Lung ablation: Best practice/results/response assessment/role alongside other ablative therapies

Stereotactic ablative brachytherapy versus percutaneous microwave ablation for early-stage non-small cell lung cancer: a multicenter retrospective study

BACKGROUND

To analyze the efficacy of stereotactic ablative brachytherapy (SABT) and percutaneous microwave ablation (MWA) for the treatment of early-stage non-small cell lung cancer (NSCLC).

METHODS

Patients with early-stage (T1-T2aN0M0) NSCLC who underwent CT-guided SABT or MWA between October 2014 and March 2017 at four medical centers were retrospectively analyzed. Survival, treatment response, and procedure-related complications were assessed.

RESULTS

A total of 83 patients were included in this study. The median follow-up time was 55.2 months (range 7.2-76.8 months). The 1-, 3-, and 5-year overall survival (OS) rates were 96.4%, 82.3%, and 68.4% for the SABT group (n = 28), and 96.4%, 79.7%, and 63.2% for MWA group (n = 55), respectively. The 1-, 3-, and 5-year disease-free survival (DFS) rates were 92.9%, 74.6%, and 54.1% for SABT, and 92.7%, 70.5%, and 50.5% for MWA, respectively. There were no significant differences between SABT and MWA in terms of OS (p = 0.631) or DFS (p = 0.836). The recurrence rate was also similar between the two groups (p = 0.809). No procedure-related deaths occurred. Pneumothorax was the most common adverse event in the two groups, with no significant difference. No radiation pneumonia was found in the SABT group.

CONCLUSIONS

SABT provided similar efficacy to MWA for the treatment of stage I NSCLC. SABT may be a treatment option for unresectable early-stage NSCLC. However, future prospective randomized studies are required to verify these results.

Combination of Local Ablative Techniques with Radiotherapy for Primary and Recurrent Lung Cancer: A Systematic Review

In patients with early-stage or recurrent NSCLC who are unable to tolerate surgery, a benefit could derive only from a systemic therapy or another few forms of local therapy. A systematic review was performed to evaluate the feasibility and the effectiveness of radiotherapy combined with local ablative therapies in the treatment of primary and recurrent lung cancer in terms of toxicity profile and local control rate. Six studies featuring a total of 115 patients who met eligibility criteria and 119 lesions were included. Three studies evaluated lung cancer patients with a medically inoperable condition treated with image-guided local ablative therapies followed by radiotherapy: their local control rate (LC) ranged from 75% to 91.7% with only 15 patients (19.4%) reporting local recurrence after combined modality treatment. The other three studies provided a salvage option for patients with locally recurrent NSCLC after RT: the median follow-up period varied from 8.3 to 69.3 months with an LC rate ranging from 50% to 100%. The most common complications were radiation pneumonitis (9.5%) and pneumothorax (29.8%). The proposed intervention appears to be promising in terms of toxicity profile and local control rate. Further prospective studies are need to better delineate combining LTA-RT treatment benefits in this setting.

The safety and response of CT guided percutaneous cryoablation for lung nodules by 17-gauge needles

BACKGROUND

The safety and efficacy of 17-gauge needles used in CT-guided percutaneous cryoablation for lung nodules were explored in this study. The purpose of the study was to compare the findings with earlier research and multi-center clinical trials that used various needle sizes.

METHODS

Between 2016 and 2020, a retrospective study was conducted with approval from the institutional review board. A total of 41 patients were enrolled, and 71 lung nodules were treated in 63 cryoablation procedures using local anesthesia. Complication rates were recorded, and overall survival rates as well as tumor progression-free rates were calculated using the Kaplan-Meier method.

RESULTS

Self-limited hemoptysis was caused by 12.9% of the procedures, and drainage was required for pneumothoraces resulting from 11.3% of them. The overall survival rates at one, two, three, and four years were 97%, 94%, 82%, and 67%, respectively. The tumor progression-free rates at one, two, three, and four years were 86.2%, 77%, 74%, and 65%, respectively.

CONCLUSION

Cryoablation for lung nodules using 17-Gauge needles can achieve similar rates of survival and tumor control rates, similar or even lower complication rates as compared with other studies and multi-center trials using mixed sized needles.

