Chinese expert consensus workshop report: Guidelines for thermal ablation of primary and metastatic lung tumors

Risk prediction of intraoperative pain in percutaneous microwave ablation of lung tumors under CT guidance

OBJECTIVES

To evaluate the effect of intraoperative pain in microwave ablation of lung tumors (MWALT) on local efficacy and establish the pain risk prediction model.

METHODS

It was a retrospectively study. Consecutive patients with MWALT from September 2017 to December 2020 were divided into mild and severe pain groups. Local efficacy was evaluated by comparing technical success, technical effectiveness, and local progression-free survival (LPFS) in two groups. All cases were randomly allocated into training and validation cohorts at a ratio of 7:3. A nomogram model was established using predictors identified by logistics regression in training dataset. The calibration curves, C-statistic, and decision curve analysis (DCA) were used to evaluate the accuracy, ability, and clinical value of the nomogram.

RESULTS

A total of 263 patients (mild pain group: n = 126; severe pain group: n = 137) were included in the study. Technical success rate and technical effectiveness rate were 100% and 99.2% in the mild pain group and 98.5% and 97.8% in the severe pain group. LPFS rates at 12 and 24 months were 97.6% and 87.6% in the mild pain group and 91.9% and 79.3% in the severe pain group (p = 0.034; HR: 1.90). The nomogram was established based on three predictors: depth of nodule, puncture depth, and multi-antenna. The prediction ability and accuracy were verified by C-statistic and calibration curve. DCA curve suggested the proposed prediction model was clinically useful.

CONCLUSIONS

Severe intraoperative pain in MWALT reduced the local efficacy. An established prediction model could accurately predict severe pain and assist physicians in choosing a suitable anesthesia type.

CLINICAL RELEVANCE STATEMENT

This study firstly provides a prediction model for the risk of severe intraoperative pain in MWALT. Physicians can choose a suitable anesthesia type based on pain risk, in order to improve patients' tolerance as well as local efficacy of MWALT.

KEY POINTS

• The severe intraoperative pain in MWALT reduced the local efficacy. • Predictors of severe intraoperative pain in MWALT were the depth of nodule, puncture depth, and multi-antenna. • The prediction model established in this study can accurately predict the risk of severe pain in MWALT and assist physicians in choosing a suitable anesthesia type.

Microwave ablation therapy assisted by artificial pneumothorax and artificial hydrothorax for lung cancer adjacent to the vital organs

Objectives

This study aimed to investigate the technical methods and safety of artificial pneumothorax and artificial hydrothorax in the treatment of lung cancer adjacent to vital organs by CT-guided microwave ablation.

Subjects and Methods

Three of the six patients were men and three were women, with a mean age of 66.0 years (range 47–78 years). There patients had primary pulmonary adenocarcinoma, one had lung metastasis from liver cancer, one had lung metastasis from colon cancer, and one had lung metastasis from bladder cancer. There were four patients with a single lesion, one with two lesions, and one with three lesions. The nine lesions had a mean diameter of 1.1 cm (range 0.4–1.9). In three patients, the lung cancer was adjacent to the heart, and in the remaining three, it was close to the superior mediastinum. Six patients were diagnosed with lung cancers or lung metastases and received radical treatment with microwave ablation (MWA) assisted by artificial pneumothorax and artificial hydrothorax in our hospital. Postoperative complications were observed and recorded; follow-up was followed to evaluate the therapeutic effect.

Results

The artificial pneumothorax and artificial hydrothorax were successfully created in all six patients. A suitable path for ablation needle insertion was also successfully established, and microwave ablation therapy was carried out. 2 patients developed pneumothorax after operation; no serious complications such as operation-related death, hemothorax, air embolism and infection occurred.Moreover, 4–6 weeks later, an enhanced CT re-examination revealed no local recurrence or metastasis, and the rate of complete ablation was 100%.

