Microwave ablation plus chemotherapy improved progression-free survival of advanced non-small cell lung cancer compared to chemotherapy alone

A retrospective study comparing the efficacy of microwave ablation and stereotactic body radiotherapy in colorectal cancer lung metastases

The purpose of the present study was to assess and compare the efficacy of microwave ablation (MWA) and stereotactic body radiotherapy (SBRT) in the treatment of lung metastases from patients with colorectal cancer (CRC) and to identify the preferable treatment modality based on patient and tumor characteristics. Records of 118 patients with CRC with a total of 307 lung metastases who underwent SBRT or MWA between January 2015 and December 2022 were retrospectively analyzed, including the essential clinicopathological information on patients (age, sex and underlying diseases), diagnosis and treatment information [primary tumor site, levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9], imaging data [diameter of lung metastasis, location of the metastasis (i.e., whether or not the tumor was adjacent to the vessel or bronchus) and internal features] and follow-up data (postoperative therapy, complications or adverse effects and survival outcomes). For statistical analysis of the local tumor progression (LTP), disease-free survival and overall survival (OS) rates, Cox regression analysis, along with the Kaplan-Meier method adjusted using inverse probability of treatment weighting (IPTW), were performed. The median follow-up duration in the present study was 31.5 months. Multivariable Cox regression analysis revealed that the CEA level, metastasis diameter and internal features were independent predictors of OS. In the IPTW-adjusted analysis, no significant difference in the 1-year OS rate was observed between the SBRT and MWA groups (92.9 vs. 93.9%; P=0.483); however, a notable discrepancy in the treatment modalities was noted, leading to significant differences in the 2- and 3-year OS rates (65.9 vs. 57.6%, P=0.001, and 44.7 vs. 36.4%, P<0.001, respectively). A significant interaction effect for the treatment modality was observed for LTP (P=0.021). In conclusion, the present study revealed that SBRT and MWA have similar therapeutic effects in terms of prolonging the survival of patients with CRC with lung metastases; however, regarding the local control of lung metastases, MWA is associated with a number of significant advantages.

A prognostic model for predicting progression-free survival in patients with advanced non-small cell lung cancer after image-guided microwave ablation plus chemotherapy

OBJECTIVES

This study aimed to build and validate a prediction model that can predict progression-free survival (PFS) in patients with advanced non-small cell lung cancer (NSCLC) after image-guided microwave ablation (MWA) plus chemotherapy.

METHODS

Data from a previous multi-center randomized controlled trial (RCT) was used and assigned to either the training data set or the external validation data set according to the location of the centers. Potential prognostic factors were identified by multivariable analysis in the training data set and used to construct a nomogram. After bootstraps internal and external validation, the predictive performance was evaluated by concordance index (C-index), Brier Score, and calibration curves. Risk group stratification was conducted using the score calculated by the nomogram. Then a simplified scoring system was built to make risk group stratification more convenient.

RESULTS

In total, 148 patients (training data set: n = 112; external validation data set: n = 36) were enrolled for analysis. Six potential predictors were identified and entered into the nomogram, including weight loss, histology, clinical TNM stage, clinical N category, tumor location, and tumor size. The C-indexes were 0.77 (95% CI, 0.65-0.88, internal validation) and 0.64 (95% CI, 0.43-0.85, external validation). The survival curves of different risk groups also displayed significant distinction (p < 0.0001).

CONCLUSIONS

We found weight loss, histology, clinical TNM stage, clinical N category, tumor location, and tumor size were prognostic factors of progression after receiving MWA plus chemotherapy and constructed a prediction model that can predict PFS.

CLINICAL RELEVANCE STATEMENT

The nomogram and scoring system will assist physicians to predict the individualized PFS of their patients and decide whether to perform or terminate MWA and chemotherapy according to the expected benefits.

KEY POINTS

• Build and validate a prognostic model using the data from a previous randomized controlled trial to predict progression-free survival after receiving MWA plus chemotherapy. • Weight loss, histology, clinical TNM stage, clinical N category, tumor location, and tumor size were prognostic factors. • The nomogram and scoring system published by the prediction model can be used to assist physicians to make clinical decisions.

The efficacy and safety of thermal ablation for patients with lung malignancy: a meta-analysis of 12 studies in China

BACKGROUND

Thermal ablation has been increasingly used in the treatment of lung cancer in recent years. This meta-analysis aims to investigate the therapeutic effect and safety of thermal ablation plus chemotherapy as compared with chemotherapy alone in treating patients with lung malignancy in China based on current evidence.