Temperature Dependence of Thermal Properties of Ex Vivo Porcine Heart and Lung in Hyperthermia and Ablative Temperature Ranges

This work proposes the characterization of the temperature dependence of the thermal properties of heart and lung tissues from room temperature up to > 90 °C. The thermal diffusivity (α), thermal conductivity (k), and volumetric heat capacity (C_v) of ex vivo porcine hearts and deflated lungs were measured with a dual-needle sensor technique. α and k associated with heart tissue remained almost constant until ~ 70 and ~ 80 °C, accordingly. Above ~ 80 °C, a more substantial variation in these thermal properties was registered: at 94 °C, α and k respectively experienced a 2.3- and 1.5- fold increase compared to their nominal values, showing average values of 0.346 mm²/s and 0.828 W/(m·K), accordingly. Conversely, C_v was almost constant until 55 °C and decreased afterward (e.g., C_v = 2.42 MJ/(m³·K) at 94 °C). Concerning the lung tissue, both its α and k were characterized by an exponential increase with temperature, showing a marked increment at supraphysiological and ablative temperatures (at 91 °C, α and k were equal to 2.120 mm²/s and 2.721 W/(m·K), respectively, i.e., 13.7- and 13.1-fold higher compared to their baseline values). Regression analysis was performed to attain the best-fit curves interpolating the measured data, thus providing models of the temperature dependence of the investigated properties. These models can be useful for increasing the accuracy of simulation-based preplanning frameworks of interventional thermal procedures, and the realization of tissue-mimicking materials.

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

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

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.

Lung Ablation with Irreversible Electroporation Promotes Immune Cell Infiltration by Sparing Extracellular Matrix Proteins and Vasculature: Implications for Immunotherapy

Background: This study investigated the sparing of the extracellular matrix (ECM) and blood vessels at the site of lung irreversible electroporation (IRE), and its impact on postablation T cell and macrophage populations. Materials and Methods: Normal swine (n = 8) lung was treated with either IRE or microwave ablation (MWA), followed by sacrifice at 2 and 28 days (four animals/timepoint) after treatment. En bloc samples of ablated lung were stained for blood vessels (CD31), ECM proteins (Collagen, Heparan sulfate, and Decorin), T cells (CD3), and macrophages (Iba1). Stained slides were analyzed with an image processing software (ImageJ) to count the number of positive staining cells or the percentage area of tissue staining for ECM markers, and the statistical difference was evaluated with Student's t-test. Results: Approximately 50% of the blood vessels and collagen typically seen in healthy lung were evident in IRE treated samples at Day 2, with complete destruction within MWA treated lung. These levels increased threefold by Day 28, indicative of post-IRE tissue remodeling and regeneration. Decorin and Heparan sulfate levels were reduced, and it remained so through the duration of observation. Concurrently, numbers of CD3⁺ T cells and macrophages were not different from healthy lung at Day 2 after IRE, subsequently increasing by 2.5 and 1.5-fold by Day 28. Similar findings were restricted to the peripheral inflammatory rim of MWA samples, wherein the central necrotic regions remained acellular through Day 28. Conclusion: Acute preservation of blood vessels and major ECM components was observed in IRE treated lung at acute time points, and it was associated with the increased infiltration and presence of T cells and macrophages, features that were spatially restricted in MWA treated lung.

Feasibility and Safety of Radiofrequency Ablation Guided by Bronchoscopic Transparenchymal Nodule Access in Canines

BACKGROUND

The treatment of pulmonary malignancies remains a challenge. The efficacy and safety of bronchoscopic radiofrequency ablation (RFA) for the treatment of lung cancer are not well elucidated.

OBJECTIVE

This study aimed to evaluate the feasibility and safety of RFA guided by bronchoscopic transparenchymal nodule access (BTPNA) in vivo.

METHODS

In an attempt to determine the parameters of RFA, we first performed RFA in conjunction with automatic saline microperfusion in the lung in vitro with various ablation energy (10, 15, 20, 25, and 30 W) and ablation times (3, 5, 8, and 10 min). The correlation between ablated area and RFA parameter was recorded and analyzed. Further, we conducted a canine study with RFA by BTPNA in vivo, observing the ablation effect and morphological changes in the lung assessed by chest CT and histopathologic examination at various follow-up time points (1 day, n = 3; 30 days, n = 4; 90 days, n = 4). The related complications were also observed and recorded.