Conclusions

Microwave ablation, assisted by artificial pneumothorax, artificial hydrothorax, is a safe and effective minimally invasive method for treating lung cancer adjacent to the vital organs, and optimizing the path of the ablation needle and broadening the indications of the ablation therapy

Microwave ablation with local pleural anesthesia for subpleural pulmonary nodules: our experience

Objectives

To explore the efficacy and safety of local pleural anesthesia (LPA) for relieving pain during microwave ablation (MWA) of pulmonary nodules in the subpleural regions.

Materials and Methods

From June 2019 to December 2021, 88 patients with 97 subpleural nodules underwent percutaneous CT-guided MWA. Patients were divided into two groups according to whether LPA was applied; 53 patients with local pleural anesthesia during MWA; and 35 patients with MWA without LPA. The differences in technical success, pre-and post- and intra-operative visual analog scale (VAS) pain scores, complications of the procedure, and local progression-free survival (LPFS) between the two groups were assessed. Thus, to evaluate the efficacy and safety of MWA combined with LPA for treating subpleural nodules.

Results

In this study, the procedures in all patients of both groups achieved technical success according to pre-operative planning. There was no statistically significant difference in the pre-operative VAS pain scores between the two groups. Intra-operative VAS scores were significantly higher in the non-LPA (NLPA) group than in the LPA group. They remained significantly higher in the NLPA group than in the LPA group during the short postoperative period. Analgesics were used more in the NLPA group than in the LPA group intra- and postoperatively, with a statistically significant difference, especially during the MWA procedures. The overall LPFS rates were 100%, 98.333%, 98.333%, and 98.333% at 1, 3, 6, and 12 months postoperatively in the LPA group and 100%, 97.297%, 94.595%, and 94.595% postoperatively in the NLPA group, respectively. Tumor recurrence occurred in one and two patients with lung adenocarcinoma in the LPA and NLPA groups. The incidence of pneumothorax was significantly higher in the NLPA group (25,714%, 9/35) than in the LPA group (15.094%, 8/53), and there were three cases of pleural effusion (blood collection) and one case of pulmonary hemorrhage in the NLPA group.

Conclusion

Percutaneous CT-guided MWA is a safe and effective treatment for subpleural pulmonary nodules. Applying a combined LPA technique can reduce the patient’s pain and complications during and after the MWA. The long-term efficacy must be verified in more patients and a longer follow-up.

Review of clinical tumor ablation advance in Asia

Tumor ablation has been widely applied in Asia, accounting for 44.65% of clinical studies worldwide. We reviewed 5853 clinical studies to provide insight on the advance of tumor ablation in Asia chronologically and geographically among different techniques and organs. Since 1998, tumor ablation application has dramatically evolved in Asia. All kinds of ablation techniques, including percutaneous ethanol injection (PEI), radiofrequency ablation (RFA), microwave ablation (MWA), laser ablation (LA), cryoablation (CA), high-intensity focused ultrasound (HIFU), and irreversible electroporation (IRE), have been applied, with the first application of PEI and the most popular application of RFA. Twenty-five countries and one district in Asia have applied tumor ablation in various organs, including liver, lung, uterus, thyroid, kidney, pancreas, bone, prostate, breast, adrenal gland, lymph node parathyroid, esophagus, etc. Due to the high incidence of tumors as well as advanced economy and technology, East Asia accounted for 93.87% of studies, led by China (45.00%), Japan (32.72%), South Korea (12.10%), and Taiwan (4.03%). With the enrichment of evidence from large-scale multicenter and randomized control studies, China and South Korea have issued several guidelines on tumor ablation for liver, lung, and thyroid, which provided recommendations for global standardization of tumor ablation techniques. Therefore, Asia has made active contribution to global tumor ablation therapy.KeypointsKey point 1: Asia accounted for 44.65% of clinical studies worldwide on tumor ablation.Key point 2: Twenty-five countries and one district in Asia have used tumor ablation in various organs, and East Asia accounted for 93.87% of studies, led by China (45.00%), Japan (32.72%), South Korea (12.10%), and Taiwan (4.03%).Key point 3: China and South Korea have issued several guidelines on tumor ablation for liver, lung, and thyroid, which provided recommendations for global standardization of tumor ablation techniques.