METHODS

Databases including PubMed, Web of Science, Embase and the Cochrane Library were searched for clinical reports. Additional literature search was also performed by searching the reference list of included studies and latest reviews. Raw data including objective response rate, disease control rate, progression-free survival, overall survival and the incidence of major complication were extracted and pooled.

RESULTS

A total of 12 studies in China including 1282 patients with lung malignancy were included in this meta-analysis. The number of studies that reported data of objective response rate, disease control rate, progression-free survival, overall survival and major complication was 8, 7, 7, 6 and 7, respectively. The combination therapy of thermal ablation plus chemotherapy showed a significantly better efficacy in improving objective response rate (odds ratio = 2.73; P < 0.001) and disease control rate (odds ratio = 2.43; P < 0.001) as compared with chemotherapy alone. Thermal ablation was also a significant protective factor for progression-free survival (hazard ratio = 0.43; P < 0.001) and overall survival (hazard ratio = 0.49; P < 0.001). Besides, thermal ablation did not increase the risk of major complication (odds ratio = 0.75; P = 0.252).

CONCLUSION

The present meta-analysis based on these studies in China suggested that thermal ablation is a promising technique to provide better disease response and survival outcomes for patients with lung malignancy. Thermal ablation is worth further promotion in treating lung malignancy and application in clinical practice.

Image-guided percutaneous ablation for lung malignancies

Image-guided percutaneous lung ablation has proven to be an alternative and effective strategy in the treatment of lung cancer and other lung malignancies. Radiofrequency ablation, microwave ablation, and cryoablation are widely used ablation modalities in clinical practice that can be performed along or combined with other treatment modalities. In this context, this article will review the application of different ablation strategies in lung malignancies.

Microwave ablation plus camrelizumab monotherapy or combination therapy in non-small cell lung cancer

Purpose

Immunotherapy has become widely applied in non-small cell lung cancer (NSCLC) patients. However, the relatively low response rate of immunotherapy monotherapy restricts its application. Combination therapy improves the response rate and prolongs patient survival; however, adverse events (AEs) associated with immunotherapies increase with combination therapy. Therefore, exploring combination regimens with equal efficacy and fewer AEs is urgently required. The aim of this study was to evaluate the efficacy and safety of microwave ablation (MWA) plus camrelizumab monotherapy or combination therapy in NSCLC.

Materials and methods

Patients with pathologically confirmed, epidermal growth factor receptor/anaplastic lymphoma kinase-wild-type NSCLC were retrospectively enrolled in this study. Patients underwent MWA to the pulmonary lesions first, followed by camrelizumab monotherapy or combination therapy 5–7 days later. Camrelizumab was administered with the dose of 200 mg every 2 to 3 weeks. Treatment was continued until disease progression or intolerable toxicities. The technical success and technique efficacy of ablation, objective response rate (ORR), progression-free survival (PFS), overall survival (OS), complications of ablation, and AEs were recorded.

Results

From January 1, 2019 to December 31, 2021, a total of 77 patients underwent MWA and camrelizumab monotherapy or combination therapy. Technical success was achieved in all patients (100%), and the technique efficacy was 97.4%. The ORR was 29.9%. The PFS and OS were 11.8 months (95% confidence interval, 9.5–14.1) and not reached, respectively. Smoking history and response to camrelizumab were correlated with PFS, and response to camrelizumab was correlated with OS in both the univariate and multivariate analyses. No periprocedural deaths due to ablation were observed. Complications were observed in 33 patients (42.9%). Major complications included pneumothorax (18.2%), pleural effusion (11.7%), pneumonia (5.2%), bronchopleural fistula (2.6%), and hemoptysis (1.3%). Grade 3 or higher AEs of camrelizumab, including reactive capillary endothelial proliferation, fatigue, pneumonia, edema, and fever, were observed in 10.4%, 6.5%, 5.2%, 2.6%, and 2.6% of patients, respectively.

Conclusion

MWA combined with camrelizumab monotherapy or combination therapy is effective and safe for the treatment of NSCLC.

Survival benefit of thermal ablation therapy for patients with stage II-III non-small cell lung cancer: A propensity-matched analysis

Background

Thermal ablation (TA) is considered a safe alternative to surgical resection for the treatment of non-small cell lung cancer (NSCLC). While previous studies have shown that TA is beneficial for stage I NSCLC patients, however, few have reported on TA efficacy in patients with stage II-III NSCLC. The current study investigated the impact of TA on the overall survival (OS) and cancer-specific survival (CSS) of patients with stage II-III NSCLC.