RESULTS

More ablation energy, but not ablation time, induced a greater range of ablation area in the lung. Ablation energy applied with 15 W for 3 min served as the appropriate setting for pulmonary lesions ≤1 cm. RFA guided by BTPNA was performed in 11 canines with 100% success rate. Inflammation, congestion, and coagulation necrosis were observed after ablation, which could be repaired within 7 days; subsequently, granulation and fibrotic scar tissue developed after 30 days. No procedure-related complication occurred during the operation or in the follow-up periods.

CONCLUSION

The novel RFA system and catheter in conjunction with automatic saline microperfusion present a safe and feasible modality in pulmonary parenchyma. RFA guided by BTPNA appears to be well established with an acceptable tolerance; it might further provide therapeutic benefit in pulmonary malignancies.

The ECLIPSE Study: Efficacy of cryoablation on metastatic lung tumors with a 5-year follow-up

INTRODUCTION

The ECLIPSE study aimed to assess the feasibility and efficacy of cryoablation for local tumor control in patients with pulmonary metastatic disease over five years of follow-up.

METHODS

ECLIPSE was a prospective, multicenter, single-arm study which included patients treated with cryoablation if they had 1-5 metastatic lung tumors, each with a diameter of ≤ 3.5 cm. Patients were followed up over the course of five years. The primary endpoint was local tumor control, both per tumor and per patient; secondary endpoints included cancer-specific survival, overall survival (OS), and quality of life. Quality of life was assessed using the Karnofsky Performance Score, the Eastern Cooperative Oncology Group Performance Score, and the Short Form-12 health survey.

RESULTS

The study included 40 patients across 4 sites (3 US and 1 European). A total of 60 metastatic pulmonary tumors were treated with 48 cryoablation procedures. Overall local tumor control rates were 87.9% (29/33) and 79.2% (19/24) per tumor, and 83.3% (20/24) and 75.0% (15/20) per patient, at 3 and 5 years respectively. A total of 5 treated patients demonstrated local progression throughout the duration of the study. Disease specific survival rate was of 74.8% at 3 years and 55.3% at 5 years while overall survival at 3 and 5 years were of 63.2% and 46.7% respectively. Patient quality of life scores did not reach statistical significance.

CONCLUSIONS

Cryoablation is an effective means of long-term local tumor control in patients with metastatic pulmonary tumors.

Efficacy of Tract Embolization After Percutaneous Pulmonary Radiofrequency Ablation

PURPOSE

To evaluate the efficacy of tract embolization technique using gelatin sponge slurry with iodinated contrast medium (GSSI) to reduce the incidence of pneumothorax and chest tube placement after computed tomography-guided lung radiofrequency ablation (RFA).

MATERIALS AND METHODS

In this single-institute retrospective study, we examined all patients with metastatic cancer treated from January 2016 to December 2019 by interventional radiologists with computed tomography-guided lung RFA. Since 2017 in our institution, we have applied a tract embolization technique using GSSI for all RFA. Patients were included into those who underwent lung RFA performed either with GSSI (Group A) or without GSSI (Group B). Univariate and multivariate analyses were performed between the two groups to identify risk factors for pneumothorax and chest tube placement, including patient demographics and lesion characteristics.

RESULTS

This study included 116 patients (54 men, 62 women; mean age, 65 ± 11 years) who underwent RFA. Group A comprised 71 patients and Group B comprised 45 patients. Patients who underwent tract embolization had a significantly lower incidence of pneumothorax (Group A, 34% vs. Group B, 62%; p < 0.001) and chest tube insertion (Group A, 10% vs. Group B, 29%; p < 0.01). No embolic complications occurred. The hospitalization stay was significantly shorter in patients who underwent tract embolization (mean, 1.04 ± 0.2 days; p = 0.02).

CONCLUSION

Tract embolization after percutaneous lung RFA significantly reduced the rate of post-RFA pneumothorax and chest tube placement and was safer than the standard lung RFA technique.

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.

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

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

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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.

