LR were evaluated.

RESULTS

At a median follow-up of 47 months, LR occurred in 24/104 (23.1%) patients within 12 ± 8 months after MWA. LR rates were higher in tumors> 3.5 cm than that of tumors ≤3.5 cm (35.7% vs. 18.4%). Local control of the repeat MWA was achieved in 21 of 24 (87.5%) patients. Overall survival (OS) and progress-free survival (PFS) for patients without LR were similar to that of with LR and receiving repeat MWA (OS: 48 m vs. 41.5 m; PFS: 42 m vs. 32 m). The OS rates were 100%, 74.6%, 60.6%, and 27% for patients without LR at 1, 2, 3, and 5 years, and they were 96.4%, 69.5%, 60.6%, and 26.1% for patients with repeat MWA for LR. Repeat MWA for LR was not associated with more significant complications.

CONCLUSION

The LR was higher in tumors> 3.5 cm than that of in tumors ≤3.5 cm. For patients with LR, it was feasible and effective to use MWA repeatedly to achieve the similar OS and PFS as patients without LR. No additional complications were reported in the repeat MWA compared to the original MWA.

Micropapillary and/or Solid Histologic Subtype Based on Pre-Treatment Biopsy Predicts Local Recurrence After Thermal Ablation of Lung Adenocarcinoma

BACKGROUND

To investigate whether histologic subtyping from biopsies can predict local recurrence after thermal ablation for lung adenocarcinoma.

METHODS

Patients treated with CT-guided thermal ablation for lung adenocarcinoma that had pre-ablation needle biopsy with analysis of histologic components were identified. Age, gender, smoking status, treatment indication (primary stage 1 tumor versus salvage), histologic subtype, ground-glass radiographic appearance, tumor size, ablation modality, and ablation margin were evaluated in relation to time to local recurrence (TTLR). Cumulative incidence of recurrence (CIR) was calculated using competing risks analysis and compared across groups using Fine and Grey method with clustering. Multivariate analysis was conducted with stepwise regression.

RESULTS

There were 53 patients with 57 tumors diagnosed as adenocarcinoma on pre-ablation biopsy and with histologic subtype analysis. Of these, 19% (11) had micropapillary components, 14% (8) had solid components, and 26% (15) had micropapillary and/or solid components. In the univariate analysis, solid (subdistribution hazard ratio [SHR] = 4.04, p = 0.0051, 95% confidence interval [CI] = 1.52-10.7), micropapillary (SHR = 3.36, p = 0.01, CI = 1.33-8.47), and micropapillary and/or solid components (SHR = 5.85, p = 0.00038, CI = 2.21-15.5) were significantly correlated with shorter TTLR. On multivariate analysis, the presence of micropapillary and/or solid component (SHR = 11.4, p = 0.00021, CI: 3.14-41.3) was the only independent predictor of TTLR. The 1-, 2-, and 3-year CIR in patients with micropapillary and/or solid components was 33, 49, and 66% compared to 5, 14, and 18% in patients with no micropapillary or solid components on biopsy specimens.

CONCLUSION

Micropapillary and/or solid histologic components identified in pre-ablation biopsy are associated with shorter TTLR after thermal ablation of lung adenocarcinoma.

Decision Making in Interventional Oncology: Ablative Options in the Lung

Image-guided ablation is safe and effective for the treatment of both primary and metastatic tumors in the lung. This article reviews the three most commonly used ablative options: radiofrequency ablation, microwave ablation, and cryoablation. We describe the advantages of each ablation modality in the lung and how to choose the most appropriate ablation device based on patient and tumor characteristics. The optimal technique for lung ablation is discussed and technical tips for improving clinical outcome are described.

Lung Ablation: Whats New?

Lung cancer had an estimated incidence of 221,200 in 2015, making up 13% of all cancer diagnoses. Tumor ablation is an important treatment option for nonsurgical lung cancer and pulmonary metastatic patients. Radiofrequency ablation has been used for over a decade with newer modalities, microwave ablation, cryoablation, and irreversible electroporation presenting as additional and possibly improved treatment options for patients. This minimally invasive therapy is best for small primary lesions or favorably located metastatic tumors. These technologies can offer palliation and sometimes cure of thoracic malignancies. This article discusses the current available technologies and techniques available for tumor ablation.

Clinical experiences with microwave thermal ablation of lung malignancies

Approximately 30% of early stage lung cancer patients are not surgical candidates due to medical co-morbidities, poor cardiopulmonary function and advanced age. These patients are traditionally offered chemotherapy and radiation, which have shown relatively modest improvements in mortality. For over a decade, percutaneous image-guided ablation has emerged as a safe, cost-effective, minimally invasive treatment alternative for patients who would otherwise not qualify for surgery. Although radiofrequency ablation (RFA) is currently the most extensively studied and widely utilised technique in the treatment of lung malignancies, there is a growing body of evidence that microwave ablation (MWA) has several unique benefits over RFA and cryoablation in the lung. This article reviews our institution's clinical experiences in the treatment of lung malignancies with MWA including patient selection, procedural technique, imaging follow-up, treatment outcomes and comparison of ablation techniques.

