Percutaneous microwave ablation for early-stage non-small cell lung cancer (NSCLC) in the elderly: A promising outlook

Potential of Thermal Ablation Combined with Immunotherapy in Peripheral Lung Tumors: A Review and Prospect

BACKGROUND

Lung tumors are prevalent malignancies associated with a high mortality rate, imposing significant medical and societal burdens. Although immunotherapy shows promise in improving survival, response rates are relatively modest. Thermal ablation can not only eliminate tumor cells directly but also enhance antitumor immunity response, thus manifesting a remarkable propensity to synergize with immunotherapy.

SUMMARY

In this review, we provided a brief overview of the application of thermal ablation in peripheral lung tumors. We summarized the patient selection of thermal ablation. We highlighted the potential of thermal ablation to augment the antitumor immune response, offering a promising avenue for combined therapies. We summarized studies assessing the synergistic effects of thermal ablation and immunotherapy in preclinical and clinical settings. Lastly, we underscored the urgent issues that warrant in-depth exploration when applying thermal ablation and immunotherapy to lung tumor patients.

KEY MESSAGES

This review emphasized the prospects of using thermal ablation combined with immunotherapy in patients with peripheral lung tumors. However, further research is needed to enhance and optimize this treatment strategy.

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.

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.

Microwave ablation combined with anti-PD-1/CTLA-4 therapy induces an antitumor immune response to renal cell carcinoma in a murine model

The study was designed to evaluate the efficiency of microwave ablation (MWA) in combination with anti-programmed death receptor 1 (anti-PD-1)/cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) in renal cell carcinoma (RCC) treatment. After tumors were established on C57/BL6 mice, MWA treatment and/or immune checkpoint inhibitor (ICI) treatment to the mice were performed. Tumor volume was recorded every 7 days. A rechallenge test was conducted on mice with tumors in the left kidney to explore the systemic establishment of antitumor immunity on day 7. In this study, during the 21-day observation period, tumors were continued to grow in all groups. However, compared with the tumor growth rate in MWA or control group, the rate in the ICI or MWA+ICI groups was decreased. Moreover, the population of CD8+T-cells was increased only in the MWA+ICI group, while that of regulatory T cells was decreased in the MWA, ICI, and MWA+ICI groups. Additionally, the MWA+ICI group had the highest interferon-γ level among all groups. Furthermore, histopathological examination revealed that CTLA-4 expression in distant tumors was reduced in the ICI and MWA + ICI groups. MWA treatment increased PD-L1/PD-1 expression; however, after the combination treatment with ICI, PD-L1/PD-1 expression was decreased. According to the rechallenge test, mice (16.7%) in the MWA group, ICI group (50%), and MWA+ICI group (66.7%) exhibited successful tumor rejection, whereas no mice in the control group exhibited the capability of tumor rejection. Overall, the systemic antitumor immunity induced by MWA was boosted when combined with anti-PD-1/CTLA-4 treatment in an RCC murine model.

Current trends in image-guided chest interventions

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

Role of Fluorodeoxyglucose-PET in Interventional Radiology

Fluorodeoxyglucose (FDG)-PET has expanding applications in the field of interventional radiology. FDG-PET provides both qualitative and quantitative assessments of malignancy, infection, and inflammation. These assessments can assist interventional radiologists in selecting the most appropriate treatment options for their oncology patients. FDG-PET is also useful for evaluating the response to interventional treatments and in predicting the prognosis of oncology patients. Finally, FDG-PET can assist the interventional radiologist in diagnosing and monitoring response to treatment of infection and inflammation. Nevertheless, there is a need for additional prospective studies to further establish the role of FDG-PET in these applications.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Microwave ablation treatment for medically inoperable stage I non-small cell lung cancers: long-term results

OBJECTIVES

In the present study, we aim to show the results of microwave ablation (MWA) for medically inoperable stage I non-small cell lung cancers (NSCLCs) with long-term follow-up.