Methods

Data on patients with stage II-III NSCLC who did not undergo surgical resection between 2004 and 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM), Kaplan-Meier survival curves, and Cox regression were used for statistical analyses.

Results

A total of 57,959 stage II-III NSCLC patients who did not undergo surgical resection were included in this study, 261 of whom received TA. Overall, TA was associated with a longer OS (p = 0.035) and CSS (p = 0.005) than non-ablation. After 1:3 PSM, 252 patients receiving TA and 732 patients not receiving ablation were enrolled in the matched cohort. The OS (p = 0.047) and CSS (p = 0.029) remained higher in the TA group than in the non-ablation group after PSM. Cox regression analysis showed that age, sex, primary tumor site, pathological type, tumor size, radiotherapy, chemotherapy, and thermal ablation were independently associated with OS and CSS (p <0.05). Subgroup analysis found that the advantages of TA were more pronounced among individuals ≥70 years of age, with tumor size ≤3.0 cm, or who did not receive radiotherapy.

Conclusion

TA could be an effective alternative treatment for stage II-III NSCLC patients unsuitable for surgical resection, particularly those ≥70 years of age, with tumor size ≤3.0 cm, or who have not received radiotherapy.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Local ablative therapies in oligometastatic NSCLC-upfront or outback?-a narrative review

Patients with oligometastatic (OM) non-small cell lung cancer (NSCLC) have favorable outcomes compared to patients presenting with diffuse metastatic disease. Recent randomized trials have demonstrated safety and efficacy signals for local ablative therapies with radiotherapy, surgery, or radiofrequency ablation for OM-NSCLC patients alongside systemic therapies. However, it remains unclear whether local ablative therapy (LAT) should be offered either upfront preceding systemic therapies or following initial systemic therapies as local consolidative therapy (LCT). Establishing optimal timing of RT and systemic therapy combinations is essential to maximize efficacy while maintaining safety. Most published randomized trial evidence surrounding the benefits of LAT and systemic therapies were generated from OM-NSCLC patients receiving cytotoxic chemotherapy agents. With increasing use of novel agents such as targeted therapies (i.e., tyrosine kinase inhibitors) and immune checkpoint inhibitors in management of metastatic NSCLC patients, LAT timing may need to be modulated based on the use of specific agents. This narrative review will discuss the current evidence on either upfront LAT or LCT for OM-NSCLC based on published trials and cohort studies. We briefly explored the possible biological mechanisms of the potential clinical advantages of either approach. This review also summarized the ongoing trials incorporating both upfront LAT and LCT, and considerations for future LAT strategies.

Survival prediction for non-small cell lung cancer patients treated with CT-guided microwave ablation: development of a prognostic nomogram

OBJECTIVES

To explore the outcomes of CT-guided percutaneous microwave ablation (MWA) in non-small cell lung cancer (NSCLC) patients, and then develop an effective nomogram to predict the survival.

METHODS

NSCLC patients treated with MWA were randomly allocated to either the training cohort or the validation cohort (3:1). The primary outcome measurement was overall survival (OS), whose predictors were identified by univariate and multivariate analyses in the training cohort. Then, a predictive nomogram was developed to predict the OS, with the predictive accuracy evaluated by C-statistic and receiver operating characteristic in both the training and validation cohorts.

RESULTS

A total of 234 patients (training cohort: n = 176; validation cohort: n = 58) and 271 tumors with a median OS of 17.0 ± 12.2 months were included. The predictors selected into the nomogram included tumor diameter (hazard ratio [HR], 2.12; 95% confidence interval [CI], 1.37-3.30; p < 0.001), extrapulmonary metastases (HR, 1.77; 95% CI, 1.06-2.95; p = 0.030), tumor stage (HR, 1.38; 95% CI, 1.07-1.79; p = 0.013), tumor type (HR, 2.00; 95% CI, 1.48-2.72; p < 0.001) and post-MWA TKIs (HR, 0.55; 95% CI, 0.34-0.89; p < 0.001), based on the results of univariate and multivariate analyses. The C-statistic showed good predictive performance, with a C-statistic of 0.838 (95% CI, 0.779-0.897) internally and 0.808 (95% CI, 0.695-0.920) externally (training cohort and validation cohort, respectively).

CONCLUSIONS

The nomogram was effective in predicting the OS in NSCLC patients treated with MWA, and could be applied to identify patients who may benefit most from MWA and be helpful for clinical decision making.