Long-Term Outcomes in Percutaneous Radiofrequency Ablation for Histologically Proven Colorectal Lung Metastasis

Introduction

To evaluate the long-term outcome of image-guided radiofrequency ablation (RFA) when treating histologically confirmed colorectal lung metastasis in terms of overall survival (OS), progression-free survival (PFS) and local tumour control (LTC).

Materials and Methods

Retrospective single-centre study. Consecutive RFA treatments of histologically proven lung colorectal metastases between 01/01/2008 and 31/12/14. The primary outcome was patient survival (OS and PFS). Secondary outcomes were local tumour progression (LTP) and complications. Prognostic factors associated with OS/ PFS were determined by univariate and multivariate analyses.

Results

Sixty patients (39 males: 21 females; median age 69 years) and 125 colorectal lung metastases were treated. Eighty percent (n = 48) also underwent lung surgery for lung metastases. Mean metastasis size (cm) was 1.4 ± 0.6 (range 0.3–4.0). Median number of RFA sessions was 1 (1–4). During follow-up (median 45.5 months), 45 patients died (75%). The estimated OS and PFS survival rates at 1, 3, 5, 7, 9 years were 96.7%, 74.7%, 44.1%, 27.5%, 16.3% (median OS, 52 months) and 66.7%, 31.2%, 25.9%, 21.2% and 5.9% (median PFS, 19 months). The LTC rate was 90% with 6 patients developing LTP with 1-, 2-, 3- and 4-year LTP rates of 3.3%, 8.3%, 10.0% and 10.0%. Progression-free interval < 1 year (P = 0.002, HR = 0.375) and total number of pulmonary metastases (≥ 3) treated (P = 0.037, HR = 0.480) were independent negative prognostic factors. Thirty-day mortality rate was 0% with no intra-procedural deaths.

Conclusion

The long-term OS and PFS following RFA for the treatment of histologically confirmed colorectal lung metastases demonstrate comparable oncological durability to surgery.

Electronic supplementary material

The online version of this article (10.1007/s00270-020-02623-1) contains supplementary material, which is available to authorized users.

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.

Endobronchial Ultrasound-Guided Radiofrequency Ablation of Lung Tumors and Mediastinal Lymph Nodes: A Preclinical Study in Animal Lung Tumor and Mediastinal Adenopathy Models

Radiofrequency ablation (RFA) can be a therapeutic option in medically inoperable lung cancer patients. In this study, we evaluated a prototype bipolar RFA device applicator that can be deployed from a standard endobronchial ultrasound (EBUS) bronchoscope to determine feasibility and histopathological analysis in animal models. Rabbit lung cancers were created by transbronchial injection of VX2 rabbit cancer cells. Once the tumors were developed, they were ablated transpleurally, under EBUS guidance using the prototype RFA device. The animals were then sacrificed for specimen resection. Pig inflammatory lung pseudo-tumors and lymphadenopathy were created by transbronchial injection of a talc paste and ablated transbronchially under EBUS guidance. Pigs were evaluated at 5 days, 2 weeks, and 4 weeks following ablation by bronchoscopy and cone beam computed tomography before necropsy. Nicotinamide adenine dinucleotide hydrogen diaphorase staining was employed to measure the ablation area. Twenty-four VX2 rabbit tumors were ablated. The total ablated area ranged from 0.6 to 3.0 cm² (mean: 1.8 cm²), corresponding to a total energy range of 1 to 6 kJ. Six pig lung pseudo-tumors and 5 mediastinal lymph nodes were ablated. Adjacent airway ulceration was observed in 3 ablations of lymph nodes. These airway complications resolved within 4 weeks of RFA without any treatment. There was no hemoptysis, air embolism, respiratory distress, or other serious complication noted. In these 2 animal models, we provide evidence that EBUS-guided bipolar RFA is feasible and histopathology shows that can ablate lung tumors and mediastinal lymph nodes under real-time ultrasound guidance.