METHODS

From Feb 2011 to Mar 2016, patients with histologically proven clinical stage I NSCLC were treated with CT-guided MWA and retrospectively analyzed. The primary end point was overall survival (OS). Secondary end points included disease-free survival (DFS), cancer-specific survival (CSS), and complications.

RESULTS

A total of 105 patients with 105 lesions underwent MWA. The mean age was 70.7 years (range: 40-86 years), and the mean diameter of all lesions was 2.40 cm (range: 0.9-4.0 cm). Adenocarcinoma was the most common histological type (77, 73.3%), followed by squamous cell carcinomas (21, 20%) and undefined NSCLC (7, 6.7%). With a median follow-up of 54.8 months, the median DFS was 36.0 months, and 1-, 3-, and 5-year DFS rates were 89.5%, 49.4%, and 42.7%, respectively. The median CSS and OS were 89.8 and 64.2 months, respectively. The OS rate was 99% at 1 year, 75.6% at 3 years, and 54.1% at 5 years, while the CSS rates were 99%, 78.9%, and 60.9%, respectively. Patients with stage IB lesions had significant shorter DFS (22.3 months vs. undefined, HR: 11.5, 95%CI: 5.85-22.40) and OS (37.3 vs. 89.8 months, HR: 8.64, 95% CI: 4.49-16.60) than IA disease.

CONCLUSION

MWA is a safe, effective, and potentially curative therapy for medically inoperable stage I NSCLC patients.

KEY POINTS

• In this multicenter retrospective study which included 105 patients, we found the median overall survival (OS) was 64.2 months. The OS rate was 99% at 1 year, 75.6% at 3 years, and 54.1% at 5 years. • Procedures were technically successful and well tolerated in all patients. Most MWA complications were mild or moderate.

Safety and utility of performing CT-guided biopsies of pulmonary lesions that arise after radiotherapy

This study aimed to evaluate the feasibility, safety and usefulness of performing computed tomography (CT)-guided biopsies of pulmonary lesions that arise after radiotherapy. Seventeen patients (14 males and 3 females; median age: 69 years, range: 48-84 years) underwent CT-guided biopsies of pulmonary lesions that occurred in lung regions that had previously been treated with radiotherapy. Three patients underwent CT-guided biopsies twice, and thus, the total number of procedures was 20. We reviewed the subjects' medical records and images, and evaluated the rate for obtaining pathological diagnosis with the biopsy sample, subsequent clinical course, and complications associated with the procedure. In 19 of 20 procedures (95%), the CT-guided biopsy resulted in a pathological diagnosis being obtained. In 14 procedures, the pathological results were consistent with the patients' clinical courses. In the remaining 5 procedures, the lesions were pathologically diagnosed as benign, but they increased in size thereafter; so the lesions were considered to be clinically malignant. The results were considered to represent sampling errors. There were 3 minor complications (slight pneumothorax which did not require drainage) (3/20, 15%), and there were no major complications. In conclusion, performing CT-guided biopsies of pulmonary lesions that arise after radiotherapy appears to be feasible, safe and useful.

Image-guided percutaneous microwave ablation of early-stage non-small cell lung cancer

Although surgical lobectomy with systematic mediastinal lymph node evaluation is considered as the "gold standard" for management of early stage non-small cell lung cancer (NSCLC), image-guided percutaneous thermal ablation has been increasingly used for medically inoperable patients. Radiofrequency ablation (RFA) is a research-based technique that has the most studies for medically inoperable early-stage NSCLC. Other thermal ablation techniques used to treat pulmonary tumors include microwave ablation (MWA), cryoablation and laser ablation. MWA has several advantages over RFA including reduced procedural time, reduced heat-sink effect, large ablation zones, decreased susceptibility to tissue impedance, and simultaneous use of multiple antennae. This review article highlights the most relevant updates of MWA for the treatment of early-stage NSCLC, including mechanism of action, clinical outcomes, potential complications, the existing technique problems and future directions.

Comparative clinical study on microwave ablation combined with gemcitabine and cisplatin or combined with pemetrexed and cisplatin in treatment of advanced NSCLC

OBJECTIVE

Solving the limitations of single chemotherapy in the treatment of non-small cell lung cancer (NSCLC).