Clinical efficacy of systemic chemotherapy combined with radiofrequency ablation and microwave ablation for lung cancer: a comparative study

OBJECTIVE

Local thermal ablation, a minimally invasive technique, has been widely used in clinical treatment of lung cancer. This study aimed to discuss the clinical efficacy of systemic chemotherapy combined with radiofrequency ablation (RFA) versus systemic chemotherapy combined with microwave ablation (MWA) in treating lung cancer.

METHODS

A retrospective analysis involving 124 lung cancer patients, who received RFA (n = 68) and MWA (n = 56) combined with systemic chemotherapy in Cangzhou People's Hospital from August 2017 to December 2019, was conducted. Before comparative analysis for therapeutic efficacy, the two groups of patients were matched with propensity score matching method at a ratio of 1:1. Indicators including progression-free survival (PFS), overall survival (OS), short-term efficacy, tumor marker level, local tumor control rate, and postoperative complications were comparatively analyzed.

RESULTS

There was no statistical difference in disease control rate and objective response rate (90.6% and 78.1% vs 93.8% and 84.4%) between RFA group and MWA group. The incidence of complications was 12.5% in RFA group and 18.8% in MWA group with no statistically significant difference. In addition, the local tumor control rate in MWA group (90.6%) was significantly higher than that in RFA group (78.1%). Regarding survival, a statistically significant difference was observed in median PFS of RFA and MWA groups (9.2 months vs 10.4 months, p < 0.05), while OS in two groups slightly varied.

CONCLUSION

MWA was superior to RFA over local tumor control rate and PFS and showed great potential in lung cancer ablation treatment.

[Advances and Challenges of Local Thermal Ablation in Non-small Cell Lung Cancer]

非小细胞肺癌（non-small cell lung cancer, NSCLC）是原发性肺癌的主要类型，手术切除、放化疗、靶向治疗及免疫治疗等是其主要的治疗模式。近年来，热消融在各期NSCLC的临床应用中受到越来越多的关注。热消融作为一种安全、高效的局部治疗手段，合理的临床应用可以给NSCLC患者带来更多的临床获益。然而其在NSCLC中的应用仍然存在许多尚待研究探讨的问题。本文对近年来热消融在NSCLC中的应用现状作以综述，旨在探讨目前存在的争议问题和未来研究方向。

Microwave ablation plus chemotherapy versus chemotherapy in advanced non-small cell lung cancer: a multicenter, randomized, controlled, phase III clinical trial

OBJECTIVES

This prospective trial was performed to verify whether microwave ablation (MWA) in combination with chemotherapy could provide superior survival benefit compared with chemotherapy alone.

MATERIALS AND METHODS

From March 1, 2015, to June 20, 2017, treatment-naïve patients with pathologically verified advanced or recurrent non-small cell lung cancer (NSCLC) were randomly assigned to MWA plus chemotherapy group or chemotherapy group. The primary endpoint was progression-free survival (PFS), while the secondary endpoints included overall survival (OS), time to local progression (TTLP), and objective response rate (ORR). The complications and adverse events were also reported.

RESULTS

A total of 293 patients were randomly assigned into the two groups. One hundred forty-eight patients with 117 stage IV tumors were included in the MWA plus chemotherapy group. One hundred forty-five patients with 113 stage IV tumors were included in the chemotherapy group. The median follow-up period was 13.1 months and 12.4 months, respectively. Median PFS was 10.3 months (95% CI 8.0-13.0) in the MWA plus chemotherapy group and 4.9 months (95% CI 4.2-5.7) in the chemotherapy group (HR = 0.44, 95% CI 0.28-0.53; p < 0.0001). Median OS was not reached in the MWA plus chemotherapy group and 12.6 months (95% CI 10.6-14.6) in the chemotherapy group (HR = 0.38, 95% CI 0.27-0.53; p < 0.0001) using Kaplan-Meier analyses with log-rank test. The median TTLP was 24.5 months, and the ORR was 32% in both groups. The adverse event rate was not significantly different in the two groups.

CONCLUSIONS

In patients with advanced NSCLC, longer PFS and OS can be achieved with the treatment of combined MWA and chemotherapy than chemotherapy alone.

KEY POINTS

• Patients treated with MWA plus chemotherapy had superior PFS and OS over those treated with chemotherapy alone. • The ORR of patients treated with MWA plus chemotherapy was similar to that of those treated with chemotherapy alone. • Complications associated with MWA were common but tolerable and manageable.