Comparing cryoablation and microwave ablation for the treatment of patients with stage IIIB/IV non-small cell lung cancer

The aim of the present study was to compare the safety and efficacy of cryoablation (CA) and microwave ablation (MWA) as treatments for non-small cell lung cancer (NSCLC). Patients with stage IIIB or IV NSCLC treated with CA (n=45) or MWA (n=56) were enrolled in the present study. The primary endpoint was progression-free survival (PFS); the secondary endpoints included overall survival (OS) time and adverse events (AEs). The median PFS times between the two groups were not significantly different (P=0.36): CA, 10 months [95% confidence interval (CI), 7.5-12.4] vs. MWA, 11 months (95% CI, 9.5-12.4). The OS times between the two groups were also not significantly different (P=0.07): CA, 27.5 months (95% CI, 22.8-31.2 months) vs. MWA, 18 months (95% CI, 12.5-23.5). For larger tumors (>3 cm), patients treated with MWA had significantly longer median PFS (P=0.04; MWA, 10.5 months vs. CA, 7.0 months) and OS times (P=0.04; MWA, 24.5 months vs. CA, 14.5 months) compared patients treated with CA. However, for smaller tumors (≤3 cm), median PFS (P=0.79; MWA, 11.0 months vs. CA, 13.0 months) and OS times (P=0.39; MWA, 30.0 months vs. CA, 26.5 months) between the two groups did not differ significantly. The incidence rates of AEs were similar in the two groups (P>0.05). The number of applicators, tumor size and length of the lung traversed by applicators were associated with a higher risk of pneumothorax and intra-pulmonary hemorrhage in the two groups. Treatment with CA resulted in significantly less intraprocedural pain compared with treatment with MWA (P=0.001). Overall, the present study demonstrated that CA and MWA were comparably safe and effective procedures for the treatment of small tumors. However, treatment with MWA was superior compared with CA for the treatment of large tumors.

Imaging of Novel Oncologic Treatments in Lung Cancer Part 2: Local Ablative Therapies

Conventional approaches to the treatment of early-stage lung cancer have focused on the use of surgical methods to remove the tumor. Recent progress in radiation therapy techniques and in the field of interventional oncology has seen the development of several novel ablative therapies that have gained widespread acceptance as alternatives to conventional surgical options in appropriately selected patients. Local control rates with stereotactic body radiation therapy for early-stage lung cancer now approach those of surgical resection, while percutaneous ablation is in widespread use for the treatment of lung cancer and oligometastatic disease for selected other malignancies. Tumors treated with targeted medical and ablative therapies can respond to treatment differently when compared with conventional therapies. For example, after stereotactic body radiation therapy, radiologic patterns of posttreatment change can mimic disease progression, and, following percutaneous ablation, the expected initial increase in the size of a treated lesion limits the utility of conventional size-based response assessment criteria. In addition, numerous treatment-related side effects have been described that are important to recognize, both to ensure appropriate treatment and to avoid misclassification as worsening tumor. Imaging plays a vital role in the assessment of patients receiving targeted ablative therapy, and it is essential that thoracic radiologists become familiar with these findings.

Chronic Obstructive Pulmonary Disease and Lung Cancer: Underlying Pathophysiology and New Therapeutic Modalities

Chronic obstructive pulmonary disease (COPD) and lung cancer are major lung diseases affecting millions worldwide. Both diseases have links to cigarette smoking and exert a considerable societal burden. People suffering from COPD are at higher risk of developing lung cancer than those without, and are more susceptible to poor outcomes after diagnosis and treatment. Lung cancer and COPD are closely associated, possibly sharing common traits such as an underlying genetic predisposition, epithelial and endothelial cell plasticity, dysfunctional inflammatory mechanisms including the deposition of excessive extracellular matrix, angiogenesis, susceptibility to DNA damage and cellular mutagenesis. In fact, COPD could be the driving factor for lung cancer, providing a conducive environment that propagates its evolution. In the early stages of smoking, body defences provide a combative immune/oxidative response and DNA repair mechanisms are likely to subdue these changes to a certain extent; however, in patients with COPD with lung cancer the consequences could be devastating, potentially contributing to slower postoperative recovery after lung resection and increased resistance to radiotherapy and chemotherapy. Vital to the development of new-targeted therapies is an in-depth understanding of various molecular mechanisms that are associated with both pathologies. In this comprehensive review, we provide a detailed overview of possible underlying factors that link COPD and lung cancer, and current therapeutic advances from both human and preclinical animal models that can effectively mitigate this unholy relationship.

