Comparison of therapeutic results from radiofrequency ablation and stereotactic body radiotherapy in solitary lung tumors measuring 5 cm or smaller

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.

Comparison of clinical outcomes between cone beam CT-guided thermal ablation and helical tomotherapy in pulmonary metastases from hepatocellular carcinoma

Objective

This retrospective study compares the clinical results of cone beam CT (CBCT)-guided thermal ablation with those of helical tomotherapy in hepatocellular carcinoma (HCC) patients with pulmonary metastases.

Methods

A total of 110 patients undergoing thermal ablation or helical tomotherapy for pulmonary metastases from April 2014 to December 2020 were included in the study. The endpoints were local tumor progression-free survival (LTPFS), overall survival (OS), and complications. Univariate and multivariate analyses using the Cox proportional hazard model were conducted to identify independent factors (univariate: P < 0.1; multivariate: P < 0.05). The Kaplan–Meier method was used to calculate the LTPFS and OS rates.

Results

The results of 106 patients were taken into the final analysis. The 1- and 3-year LTPFS rates were 50 and 19% for the thermal ablation group and 65 and 25% for the helical tomotherapy group. The median LTPFS in the thermal ablation group was 12.1 months, while it was 18.8 months in the helical tomotherapy group (P = 0.25). The 1- and 3-year OS rates were 75 and 26% for the thermal ablation group and 77 and 37% for the helical tomotherapy group. The median OS was 18.0 months in the thermal ablation group and 23.4 months in the helical tomotherapy group (P = 0.38). The multivariate analyses found that α-fetoprotein (AFP) at <400 ng/ml (P = 0.003) was significantly associated with better LTPFS. Tumor number <3 and AFP <400 ng/ml were favorable prognostic factors for OS. There were no grades 3–5 adverse events in both groups. Grade 2 was recorded in three patients (4.8%) in the thermal ablation group and two patients (4.7%) in the helical tomotherapy group.

Conclusions

For pulmonary metastases from HCC, CBCT-guided thermal ablation and helical tomotherapy provided comparable clinical effects and safety.

Percutaneous local tumor ablation vs. stereotactic body radiotherapy for early-stage non-small cell lung cancer: a systematic review and meta-analysis

BACKGROUND

Percutaneous local tumor ablation (LTA) and stereotactic body radiotherapy (SBRT) have been regarded as viable treatments for early-stage lung cancer patients. The purpose of this study was to compare the efficacy and safety of LTA with SBRT for early-stage non-small cell lung cancer (NSCLC).

METHODS

PubMed, Embase, Cochrane library, Ovid, Google scholar, CNKI, and CBMdisc were searched to identify potential eligible studies comparing the efficacy and safety of LTA with SBRT for early-stage NSCLC published between January 1, 1991, and May 31, 2021. Hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were applied to estimate the effect size for overall survival (OS), progression-free survival (PFS), locoregional progression (LP), and adverse events.

RESULTS

Five studies with 22,231 patients were enrolled, including 1443 patients in the LTA group and 20,788 patients in the SBRT group. The results showed that SBRT was not superior to LTA for OS (HR = 1.03, 95% CI: 0.87-1.22, P = 0.71). Similar results were observed for PFS (HR = 1.09, 95% CI: 0.71-1.67, P = 0.71) and LP (HR = 0.66, 95% CI: 0.25-1.77, P = 0.70). Subgroup analysis showed that the pooled HR for OS favored SBRT in patients with tumors sized >2 cm (HR = 1.32, 95% CI: 1.14-1.53, P = 0.0003), whereas there was no significant difference in patients with tumors sized ≤2 cm (HR = 0.93, 95% CI: 0.64-1.35, P = 0.70). Moreover, no significant differences were observed for the incidence of severe adverse events (≥grade 3) (OR = 1.95, 95% CI: 0.63-6.07, P = 0.25) between the LTA group and SBRT group.