Efficacy and safety of microwave ablation in the treatment of patients with oligometastatic non-small-cell lung cancer: a retrospective study

Purpose: Patients with oligometastatic non-small-cell lung cancer (NSCLC) benefit from local control treatments such as surgery or irradiation. The efficacy and safety of microwave ablation (MWA) in these patients was unknown. Material and methods: Between January 2011 and April 2018, eligible patients were retrospectively enrolled. MWA was conducted for both primary lesions and metastatic lesions in patients with synchronous metastases and in metastatic lesions for patients with metachronous metastases. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were overall survival (OS), technical success, technique efficacy, and complications. Results: Seventy-nine patients with 103 oligometastatic lesions were enrolled. A total of 20 primary lesions and 96 metastatic lesions were treated with MWA during 101 procedures. Technical success was achieved in all patients. Technique efficacy was achieved in 72 patients (91.1%). The median PFS and OS were 14.0 and 47.8 months, respectively. Forty-four patients (55.7%) developed complications with 21 (29.6%) of these patients developing major complications. All complications were resolved via appropriate medical treatments, and no MWA-related deaths occurred. Conclusion: MWA was safe and effective for patients with oligometastatic NSCLC.

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.

Microwave ablation or plus monochemotherapy in elderly advanced non-small-cell lung cancer patients

OBJECTIVE

To evaluate the efficacy of microwave ablation (MWA) and MWA plus monochemotherapy in elderly patients with advanced non-small-cell lung cancer (NSCLC).

MATERIAL AND METHODS

Patients with advanced NSCLC aged ≥70 years were retrospectively enrolled. MWA was performed at the primary tumor site. The end points included progression-free survival (PFS), response to MWA and overall survival (OS).

RESULTS

Fifty-four patients were enrolled; of these, 36 received monochemotherapy. Complete ablation was achieved in 42 patients (77.8%). The median PFS and OS were 4.9 months and 21.8 months, respectively. Univariate analyses showed that female patients had superior PFS (31.9 months [95% confidence interval (CI): 0.8-63.0]) vs. 5.0 months in male patients (95% CI: 2.0-8.0), p = .002). Female sex was associated with better OS (not reached vs. 10.8 months, 95% CI: 9.3-12.3, p = .003). Moreover, patients with primary tumor size <3.5 cm had better OS than those with tumor size ≥3.5 cm (not reached vs. 10.9 months, 95% CI: 8.2-13.6, p = .006). Multivariate analyses showed that no characteristics were independent prognostic factors of PFS, but sex and primary tumor size were independent prognostic factors of OS.

CONCLUSION

MWA was effective in the treatment of elderly patients with advanced NSCLC.

Microwave ablation combined with chemotherapy improved progression free survival of IV stage lung adenocarcinoma patients compared with chemotherapy alone

Background

Microwave ablation (MWA) has recently become an established treatment option for topical therapy of lung cancer patients. In this study, we evaluated whether MWA combined with chemotherapy could improve progression‐free survival (PFS) of patients with stage IV lung adenocarcinoma compared with chemotherapy alone.

Methods

A total of 49 patients were enrolled into the study; 21 patients accepted MWA therapy combined with chemotherapy, 28 patients accepted only chemotherapy. Enumeration data were analyzed using χ2 test or Fisher's exact probability test and univariate analysis was analyzed using Kaplan–Meier survival curves. Multivariate analysis was carried out with the Cox proportional hazard model.

Results

The treatment regimen was not correlated with clinical features of the patients, which included gender, age, smoking history, tumor site, tumor size and Eastern Cooperative Oncology Group (ECOG). The patients’ 3‐year overall survival (OS) was 12.5%, and median survival time was 19.3 months. The median PFS was 6.1 months and the 1‐year PFS was 0.0%. The PFS was significantly associated with tumor size (P < 0.05), ECOG (P < 0.01) and treatment regimen (P < 0.01). The median time to local progression (TTLP) was 8.4 months and the 3‐year TTLP was 2.0%. The TTLP was significantly associated with tumor size (P < 0.05) and treatment regimen (P < 0.01). Cox multivariate regression demonstrated that MWA combined with chemotherapy was the independent factor for both the PFS and TTLP.

Conclusion

MWA, as a topical treatment method, when combined with chemotherapy improved the PFS and TTLP of patients with stage IV lung adenocarcinoma.

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.

Programmed death-ligand 1 expression and CD8+ tumor-infiltrating lymphocytes in advanced non-small cell lung cancer treated with microwave ablation and chemotherapy

BACKGROUND

Programmed death-ligand 1 (PD-L1) and CD8+ tumor-infiltrating lymphocytes (TILs) were associated with non-small cell lung cancer (NSCLC). We conducted this study to evaluate the correlation between PD-L1 or CD8+ TILs expression and MWA or survival in advanced NSCLC patients treated with microwave ablation (MWA) plus chemotherapy.