METHODS

About 100 patients with NSCLC treated in First Hospital of Jiaxing, Zhejiang from June 2016 to June 2018 were selected and randomly divided into MPC group and MGC group, with 50 cases in each group. The patients in MPC group were treated with microwave ablation (MWA) combined with PC while patients in MGC group were given MWA combined with gemcitabine plus cisplatin (GC). The therapeutic effects of the two groups as well as the complications and adverse reactions (ADRs) were observed and recorded.

RESULTS

There was no significant difference in disease response rate (MPC group 33.3% vs MGC group 32.0%), disease control rate (MPC group 86.4% vs MGC group 78.0%) and overall survival (1-, 2- and 3-year survival, MPC group 65%, 59%, 32.7% vs MGC group 58%, 46%, 30%) between the two groups. In addition, the ADR myelosuppression was slighter in MPC group. There were 12 cases (23%) developed myelosuppression in the MPC group and 20 cases (42%) in MGC group, with a significant difference between the two groups (P < 0.05). The treatment was interrupted for 0 case (0%) in MPC group because of myelosuppression while 4 cases (8.3%) in MGC group.

CONCLUSION

The two therapeutic regimens have similar efficacy in treatment of advanced NSCLC, but MPC causes slighter myelosuppression and can be the first-line therapy for advanced NSCLC.

Flexible bronchoscopy-guided microwave ablation in peripheral porcine lung: a new minimally-invasive ablation

Background

Transbronchial lung biopsy is an important approach to diagnose peripheral lung cancer, but bronchoscopy based treatment options are limited and poorly studied. A flexible bronchoscopy-guided water-cooled microwave ablation (MWA) catheter was developed to evaluate the feasibility and safety both in ex vivo and in vivo porcine models.

Methods

Using direct penetration of the catheter through the surface of ex vivo porcine lung, ablations (n=9) were performed at 70, 80, 90 W for 10 minutes. Temperatures of the catheter and 10, 15, 20 mm away from the tip were measured. Under bronchoscopy conditions in porcine lung, ablations (n=18, 6 in ex vivo and 12 in vivo) were performed at 80 W for 5 minutes. Computed tomography (CT) was acquired perioperative, 24 hours, 2 weeks, and 4 weeks post ablation. Ablation zones were excised at 24 hours and 4 weeks respectively. Long-axis diameter (Dl) and short-axis diameter (Ds) were measured and tissues were sectioned for pathological examination.

Results

In-ex vivo lung, the temperature at 20 mm removed was over 60 °C at 80 W for 288±26 seconds. The ablations under bronchoscopic conditions were successful in-ex vivo and in vivo lung. No complications occurred during the procedures. Coagulation necrosis was visible at 24 hours, and repaired fibrous tissue was seen at 4 weeks.

Conclusions

The flexible bronchoscopy-guided water-cooled MWA is feasible and safe. This early animal data holds promise of MWA becoming a potential therapeutic tool for Peripheral Lung Cancers.

Safety and clinical outcomes of computed tomography-guided percutaneous microwave ablation in patients aged 80 years and older with early-stage non-small cell lung cancer: A multicenter retrospective study

Background

Previous studies have documented the therapeutic value of computed tomography (CT)‐guided percutaneous microwave ablation (MWA) for early‐stage non‐small cell lung cancer (NSCLC). However, few studies have focused on patients aged 80 years and older. This retrospective study aimed to evaluate the safety and clinical outcomes of CT‐guided percutaneous MWA in patients aged 80 years and older with early‐stage peripheral NSCLC.

Methods

A retrospective analysis of 63 patients aged 80 years and older with cT1a‐2bN0M0 peripheral NSCLC who underwent CT‐guided percutaneous MWA was performed between January 2008 and January 2018 at 11 hospitals in Shandong Province, China.