CONCLUSIONS

Compared with SBRT, LTA appears to have similar OS, PFS, and LP. However, for tumors >2 cm, SBRT is superior to LTA in OS. Prospective randomized controlled trials are required to determine such findings.

INPLASY REGISTRATION NUMBER

INPLASY202160099.

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.

Percutaneous Image-Guided Ablation of Lung Tumors

Tumors of the lung, including primary cancer and metastases, are notoriously common and difficult to treat. Although surgical resection of lung lesions is often indicated, many conditions disqualify patients from being surgical candidates. Percutaneous image-guided lung ablation is a relatively new set of techniques that offers a promising treatment option for a variety of lung tumors. Although there have been no clinical trials to definitively compare its efficacy to those of traditional treatments, lung ablation is widely practiced and generally accepted to be safe and effective. Especially encouraging results have recently emerged for cryoablation, one of the newer ablative techniques. This article reviews the indications, techniques, contraindications, and complications of percutaneous image-guided ablation of lung tumors with special attention to cryoablation and its recent developments in protocol optimization.

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.

Chest wall toxicity after stereotactic radiation in early lung cancer: a systematic review

Background

Radiation-induced chest wall pain (cwp) and rib fracture (rf) are late adverse effects after stereotactic body radiation therapy (sbrt) for stage i non-small-cell lung cancer (nsclc); however, the literature about their incidence and risk factors shows variability. We performed a systematic review to determine the pooled incidence of cwp and rf in the relevant population.

Methods

A literature search using the prisma (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines considered English publications in medline and embase from January 1996 to August 2017. Abstracts were screened, followed by full-text review and data extraction.

Results

The database searches identified 547 records. Twenty-eight publications comprising 3892 patients met the inclusion criteria. Median reported ages and follow-up durations fell into the ranges 67-82 years and 12-84 months. Prescriptions fell into the range of 40-70 Gy in 3-10 fractions. Despite study heterogeneity, the pooled incidences of cwp and rf were estimated to be 8.94% and 5.27% respectively. Nineteen studies reported cwp grade: 58 of 308 patients (18.8%) experienced grades 3-4 cwp (no grade 5 events reported). Thirteen studies reported rf grade: grades 3-4 rf were observed in 9 of 113 patients (7.96%). A high chest wall V30 was an important predictor of cwp and rf.

Conclusions

In patients with stage i nsclc, rates of cwp and rf after sbrt are low; however, tumour location, accurate toxicity reporting, and dose-fractionation schemes might alter those rates. Prospective correlation with dosimetry and quality of life assessment will further improve the understanding of cwp and rf after sbrt.

Survival Outcomes of Treatment with Radiofrequency Ablation, Stereotactic Body Radiotherapy, or Sublobar Resection for Patients with Clinical Stage I Non-Small-Cell Lung Cancer: A Single-Center Evaluation

PURPOSE

To retrospectively compare the outcomes of radiofrequency (RF) ablation, stereotactic body radiotherapy (SBRT), and sublobar resection (SLR) in patients with stage I non-small-cell lung cancer (NSCLC) at a single center.

MATERIALS AND METHODS

Overall, 289 patients (38 RF ablation, 58 SBRT, and 193 SLR) were included. Kaplan-Meier curves were generated, multiple propensity score was estimated using a multinomial logistic regression model, and relationships between treatments and outcomes were assessed using a Cox proportional hazard model. Hazard ratios (HRs) for death from any cause and disease progression or death from any cause were examined by a crude model, an inverse probability of treatment weighting (IPTW) model, and an IPTW model adjusted for missing variables.

RESULTS

The 5-year overall and progression-free survival rates were 58.9% and 39.9%, respectively, for RF ablation; 42.0% and 34.9%, respectively, for SBRT; and 85.5% and 75.9%, respectively, for SLR. Significantly longer survival time and lower HR were observed for SLR than other treatments. However, after statistical adjustment, these relationships were not significant except for reduced HR of disease progression or death from any cause of SLR compared to RF ablation in the IPTW model. The median hospital stays for RF ablation, SBRT, and SLR were 6.5, 6, and 16 days, respectively. Adverse events of grade 3 or higher occurred only in 11 SLR cases.