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.

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.

Salvage treatment of NSCLC recurrence after first-line chemotherapy failure: Iodine-125 seed brachytherapy or microwave ablation?

Background

Salvage treatments for recurrent NSCLC after first‐line chemotherapy remain challenging. This study was conducted to evaluate the clinical value of microwave ablation (MWA) and iodine‐125 brachytherapy, including overall survival (OS), disease free survival (DFS), local control, hospital stay, and health economics.

Methods

The data of 51 and 32 patients who were treated with MWA and brachytherapy was retrospectively analyzed. The number of lesions was limited up to two, with a diameter <4 cm and patients diagnosed with unilateral lung disease. Peripheral tumors were treated with MWA, while lesions close to the hilum were treated with brachytherapy. Contrast‐enhanced CT, blood cell count, coagulation function, liver & kidney function and tumor markers were performed for two years, with complications calculated. OS, DFS, local control rate, toxicity, hospital stay and expense were recorded.

Results

The one and two‐year OS rates were 96.08% and 92.16% versus 96.88% and 90.62% in the MWA and brachytherapy groups, respectively. The one and two‐year DFS rates were 92.16% and 76.47% versus 93.75% and 78.13%, respectively. No significant differences were observed in log‐rank analysis between the groups. Local control rates at six and 12 months were 100% and 96.08% versus 100% and 96.88%, while incidences of pleural effusion were 3.92% and 3.13%, respectively (P < 0.05). Medical cost was 3356.73 ± 206.87 and 6714.28 ± 35.43 U.S. dollars (P = 0.014).

Conclusion

MWA and brachytherapy are effective and safe options for the treatment of NSCLC recurrence after first‐line chemotherapy. Which modality should be considered is dependent upon tumor location, tumor size and experience of specialists.

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.

Comparison between computed tomography-guided percutaneous microwave ablation and thoracoscopic lobectomy for stage I non-small cell lung cancer

Background

The study was conducted to investigate the effectiveness and cost of computed tomography (CT)‐guided percutaneous microwave ablation (MWA) and thoracoscopic lobectomy for stage I non‐small cell lung cancer (NSCLC).

Methods

We retrospectively analyzed the data of 46 and 85 patients with stage I NSCLC treated with CT‐guided percutaneous MWA or thoracoscopic lobectomy, respectively, at our center from July 2013 to June 2015. Overall survival (OS), disease‐free survival (DFS), local control rate, hospital stay, and cost were evaluated. Survival curves were constructed using the Kaplan–Meier method and compared using the log‐rank test.

Results

The one and two‐year OS rates were 97.82% and 91.30% and 97.65% and 90.59% in the MWA and lobectomy groups, respectively. The one and two‐year DFS rates were 95.65% and 76.09% and 95.29% and 75.29%, respectively. No significant differences were observed in log‐rank analysis between the groups (P = 0.169). The hospital stays in the MWA and lobectomy groups were 6.62 ± 2.31 and 9.57 ± 3.19 days, respectively. The costs of MWA and lobectomy were US$3274.50 ± US$233.91 and US$4678.87 ± US$155.96, respectively. The differences were all significant (P = 0.003).

Conclusion

MWA and thoracoscopic lobectomy for stage I NSCLC demonstrate similar one and two‐year OS and DFS, with no significant differences between the two groups. MWA involved a shorter hospital stay and lower cost, thus should be considered a better option for patients with severe cardiopulmonary comorbidity and patients unwilling to undergo surgery.

Microwave ablation for lung cancer patients with a single lung: Clinical evaluation of 11 cases

Background

The study was conducted to retrospectively evaluate the safety and effectiveness of computed tomography (CT)‐guided percutaneous microwave ablation (MWA) for peripheral non‐small cell lung cancer (NSCLC) in 11 patients with a single lung after pneumonectomy.