Results

The median follow‐up time was 21.0 months. The overall median survival time was 50 months. The cancer‐specific median survival time was not reached in five years. The one‐, two‐, three‐, four‐, and five‐year overall survival rates were 97.1%, 92.6%, 63.4%, 54.4%, and 32.6%, respectively. The one‐, two‐, and three‐year cancer‐specific survival (CSS) rates were 97.9%, 97.9%, and 69.4%, respectively. The four‐ and five‐year CSS rates were not achieved. A total of 14 patients (22.2%) had local progression. The one‐, two‐, three‐, four‐, and five‐year local control rates were 88.8%, 78.8%, 70.3%, 63.9%, and 63.9%, respectively. The mortality rate was 0% within 30 days after the procedure. Major complications included pneumothorax requiring drainage (21.1%), pulmonary infection (4.2%), and pleural effusions requiring drainage (2.8%).

Conclusions

CT‐guided percutaneous MWA is a safe and effective modality for treating patients aged 80 years and older with early‐stage peripheral NSCLC.

A Case Analysis on CT Guided Percutaneous Lung Puncture Biopsy of Lymphocyte Mesenchymal Pneumonia

OBJECTIVE

To explore the application and diagnostic value of high-resolution CT in the process of lymphocytic interstitial pneumonia clinical diagnosis, and analyze one case of CT-guided percutaneous lung biopsy lymphocytic interstitial pneumonia.

METHODS

The medical record of a patient with lymphocyte interstitial pneumonia (LIP) who came to the clinic on 2014-04-22 were analyzed and summarized retrospectively.

RESULTS

The patient was a 55 years old female farmer. The CT-guided percutaneous lung biopsy was performed at her first visit; on 2014-07-09, the patient returned to our outpatient clinic with the main complaint of "1 week of coughing and blood in sputum and phlegm". Pathology consultation report from the PLA General Hospital on 2014-07-29 showed: (right lower lung) pneumonic pseudo-tumor; Zhejiang First Hospital's pathology consultation report on 2014-08-11 showed: lymphocyte interstitial pneumonia.

CONCLUSION

The diagnosis of lymphocyte interstitial pneumonia (LIP) with high-resolution CT may be used to increase its clinical diagnosis rate, reduce misdiagnosis and improve early detection.

Invasive pulmonary aspergillosis secondary to microwave ablation: a multicenter retrospective study

PURPOSE

Invasive pulmonary aspergillosis (IPA) is a life-threatening complication of microwave ablation (MWA) during the treatment of primary or metastatic lung tumors. The purpose of this study was to investigate the clinical, radiological and demographic characteristics and treatment responses of patients with IPA after MWA.

MATERIALS AND METHODS

From January 2011 to January 2016, all patients who were treated by MWA of their lung tumors from six health institutions were enrolled in this study. Patients with IPA secondary to MWA were identified and retrospectively evaluated for predisposing factors, clinical treatment, and outcome.

RESULTS

The incidence of IPA secondary to lung MWA was 1.44% (23/1596). Of the 23 patients who developed IPA, six died as a consequence, resulting in a high mortality rate of 26.1%. Using computed tomography (CT), pulmonary cavitation was the most common finding and occurred in 87.0% (20/23) of the patients. Sudden massive hemoptysis was responsible for one-third of the deaths (2/6). Most patients (22/23) received voriconazole as an initial treatment, and six patients with huge cavities underwent intracavitary lavage. Finally, 17 patients (73.9%) achieved treatment success.

CONCLUSIONS

Lung MWA may be an additional host risk factor for IPA, particularly in elderly patients with underlying diseases and in patients who have recently undergone chemotherapy. Early and accurate diagnosis of IPA after MWA is critical for patient prognosis. Voriconazole should be given as the first-line treatment as early as possible. Bronchial artery embolization or intracavitary lavage may be required in some patients.