CONCLUSIONS

SLR achieved the longest survival. However, after statistical adjustment, there were no significant outcome differences among RF ablation, SBRT, and SLR, except for 1 model. RF ablation or SBRT may be alternative treatments for selected patients with early-stage NSCLC.

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.

Stereotactic Body Radiation Therapy Versus Nonradiotherapeutic Ablative Procedures (Laser/Cryoablation and Electrocautery) for Early-Stage Non-Small Cell Lung Cancer

BACKGROUND

Despite the fact that stereotactic body radiation therapy (SBRT) is the only recommended first-line therapy for inoperable early-stage non-small cell lung cancer (NSCLC), several thermal ablative procedures (TAPs; defined herein as laser/cryoablation and electrocautery) are available. Studies showing outcomes of these procedures and how they compare with SBRT are scarce. We sought to evaluate the comparative efficacy of SBRT versus TAPs using the National Cancer Database (NCDB).

METHODS

The NCDB was queried for patients with early-stage NSCLC who did not undergo surgical resection. Treatment-specific inclusion criteria were applied to select for patients receiving either TAPs or SBRT. Univariate logistic regression and Cox proportional hazards modeling were performed, and Kaplan-Meier curves were generated. Serial propensity matches were performed using a modified greedy 8→n matching 1:1 algorithm.

RESULTS

A total of 27,734 patients were analyzed; 26,725 underwent SBRT and 1,009 underwent TAPs. Patients who received SBRT were older and more likely to have clinical stage IB (vs IA) disease. Despite this, SBRT was associated with longer median overall survival (mOS; 37.7 vs 33.5 months; P=.001) and 1-, 2-, and 5-year OS rates compared with the TAPs cohort (86.7% vs 83.1%, 67.5% vs 62.7%, and 30.6% vs 26.9%, respectively; P=.001). Upon propensity matching, improved OS with SBRT remained, with a mOS of 40.4 versus 33.4 months and 1-, 2-, and 5-year OS rates of 89.0% versus 82.9%, 69.7% versus 62.7%, and 34.4% versus 26.4%, respectively (P=.003).

CONCLUSIONS

Despite being associated with more higher-risk factors, SBRT was associated with higher OS compared with TAPs for treatment of nonoperative patients diagnosed with early-stage NSCLC. However, causation cannot be implied owing to the inherent limitations of large heterogeneous datasets such as the NCDB.

Expert consensus on image-guided radiofrequency ablation of pulmonary tumors: 2018 edition

Lung cancer ranks first in incidence and mortality in China. Surgery is the primary method to cure cancer, but only 20-30% of patients are eligible for curative resection. In recent years, in addition to surgery, other local therapies have been developed for patients with numerous localized primary and metastatic pulmonary tumors, including stereotactic body radiation therapy and thermal ablative therapies through percutaneously inserted applicators. Percutaneous thermal ablation of pulmonary tumors is minimally invasive, conformal, repeatable, feasible, cheap, has a shorter recovery time, and offers reduced morbidity and mortality. Radiofrequency ablation (RFA), the most commonly used thermal ablation technique, has a reported 80-90% rate of complete ablation, with the best results obtained in tumors < 3 cm in diameter. Because the clinical efficacy of RFA of pulmonary tumors has not yet been determined, this clinical guideline describes the techniques used in the treatment of localized primary and metastatic pulmonary tumors in nonsurgical candidates, including mechanism of action, devices, indications, techniques, potential complications, clinical outcomes, post-ablation surveillance, and use in combination with other therapies. In the future, the role of RFA in the treatment of localized pulmonary tumors should ultimately be determined by evidence from prospective randomized controlled trials comparing sublobar resection or stereotactic body radiation therapy.