METHODS

Previously untreated, pathologically verified advanced NSCLC patients with adequate tissues for the analysis of PD-L1 expression and the presence of CD8+ TILs were retrospectively enrolled. None of the patients had sensitive mutations, and therefore, they were treated with MWA of the primary tumors followed by chemotherapy.

RESULTS

A total of 51 patients were enrolled. PD-L1 expression and the presence of CD8+ TILs were identified in 31 (60.8%) and 9 (17.6%) patients, respectively. PD-L1 expression and CD8+ TILs had no correlation with baseline characteristics, the response to chemotherapy or MWA. Patients with PD-L1 expression had similar progression-free survival (PFS: 7.9 months for PD-L1-positive vs. 5.8 months for PD-L1-negative; p = .660) and overall survival (OS: 18.7 months for PD-L1-positive vs. 15.2 months for PD-L1-negative; p = .901). Patients with CD8+ TIL expression did not show superior PFS (CD8+ TIL vs. CD8- TIL, 8.0 vs. 6.2 months, p = .435) or OS (CD8+ TIL vs. CD8- TIL, 20.5 vs. 16.9 months, p = .653).

CONCLUSION

PD-L1 expression and the presence of CD8+ TILs could predict neither the patients' response to chemotherapy or MWA nor survival in advanced NSCLC patients treated with MWA plus chemotherapy.

Microwave ablation followed by immediate biopsy in the treatment of non-small cell lung cancer

BACKGROUND

To evaluate the efficacy and safety of microwave ablation (MWA) followed by immediate biopsy in the treatment of non-small cell lung cancer (NSCLC) and to clarify whether pathology changes can predict treatment responses and patient survival.

METHODS

Patients with pathologically confirmed NSCLC pre-ablation were treated with MWA, and immediate biopsy was carried out right after ablation in one procedure. Pathology changes were categorized according to the pre- and postablation pathology: Group A, same histology type; Group B, paired histology type with burning degeneration; Group C, no definite histology type; Group D, no definite cancer cells. The internal correlations between pathology changes and baseline characteristics, responses to MWA and survival were evaluated.

RESULTS

A total of 68 patients were enrolled in the study, of which 19, 28, 11 and 10 patients were classified into Group A, Group B, Group C and Group D, respectively. In total, 85.3 and 69.1% patients were diagnosed with malignant tumors and the same pathology type, respectively. No significant difference in clinical-pathologic characteristics or response to MWA between the groups was observed. Upon combining Groups A, B and C, Group D exhibited longer progression-free survival (PFS) (Groups A + B + C versus Group D, 11.7 months, 95% CI 9.6-13.7 versus 26.6 months, 95% CI 19.0-34.2, p = .253) and overall survival (OS) (15.9 months, 95% CI 14.2-17.5, versus 29.8 months, 95% CI, 24.3-35.3, p = .395), although no significant differences were observed. Complications were identified in 63 (92.6%), of which 17 (25.0%) patients had major complications.

CONCLUSIONS

Immediate biopsy post-MWA can distinguish cancer cells or histology types in most cases of NSCLC. However, pathology changes pre- and postablation could not predict the response to MWA and patient survival.

The safety and efficacy of microwave ablation for the treatment of CRC pulmonary metastases

PURPOSE

Microwave ablation (MWA) is a recently developed thermal ablation technique that has been used for the treatment of different types of tumours. In the present study, we retrospectively evaluated the safety and efficacy of CT-guided percutaneous MWA for the treatment of colorectal cancer (CRC) pulmonary metastases.

MATERIALS AND METHODS

From June 2010 to June 2015, 48 unresectable lesions in 32 patients with CRC pulmonary metastases were subjected to CT-guided MWA. Imaging follow-up was with contrast-enhanced CT and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT.

RESULTS

Oncologic imaging showed that 42 (87.5%) of the 48 lesions in the 32 patients were completely ablated. Needle track metastatic seeding was not found, and no patient deaths occurred within 30 d after ablation. The mean hospital stay was 3 d (range, 2-7 d). Pneumothorax was the most frequent complication and occurred in 6 (12.5%) of the 48 lesions. The median survival time was 31 months (95% CI: 15.4-46.6). The 1-, 2- and 3-year survival rates were 79.5%, 63.1% and 44.4%, respectively. Univariate Cox regression analysis showed that tumour size, disease-free interval (DFI) and number of tumours were significantly related to the overall survival time (p = .007, p = .022 and p = .030, respectively). Multivariate analysis showed that tumour size was an independent prognostic factor for survival (p = .017).