Catheter-based alternative treatment for early-stage lung cancer with a high-risk for morbidity

The mainstream treatment modality for early stage non-small cell lung cancer (NSCLC) is surgery; however, many patients are deemed inoperable and warrant alternative therapeutic options. Several minimally invasive catheter-based therapies are emerging as viable alternatives. In this review, we evaluate the outcomes from radiofrequency ablation (RFA), microwave ablation (MWA), cryoablation (CRA) and photodynamic therapy (PDT) for early-stage lung cancer. Novel technical developments have allowed for endobronchial thermal ablation to be conducted in a hybrid theatre setting, which may optimize treatment outcomes and minimise treatment-related complications.

CT-guided percutaneous laser ablation of metastatic lung cancer: three cases report and literature review

Objective

To report the efficacy and safety of CT-guided percutaneous laser ablation (PLA) for metastatic lung tumors.

Methods

Three cases of metastatic lung cancer underwent CT-guided PLA, and we searched for previously published articles on the minimally invasive CT-guided RFA or MWA for lung tumors in recent five years.

Results

With the guidance of CT, all lesions had good prognosis under laser ablation. Case 1 suffering from severe pulmonary dysfunction and diffuse pulmonary bullae, had small pneumothorax. CT scan obtained four months following the ablation showed two lesions had complete responses and one partial response. Case 2 had successful complete response with absent lung mass, and also had a good postoperative condition without any discomfort in the two-month follow-up. Case 3 showed partial response and improved greatly after five months. 962 cases (mean age of 45.7 years, 62.2% male) of 1297 lung tumors with detailed information were identified from 27 articles. Of these cases, the minority manifested complications such as pneumothorax, hemoptysis, hemothorax, pneumonia, pain and fever.

Conclusions

Percutaneous CT-guided PLA could be a safe and promising minimally invasive treatment for patients with primary lung cancer or unresectable pulmonary metastases, especially multineedle PLA in large tumors, which still needs more large-scale prospective studies to convince this method in the future.

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

OBJECTIVE:

The objective of this study was to compare the efficacy and safety of radiofrequency ablation (RFA), cryoablation, and microwave ablation (MWA) for patients with lung malignancies.

METHODS:

We performed a network meta-analysis to identify both direct and indirect evidence from relevant trials by searching PubMed, Embase, and the Cochrane Library to December 31, 2017, for the treatment of malignant lung tumors with the use of RFA, MWA, or cryoablation. We extracted the relevant information from the published studies with a predefined data sheet and assessed the risk of bias with the Cochrane risk of bias tool. The primary outcomes were efficacy (local progression rate and overall survival rate) and safety (major complications rate). We did a random-effects network meta-analysis within a Bayesian framework as well as assessed the quality of evidence contributing to each network estimate using GRADE framework.

RESULTS:

We collected 34 studies eligible which included 1840 participants and 2520 lung malignancies (1318 primary lung cancer and 1202 pulmonary metastatic tumors). The quality of evidence was rated as very low in most comparisons. From the point of local progression rate, RFA and MWA were significantly more effective than cryoablation with odds ratio (OR) of 0.04 (95% confidence interval [CI]: 0.004, 0.38; P = 0.005) and 0.02 (95% CI: 0.002, 0.24; P = 0.001), respectively. No significant difference was found between MWA and RFA with an OR of 0.63 (95% CI: 0.04, 10.39; P = 0.745). Regarding the major complications, RFA, MWA, and cryoablation showed the comparable safety (P > 0.05).

CONCLUSION:

RFA and MWA offer an advantage over cryoablation for patients with malignant lung tumors.

Percutaneous thermal ablation for stage IA non-small cell lung cancer: long-term follow-up

Background

Surgical resection is the most effective curative therapy for non-small cell lung cancer (NSCLC). However, many patients are unable to tolerate resection secondary to poor reserve or comorbid disease. Radiofrequency ablation (RFA) and microwave ablation (MWA) are methods of percutaneous thermal ablation that can be used to treat medically inoperable patients with NSCLC. We present long-term outcomes following thermal ablation of stage IA NSCLC from a single center.

Methods

Patients with stage IA NSCLC and factors precluding resection who underwent RFA or MWA from July 2005 to September 2009 were studied. CT and PET-CT scans were performed at 3 and 6 month intervals, respectively, for first 24 months of follow-up. Factors associated with local progression (LP) and overall survival (OS) were analyzed.