The Top Three Health Care Developments Impacting the Practice of Interventional Radiology in the Next Decade

OBJECTIVE

We discuss three health care trends that will have a profound impact on interventional radiology (IR) in the next decade.

CONCLUSION

Precision medicine, representing the next frontier of medicine, will bring opportunities and challenges to the field. Significant changes in payment models may prove beneficial to the subspecialty if proactive steps are taken by its members. Finally, shifts in population demographics are predicted to increase demand for services while intensifying the need to cultivate a complementary workforce.

Radiofrequency ablation in primary non-small cell lung cancer: What a radiologist needs to know

Lung cancer continues to be one of the leading causes of death worldwide. In advanced cases of lung cancer, a multimodality approach is often applied, however with poor local control rates. In early non-small cell lung cancer (NSCLC), surgery is the standard of care. Only 15-30% of patients are eligible for surgical resection. Improvements in imaging and treatment delivery systems have provided new tools to better target these tumors. Stereotactic body radiation therapy (SBRT) has evolved as the next best option. The role of radiofrequency ablation (RFA) is also growing. Currently, it is a third-line option in stage 1 NSCLC, when SBRT cannot be performed. More recent studies have demonstrated usefulness in recurrent tumors and some authors have also suggested combination of RFA with other modalities in larger tumors. Following the National Lung Screening Trial (NLST), screening by low-dose computed tomography (CT) has demonstrated high rates of early-stage lung cancer detection in high-risk populations. Hence, even considering the current role of RFA as a third-line option, in view of increasing numbers of occurrences detected, the number of potential RFA candidates may see a steep uptrend. In view of all this, it is imperative that interventional radiologists be familiar with the techniques of lung ablation. The aim of this article is to discuss the procedural technique of RFA in the lung and review the current evidence regarding RFA for NSCLC.

Percutaneous CT-guided microwave ablation as maintenance after first-line treatment for patients with advanced NSCLC

BACKGROUND

Systemic therapy is recommended for advanced non-small-cell lung cancer (NSCLC). However, conventional first-line treatment has generated a plateau in response rate of 25% to 35%. Few studies have shown patients benefit from microwave ablation (MWA) in combination with radiotherapy and chemotherapy. This study aims to evaluate safety and efficacy of percutaneous computed tomography-guided MWA as maintenance after first-line treatment for patients with advanced NSCLC.

METHODS

Patients with histologically verified NSCLC stage IIIB or IV between January 2010 and March 2014 were involved. After completion of first-line treatment with partial response or stable disease, 35 patients with 39 tumors underwent 39 MWA procedures. Complications, progression-free survival (PFS), overall survival (OS), and correlated predictors were analyzed.

RESULTS

During a median follow-up of 17.7 months and 10.8 months after initial MWA, local efficacy was 87.2%, median MWA-related local control time was 10.6 months, and tumor size was the only predictor (P=0.002). Median MWA-related PFS, MWA-related OS, PFS, and OS were 5.4, 10.6, 11.8 and 17.7 months, respectively. Local efficacy was significantly correlated with MWA-related PFS (P=0.003), MWA-related OS (P=0.000), and OS (P=0.001). There were no procedure-specific deaths. Total incidence of major complications was 12.8%, including pneumothorax resolved by closed pleural drainage and pneumonia controlled by antibiotics in a short time.

CONCLUSION

This study concluded two points, including: 1) patients benefited from MWA as maintenance both in local control and survival; 2) as maintenance MWA was superior to conventional maintenance therapy with improved survival and well-tolerated complications. Therefore, MWA was a safe and effective maintenance after first-line treatment in patients with advanced NSCLC.

Triaging early-stage lung cancer patients into non-surgical pathways: who, when, and what?

More lung cancer patients are being diagnosed at an earlier stage due to improved diagnostic imaging techniques, a trend that is expected to accelerate with the dissemination of lung cancer screening. Surgical resection has always been considered the standard treatment for patients with early-stage non-small cell lung cancer (NSCLC). However, non-surgical treatment options for patients with early-stage NSCLC have evolved significantly over the past decade with many new and exciting alternative treatments now available. These alternative treatments include radiofrequency ablation (RFA), microwave ablation (MWA), percutaneous cryoablation therapy (PCT), photodynamic therapy (PDT) and external beam radiation therapy (EBRT), including stereotactic body radiation therapy (SBRT) and accelerated hypofractionated radiation therapy. We describe the established alternatives to surgical resection, their advantages and disadvantages, potential complications and efficacy. We then describe the optimal treatment approach for patients with early-stage NSCLC based on tumor operability, size and location. Finally, we discuss future directions and whether any alternative therapies will challenge surgical resection as the treatment of choice for patients with operable early-stage lung cancer.