Combined microwave ablation and antiangiogenic therapy to increase local efficacy

Purpose: We aim to evaluate the efficacy, safety and survival time of microwave ablation (MWA) with adjuvant antiangiogenic therapy-endostatin in animal models.Material and methods: A total of 40 rabbits successfully implanted with VX2 tumors were randomly assigned to four experimental groups: Group A underwent only microwave ablation of the tumors; Group B received only antiangiogenic drugs endostatin; Group C received endostatin immediately after MWA; Group D followed up without treatment.Results: Two months post-treatment, tumor sizes of Group A and Group C were reduced to 1.936 ± 0.373 cm³ and 1.592 ± 0.382 cm³, respectively. However, tumors grew to 15.091 ± 1.735 cm³ and 47.825 ± 7.664 cm³ in Group B and the control group. Three months post-treatment, tumor sizes in Group A and Group C maintained as 1.395 ± 0.394 cm³ and 1.482 ± 0.305 cm³, significantly smaller than Group B (35.277 ± 6.019 cm³). All animals in the control group died, while four (40%) survived in Group B (Endo Group). The numbers of survivals in Groups A and C were seven (70%) and eight (80%), respectively. The lowest metastasis rate (2/10, 20%) was observed in Group C (combination therapy).Conclusion: The combination of MWA and antiangiogenic therapy triggered a significant reduction in the growth rate and metastases of tumors and may potentially improve survivals.

Comparison of Conventional and Cone-Beam CT for Monitoring and Assessing Pulmonary Microwave Ablation in a Porcine Model

PURPOSE

To compare cone-beam computed tomography (CT) with conventional CT for assessing the growth and postprocedural appearance of pulmonary microwave ablation zones.

MATERIALS AND METHODS

A total of 17 microwave ablations were performed in porcine lung in vivo by applying 65 W for 5 minutes through a single 17-gauge antenna. Either CT (n = 8) or CBCT (n = 9) was used for guidance and ablation zone monitoring at 1-minute intervals. Postprocedural noncontrast images were acquired with both modalities. Three independent readers measured the length, width, cross-sectional area, and circularity of the ablation zones on gross tissue samples and CT and cone-beam CT images. The measurements were compared via linear mixed-effects models for postprocedural appearance and with a polynomial mixed effects model for ablation zone growth curves.

RESULTS

On postprocedural images, the differences between cone-beam CT and CT in mean length (3.84 vs 3.86 cm; Δ = -0.02; P = .70), width (2.61 vs 2.56 cm; Δ = 0.06; P = .46), area (7.84 vs 7.65 cm²; Δ = 0.19; P = .35), and circularity (0.85 vs 0.85; Δ = 0.01; P = .62) were not statistically significant after accounting for intersubject and interrater variability. Also, there was no significant difference between CT and cone-beam CT growth curves of the ablation zones during monitoring in terms of length (p_Int. = 1.00; p_Lin.Slope = 0.52; p_Quad.Slope = 0.69); width (p_Int. = 0.83; p_Lin.Slope = 0.98; p_Quad.Slope = 0.79), area (p_Int. = 0.47; p_Lin.Slope = 0.27; p_Quad.Slope = 0.57), or circularity (p_Int. = 0.54; p_Lin.Slope = 0.74; p_Quad.Slope = 0.80). Both CT and cone-beam CT overestimated gross pathologic observations of ablation length, width, and area (P < .001 for all).

CONCLUSIONS

Cone-beam CT was similar to conventional CT when assessing the growth, final size, and shape of pulmonary microwave ablation zones and may be useful for monitoring and evaluating microwave ablations in the lung.

Percutaneous radiofrequency ablation in the treatment of pulmonary malignancies: efficacy, safety and predictive factors

Purpose

The purpose of this study was to evaluate the efficacy, safety and predictive factors of RFA of primary and secondary lung malignancies.

Patients and Methods

79 patients with 129 primary and secondary lung malignancies were enrolled in a retrospective study. We treated 74 pulmonary metastases of colorectal cancer, 13 malignant melanoma lesions, 13 renal cancer metastases, 5 primary lung malignancies and 24 tumors of other different entities. All patients were considered to be unsuitable candidates for surgery, radiotherapy or chemotherapy. The primary endpoint was local tumor control, secondary endpoints were overall survival, safety and predictive factors, e.g. distance to pleura, vessels and bronchi.