Results

Twenty-one patients underwent 21 RFA and 4 MWA for a total of 25 ablations. Fifteen patients had T1a and six patients had T1b tumors. Mean follow-up was 42 months, median survival was 39 months, and OS at three years was 52%. There was no significant difference in median survival between T1a nodules and T1b nodules (36 vs. 39 months, P=0.29) or for RFA and MWA (36 vs. 50 months, P=0.80). Ten patients had LP (47.6%), at a median time of 35 months. There was no significant difference in LP between T1a and T1b tumors (22 vs. 35 months, P=0.94) or RFA and MWA (35 vs. 17 months, P=0.18). Median OS with LP was 32 months compared to 39 months without LP (P=0.68). Three patients underwent repeat ablations. Mean time to LP following repeat ablation was 14.75 months. One patient had two repeat ablations and was disease free at 40-month follow-up.

Conclusions

Thermal ablation effectively treated or controlled stage IA NSCLC in medically inoperable patients. Three-year OS exceeded 50%, and LP did not affect OS. Therefore, thermal ablation is a viable option for medically inoperable patients with early stage NSCLC.

DDMC-p53 gene therapy with or without cisplatin and microwave ablation

Lung cancer remains the leading cause of death in cancer patients. Severe treatment side effects and late stage of disease at diagnosis continue to be an issue. We investigated whether local treatment using 2-diethylaminoethyl-dextran methyl methacrylate copolymer with p53 (DDMC-p53) with or without cisplatin and/or microwave ablation enhances disease control in BALBC mice. We used a Lewis lung carcinoma cell line to inoculate 140 BALBC mice, which were divided into the following seven groups; control, cisplatin, microwave ablation, DDMC-p53, DDMC-p53 plus cisplatin, DDMC-p53 plus microwave, and DDMC-p53 plus cisplatin plus microwave. Microwave ablation energy was administered at 20 W for 10 minutes. Cisplatin was administered as 1 mL/mg and the DDMC-p53 complex delivered was 0.5 mL. Increased toxicity was observed in the group receiving DDMC-p53 plus cisplatin plus microwave followed by the group receiving DDMC-p53 plus cisplatin. Infection after repeated treatment administration was a major issue. We conclude that a combination of gene therapy using DDMC-p53 with or without cisplatin and microwave is an alternative method for local disease control. However, more experiments are required in a larger model to identify the appropriate dosage profile.

Enhancement of Intratumoral Chemotherapy with Cisplatin with or without Microwave Ablation and Lipiodol. Future Concept for Local Treatment in Lung Cancer

Novel therapies for lung cancer are being explored nowadays with local therapies being the tip of the arrow. Intratumoral chemotherapy administration and local microwave ablation have been investigated in several studies. It has been previously proposed that lipiodol has the ability to modify the microenvironment matrix. In our current study we investigated this theory in BALBC mice. In total 160 BALBC mice were divided in eight groups: a) control, b) cisplatin, c) microwave, d) microwave and lipiodol, e) cisplatin and lipiodol, f) microwave and cisplatin, g) lipiodol and h) lipiodol, cisplatin and microwave. Lewis lung carcinoma cell lines (10⁶) were injected into the right back leg of each mouse. After the 8th day, when the tumor volume was about 100mm³ the therapy application was initiated, once per week for four weeks. Magnetic resonance imaging was performed for each tumor when a mouse died or when sacrificed if they were still alive by the end of the experiment (8-Canal multifunctional spool; NORAS MRI products, Gmbh, Germany). Imaging and survival revealed efficient tumor apoptosis for the groups b,c,d,e and f. However; severe toxicity was observed in group h and no follow up was available for this group after the second week of therapy administration. Lipiodol in its current form does assist in a more efficient way the distribution of cisplatin, as the microwave apoptotic effect. Future modification of lipiodol might provide a more efficient method of therapy enhancement. Combination of drug and microwave ablation is possible and has an efficient apoptotic effect.