CONCLUSION

CT-guided percutaneous MWA is a safe and effective minimally invasive method for treating CRC pulmonary metastases.

Microwave ablation combined with EGFR-TKIs versus only EGFR-TKIs in advanced NSCLC patients with EGFR-sensitive mutations

We conducted this retrospective study to investigate whether microwave ablation (MWA) of primary tumor sites plus epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) could improve survival in advanced non small cell lung cancer (NSCLC) with EGFR mutations. MWA was conducted at the primary tumor sites, followed by EGFR-TKIs in the MWA plus EGFR-TKIs group. EGFR-TKIs were administered until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS) and objective response rate (ORR). A total of 58 patients were recruited, including 34 in the MWA plus EGFR-TKIs group and 24 in the EGFR-TKIs group. No significant difference in ORR was observed with MWA treatment (61.8% vs. 45.8%, p = 0.230). Patients treated with MWA plus EGFR-TKIs failed to show superior survival in either PFS (13.2 months vs. 11.6 months, p = 0.640) or OS (39.8 months vs. 20.4 months, p = 0.288). MWA was not an independent prognostic factor for PFS or OS. MWA of primary tumor sites plus EGFR-TKIs demonstrated no survival advantage compared with EGFR-TKIs alone in advanced NSCLC patients with EGFR sensitive mutations. MWA should not be recommended for unselected patients with EGFR-sensitive mutations.

Status and advancement of microwave ablation in China

Tumour ablation is defined as the direct application of chemical or thermal therapy to eradicate or substantially destroy a tumour. Currently, minimally invasive ablation techniques are available for the local destruction of focal tumours in multiple organ sites. Microwave ablation (MWA) is premised on the biological response of solid tumours to tissue hyperthermia, and it is a relatively low-risk procedure. Due to several advantages of MWA, including higher thermal efficiency, higher capability for coagulating blood vessels, faster ablation time and the simultaneous application of multiple antennae, MWA could be a promising minimally invasive ablation technique for the treatment of solid tumours. Therefore, the use of MWA has developed rapidly in China during the last decade. Many successful studies have been performed, and widespread use has been achieved for multiple types of tumours in China, especially for liver cancer. This review will describe the state-of-the-art of MWA in China, including the development of MWA equipment and its application in the treatment of multiple types of tumours.

Treatment of lung tumours with high-energy microwave ablation: a single-centre experience

The purpose of our study is to report safety, technical success, effectiveness, local progression-free survival (LPFS) and overall survival of percutaneous microwave ablation (MWA) to treat lung tumours unsuitable for surgery. Nineteen patients with thirty-one tumours (mean diameter 2.4 cm) underwent percutaneous MWA in 28 sessions. Microwave ablation was carried out using a 2450-MHz generator (Emprint/Covidien, Boulder, CO, USA). Procedures were performed under cone-beam CT (CBCT) and under fluoro-CT (one session) guidance. Safety, technical success, effectiveness, LPFS and overall survival (OS) were evaluated. Safety was defined as the frequency of major and minor complications. The efficacy was evaluated on the basis of imaging characteristics, using RECIST criteria. CT follow-up was performed at 1, 3 and 6 months and yearly. LPFS was defined as the interval between MWA treatment and evidence of local recurrence, if there was any. OS was defined as the percentage of patients who were still alive. We registered one major complication (purulent hydro-pneumothorax). Minor complications were spontaneously resolved (pneumothorax and perilesional haemorrhagic effusion). Technical success was 100%. Residual disease was registered in two cases, one of whom was retreated. Complete ablation was obtained in the remaining cases (90.3%). During available follow-up (mean 9.6 months), 9/31 tumours demonstrated local recurrence. Five tumours were retreated, and none of them presented residual disease during follow-up (LPFS 22.6%). Overall survival was 93.8%. Percutaneous high-energy MWA is a safe, effective and confident technique to treat lung tumours not suitable for surgery.

Short-Term Outcomes and Safety of Computed Tomography-Guided Percutaneous Microwave Ablation of Solitary Adrenal Metastasis from Lung Cancer: A Multi-Center Retrospective Study

Objective

To retrospectively evaluate the short-term outcomes and safety of computed tomography (CT)-guided percutaneous microwave ablation (MWA) of solitary adrenal metastasis from lung cancer.

Materials and Methods

From May 2010 to April 2014, 31 patients with unilateral adrenal metastasis from lung cancer who were treated with CT-guided percutaneous MWA were enrolled. This study was conducted with approval from local Institutional Review Board. Clinical outcomes and complications of MWA were assessed.