Radiofrequency Ablation Effectively Treated Focal Recurrence of Mesothelioma

A 55-year-old man with malignant pleural mesothelioma underwent multimodality treatment comprising induction chemotherapy followed by extrapleural pneumonectomy and radiation therapy. After 2.5 years, focal recurrence occurred, with computed tomography revealing a tumor in the left cardiophrenic angle. Surgery was considered a problem for the patient because of the previous extrapleural pneumonectomy and difficult tumor location. Radiofrequency ablation was therefore performed; the course was uneventful, and there was no recurrence. Radiofrequency ablation should be considered an option to treat recurrence of malignant pleural mesothelioma.

Ablative Approaches for Pulmonary Metastases

Pulmonary metastases are common in patients with cancer for which surgery is considered a standard approach in appropriately selected patients. A number of patients are not candidates for surgery due to a medical comorbidities or the extent of surgery required. For these patients, noninvasive or minimally invasive approaches to ablate pulmonary metastases are potential treatment strategies. This article summarizes the rationale and outcomes for non-surgical treatment approaches, including radiotherapy, radiofrequency and microwave ablation, for pulmonary metastases.

Radiation-induced organizing pneumonia after stereotactic body radiotherapy for lung tumor

The aim of this retrospective study was to investigate characteristics of organizing pneumonia (OP) after stereotactic body radiotherapy (SBRT) for lung tumor. Between September 2010 and June 2014, patients who were diagnosed as Stage I lung cancer and treated with SBRT at our institution were included in this study. A total of 78 patients (47 males with a median age of 80 years) were analyzed. The median follow-up period was 23 months. Five patients (6.4%) developed OP at 6-18 months after SBRT. The cumulative incidence of OP was 4.3% (95% confidence interval [CI], 1.1-11.0) and 8.2% (95% CI, 2.9-17.0) at 1 and 2 years, respectively. Tumor location (superior and middle lobe vs inferior lobe) was shown to be a borderline significant factor for the occurrence of OP ( P: = 0.069). In the subgroup analysis of patients with a radiographic follow-up period at least 6 months, or who died within 6 months after SBRT, 7 of 72 patients (9.7%) developed Grade 2 or 3 radiation pneumonitis (G2/3 RP) at 2-4 months after SBRT. A statistically significant association between G2/3 RP in the subacute phase and OP was shown ( P: = 0.040). In two of the five patients who developed OP, the symptoms and radiographic change were improved rapidly by corticosteroid administration. One patient had relapsed OP after suspending the treatment and re-administration was required. Three patients with minor symptoms were managed without corticosteroid administration and OP resolved without any relapse. The radiation-induced OP should be considered as one of the late lung injuries after SBRT for lung tumors.

A prospective clinical trial of radiofrequency ablation for pulmonary metastases

Pulmonary oligometastases can be treated by local treatment options, such as resection, radiofrequency ablation (RFA), and radiotherapy, in selected patients. In the present study, 67 patients with 115 pulmonary metastases were treated, and all the lesions were treated by RFA and followed with a computed tomography scan. The local control, overall survival (OS), progression-free survival (PFS) and treatment-related toxicity were observed. Median follow-up duration after the initial RFA was 24 months (range, 3-39 months). The median PFS from RFA was 14 months [95% confidence interval (CI), 11.6-16.4]. The 6-, 12- and 18-month PFS rates were 82.1, 55.7 and 27.5%, respectively. The median OS rate from RFA was 24 months (95% CI, 18.2-29.8). The 1-, 2- and 3-year OS rates were 83.6, 46.3 and 14.3%, respectively. Primary tumor was significantly correlated to PFS and OS on multivariate analysis, and other variates showed no significance. Therefore, RFA is safe for patient treatment and can be considered as a promising treatment option for patients with pulmonary metastases.