Radiofrequency ablation of stage IA non-small cell lung cancer in medically inoperable patients: Results from the American College of Surgeons Oncology Group Z4033 (Alliance) trial

BACKGROUND

This study evaluated the 2-year overall survival rate, adverse event rate, local control rate, and impact on pulmonary function tests for medically inoperable patients with stage IA non-small cell lung cancer (NSCLC) undergoing computed tomography (CT)-guided radiofrequency ablation (RFA) in a prospective, multicenter trial.

METHODS

Fifty-four patients (25 men and 29 women) with a median age of 76 years (range, 60-89 years) were enrolled from 16 US centers; 51 patients were eligible for evaluation (they had biopsy-proven stage IA NSCLC and were deemed medically inoperable by a board-certified thoracic surgeon). Pulmonary function tests were performed within the 60 days before RFA and 3 and 24 months after RFA. Adverse events were recorded and categorized. Patients were followed with CT and fludeoxyglucose positron emission tomography. Local control rate and recurrence patterns were analyzed.

RESULTS

The overall survival rate was 86.3% at 1 year and 69.8% at 2 years. The local tumor recurrence-free rate was 68.9% at 1 year and 59.8% at 2 years and was worse for tumors > 2 cm. In the 19 patients with local recurrence, 11 were re-treated with RFA, 9 underwent radiation, and 3 underwent chemotherapy. There were 21 grade 3 adverse events, 2 grade 4 adverse events, and 1 grade 5 adverse event in 12 patients within the first 90 days after RFA. None of the grade 4 or 5 adverse events were attributable to RFA. There was no significant change in the forced expiratory volume in the first second of expiration or the diffusing capacity of lung for carbon monoxide after RFA. A tumor size less than 2.0 cm and a performance status of 0 or 1 were associated with statistically significant improved survival of 83% and 78%, respectively, at 2 years.

CONCLUSIONS

RFA is a single, minimally invasive procedure that is well tolerated in medically inoperable patients, does not adversely affect pulmonary function tests, and provides a 2-year overall survival rate that is comparable to the rate reported after stereotactic body radiotherapy in similar patients.

An economic analysis of sublobar resection versus thermal ablation for early-stage non-small-cell lung cancer

PURPOSE

To compare medical costs for a matched-pair cohort of Medicare patients with early-stage non-small-cell lung cancer (NSCLC) who underwent treatment with sublobar resection or thermal ablation.

MATERIALS AND METHODS

Patients at least 65 years of age with stage IA/IB NSCLC treated with sublobar resection or thermal ablation from 2007 to 2009 were identified from Surveillance, Epidemiology, and End Results/Medicare-linked data and matched by propensity scores. The primary outcome of interest, cost from the payer's perspective, was derived from Medicare claims data. A partitioned inverse probability-weighted estimator was used to calculate mean and median treatment-related costs and costs at 1, 3, 12, 18, and 24 months after treatment. Baseline characteristics, Kaplan-Meier survival curves, and calculated cost variables were compared between the two groups.

RESULTS

The final matched cohort of 128 patients had similar baseline characteristics and overall survival (P = .52). Patients who underwent ablation had significantly lower treatment-related costs than those who underwent sublobar resection (P < .001). The difference in median treatment-related cost was $16,105. At 1 month, 3 months, and 12 months after treatment, cumulative costs remained significantly different (P ≤ .011). Lower cost associated with ablations performed in the outpatient setting was a major contributor to the differences between the two treatment modalities, although inpatient ablations maintained a small cost advantage over sublobar resections.

CONCLUSIONS

Among matched Medicare patients with stage I NSCLC, thermal ablation resulted in significantly lower treatment-related costs and cumulative medical costs 1 month, 3 months, and 12 months after treatment compared with sublobar resection.

Radiofrequency ablation for early-stage nonsmall cell lung cancer

This review examines studies of radiofrequency ablation (RFA) of nonsmall cell lung cancer (NSCLC) and discusses the role of RFA in treatment of early-stage NSCLC. RFA is usually performed under local anesthesia with computed tomography guidance. RFA-associated mortality, while being rare, can result from pulmonary events. RFA causes pneumothorax in up to 63% of cases, although pneumothorax requiring chest drainage occurs in less than 15% of procedures. Other severe complications are rare. After RFA of stage I NSCLC, 31–42% of patients show local progression. The 1-, 2-, 3-, and 5-year overall survival rates after RFA of stage I NSCLC were 78% to 100%, 53% to 86%, 36% to 88%, and 25% to 61%, respectively. The median survival time ranged from 29 to 67 months. The 1-, 2-, and 3-year cancer-specific survival rates after RFA of stage I NSCLC were 89% to 100%, 92% to 93%, and 59% to 88%, respectively. RFA has a higher local failure rate than sublobar resection and stereotactic body radiation therapy (SBRT). Therefore, RFA may currently be reserved for early-stage NSCLC patients who are unfit for sublobar resection or SBRT. Various technologies are being developed to improve clinical outcomes of RFA for early-stage NSCLC.