Results

The median tumor size was 1.2 cm (0.5–3.0 cm). After a median follow-up of 14 months (3–81 months), the LTC was 85.3 %. There were 34 lesions (26.4%) with complete remission, 48 (37.2 %) partial remission, 28 (21.7%) stable disease and 19 lesions (14.7%) with progressive disease. We evaluated an OS of 27 months. Pneumothorax in 19 cases (14.7%) and pleural effusion in 2 cases (1.6 %) were the leading complications (CTCAE, 5 grade III adverse events). The only significant influence regarding the outcome after RFA was the initial tumor size (p = 0.01). Distance to vessel, bronchi, and pleura showed no significant effect (p = 0.81; p = 0.82; p = 0.80).

Clinical assessment of computed tomography guided radiofrequency ablation in the treatment of inoperable patients with pulmonary tumors

Background

To enhance our understanding of the feasibility, effectiveness, safety and quality of life (QoL) of radiofrequency ablation (RFA) for inoperable patients with pulmonary tumors.

Methods

The data of 88 patients with pulmonary tumors undergoing RFA were collected. Proof of malignancy was obtained by biopsy in all patients. Diagnoses included non-small cell lung cancer (NSCLC) in 74 patients and pulmonary metastases in 14 patients. Patients underwent computed tomography (CT)-guided RFA according to standard protocol and had a 2-year follow-up. Results assessment included feasibility (correct placement of the ablation probe into all targeted tumors), effectiveness (overall survival rate and local control rate), safety (treatment-related complication and changes in pulmonary function) and QoL.

Results

One hundred and thirty-four RFAs were successfully conducted in 88 patients with 96 nodules. Correct placement of ablation probe into targeted tumors with completion of the planned treatment protocol was feasible in all 88 (100%) patients and no procedure-related deaths occurred. Major complication rate was 4.5% (4/88), which consisted of symptomatic pneumothorax (2/88) and high fever (2/88). No significant worsening of pulmonary function was observed. Tumors shrank obviously at 6 months after RFA with a statistically significance (P<0.001).The overall survival rate in 6 months, 1 year and 2 years were 100%, 95.5% and 70.5%, respectively while the local control rate in 6 months, 1 year and 2 years were 92.1%, 87.5% and 51.1% respectively. There was no significant difference of overall survival rate and local control rate between NSCLC and metastatic carcinoma. No significant worsening of QoL was observed.

Conclusions

CT-guided RFA is a feasible, effective and safe therapy for inoperable patients with pulmonary tumors. However, RFA could not obviously improve the QoL in the patients with pulmonary tumors. More prospective studies comparing RFA with standard non-surgical treatment options were needed.

A review of immune therapy in cancer and a question: can thermal therapy increase tumor response?

Immune therapy is a successful cancer treatment coming into its own. This is because checkpoint molecules, adoptive specific lymphocyte transfer and chimeric antigen T-cell (CAR-T) therapy are able to induce more durable responses in an increasing number of malignancies compared to chemotherapy. In addition, immune therapies are able to treat bulky disease, whereas standard cytotoxic therapies cannot treat large tumour burdens. Checkpoint inhibitor monoclonal antibodies are becoming widely used in the clinic and although more complex, adoptive lymphocyte transfer and CAR-T therapies show promise. We are learning that there are nuances to predicting the successful use of the checkpoint inhibitors as well as to specific-antigen adoptive and CAR-T therapies. We are also newly aware of a here-to-fore unrealised natural force, the status of the microbiome. However, despite better understanding of mechanisms of action of the new immune therapies, the best responses to the new immune therapies remain 20-30%. Likely the best way to improve this somewhat low response rate for patients is to increase the patient's own immune response. Thermal therapy is a way to do this. All forms of thermal therapy, from fever-range systemic thermal therapy, to high-temperature HIFU and even cryotherapy improve the immune response pre-clinically. It is time to test the immune therapies with thermal therapy in vivo to test for optimal timing of the combinations that will best enhance tumour response and then to begin to test the immune therapies with thermal therapy in the clinic as soon as possible.