Results

Their tumors ranged from 1.5 to 5.4 cm in diameter. After a median follow-up period of 11.1 months, primary efficacy rate was 90.3% (28/31). Local tumor progression was detected in 7 (22.6%) of 31 cases. Their median overall survival time was 12 months. The 1-year overall survival rate was 44.3%. Median local tumor progression-free survival time was 9 months. Local tumor progression-free survival rate was 77.4%. Of 36 MWA sessions, two (5.6%) had major complications (hypertensive crisis).

Conclusion

CT-guided percutaneous MWA may be fairly safe and effective for treating solitary adrenal metastasis from lung cancer.

Local Efficacy and Survival after Microwave Ablation of Lung Tumors: A Retrospective Study in 183 Patients

PURPOSE

To retrospectively evaluate local efficacy and survival after microwave (MW) ablation of lung tumors and identify predictors of prognosis.

MATERIALS AND METHODS

Data from 183 consecutive patients (67 women; mean age, 61.5 y ± 13.4) with lung tumors who had undergone 203 lung MW ablation sessions from January 2011 to May 2013 were assessed. The χ² test, independent-samples t test, Kaplan-Meier analysis, and Cox regression model analysis were used to estimate survival rates and evaluate significance of factors affecting rates of incomplete ablation, local progression, remote progression-free survival (RPFS), and cancer-specific survival (CSS).

RESULTS

Technical success rate was 100%. Incomplete ablation rate after 183 first MW ablations was 14.2% (26 of 183); maximum diameter of target tumors (P = .00001) was associated with incomplete ablation on univariate analysis. The local progression rate was 19.1% (35 of 183); emphysema (P = .020) and maximum diameter of target tumor (P = .000003) were associated with local progression. Median and 4-year RPFS were 15.0 months (95% confidence interval [CI], 11.1-18.9 mo) and 23.8%, respectively. Tumor stage (P < .01) and incomplete ablation (P = .002) were independent predictors of RPFS. Median and 4-year CSS were 24.9 months (95% CI, 19.9-29.9 mo) and 31.1%, respectively. Median and 4-year overall survival were 23.7 months (95% CI, 20.6-26.8 mo) and 29.6%, respectively. Tumor stage (P < .01) and maximum diameter (P = .009) were independent risk factors for CSS.

CONCLUSIONS

MW ablation is effective for lung tumors, especially small lesions of early-stage primary lung cancer and solitary lung metastasis.

Local microwave ablation with continued EGFR tyrosine kinase inhibitor as a treatment strategy in advanced non-small cell lung cancers that developed extra-central nervous system oligoprogressive disease during EGFR tyrosine kinase inhibitor treatment: A pilot study

The non-small cell lung cancer (NSCLC) patients that experienced good clinical response to epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKIs) will ultimately develop acquired resistance. This retrospective study was performed to explore the potential survival benefit of microwave ablation (MWA) therapy in epidermal growth factor receptor (EGFR)-mutant NSCLC that developed extra-central nervous system (CNS) oligoprogressive disease during TKI treatment.We retrospectively analyzed 54 NSCLC patients with EGFR mutations who showed a clinical benefit from initial EGFR-TKI therapy and developed extra-CNS oligoprogressive disease at our institutions. Twenty eight patients received MWA as a local therapy for the metastatic sites and continued on the same TKIs (MWA group). The following 26 patients received systemic chemotherapy after progression (chemotherapy group). The progression-free survival (PFS1) was calculated from initiation of targeted therapy to first progression. Progression-free survival (PFS2) was defined from first progression to second progression after MWA or chemotherapy. Overall survival (OS) was calculated from the time of diagnosis to the date of last follow-up or death.The median PFS1 for both groups was similar (median 12.6 vs. 12.9 months, HR 0.63). However, the MWA group patients had a significantly longer PFS2 (median 8.8 vs. 5.8 months, hazards ratio [HR] 0.357) and better OS (median 27.7 vs. 20.0, HR 0.238) in comparison with chemotherapy group. Multivariate analysis and the internal validation identified MWA as the main favorable prognostic factor for PFS2 and OS. In the MWA group, the median PFS2 for complete ablation was significantly longer than that for incomplete ablation (11 vs. 4.2 months, HR 0.29, P < 0.05).MWA with continued EGFR inhibition might be associated with favorable progression-free survival (PFS) and OS in patients with extra-CNS oligometastatic disease. MWA as a local therapy for extra-CNS oligometastatic disease should be considered for NSCLC with acquired resistance to EGFR-TKIs.