Methods

From May 2011 to March 2015, 11 single‐lung patients (8 men and 3 women; mean age 60.3 years, range 46–71) with peripheral NSCLC underwent 12 sessions of MWA. Eleven tumors measuring 13–52 mm (mean 30.2 mm) were treated. Follow‐up was performed via CT scan at 1, 3, 6, 12, 18, and 24 months after the procedure and annually thereafter. Clinical outcomes were evaluated and complications after MWA were summarized.

Results

At a median follow‐up period of 20 months (range 6–38), four patients showed evidence of local recurrence at a rate of 36.4% (4/11). Median overall survival was 20 months. The overall survival rates at one, two, and three years after MWA were 88.7%, 63.6%, and 42.3%, respectively. Complications after MWA included pneumothorax (33.3%), hemoptysis (33.3%), intrapulmonary bleeding (25%), pleural effusion (16.7%), and pulmonary infection (8.3%). None of the patients died during the procedure or in the 30 days after MWA.

Conclusion

CT‐guided percutaneous MWA is safe and effective for the treatment of peripheral NSCLC in patients with a single lung after prior pneumonectomy.

The efficacy and safety of microwave ablation in patients with retroperitoneal metastases

BACKGROUND

Retroperitoneal metastases are common, and most present with symptoms; however, treatments for this condition are limited. This retrospective study verified the efficacy and safety of microwave ablation (MWA) in retroperitoneal metastases patients.

METHODS

Patients with pathologically confirmed malignant carcinoma and imaging showing retroperitoneal metastases were enrolled and underwent MWA. The end-points included objective response rate, time to local progression (TTLP), overall survival, visual analogue scale (VAS) score, dose of morphine pre- and post-ablation and complications.

RESULTS

Twenty-three patients were enrolled. The mean tumour diameter was 3.6 cm. Altogether, 29 tumour sites in 23 patients were ablated during 23 procedures; technical success was achieved in all 23 patients. The objective response and disease control rates were 95.7% and 100.0%, respectively. The mean TTLP and median OS were 22.8 months (95% CI: 16.1-29.6 months) and 10.6 months (95% CI: 7.4-13.8 months), respectively. In 13 patients with symptoms, the VAS values before ablation and 48 h, 1 month, 2 months, 3 months and 6 months after ablation were 5.38, 2.77 (p = 0.015), 2.15 (p = 0.001), 2.17 (p = 0.001), 1.40 (p = 0.000) and 1.71 (p = 0.006), respectively. The corresponding morphine doses were 76.9 mg, 70.7 mg (p = 0.584), 50.7 mg (p = 0.031), 55.0 mg (p = 0.097), 46.0 mg (p = 0.057) and 40.0 mg (p = 0.363), respectively. No ablation-associated mortality was observed. Major complications, minor complications and adverse events were observed in eight (34.8%), five (21.7%) and four (17.4%) patients, respectively.

CONCLUSION

MWA for the treatment of retroperitoneal metastases was effective and the complications were common.

[Long-term Efficacy of Radiofrequency Ablation Combined with Chemotherapy in the Treatment of Patients with Advanced Non-small Cell Lung Cancer --A Retrospective Study]

BACKGROUND

Radiofrequency ablation (RFA) combined with chemotherapy has a certain short-term therapeutic effect for the treatment of advanced non-small cell lung cancer (NSCLC), but whether it can improve the long-term survival rate of patients is still controversy. This study retrospectively analyzed the difference of long-term efficacy between RFA combined with chemotherapy and chemotherapy alone in the treatment of patients with advanced NSCLC.

METHODS

A total of 77 patients with stage IIIb and stage IV NSCLC who underwent radiofrequency ablation and chemotherapy in the Department of Thoracic Surgery, Xuanwu Hospital, Capital University of Medical Sciences from September 2009 to December 2015 were enrolled as the treatment group. Chemotherapy with no radiofrequency ablation was performed in 56 patients with stage IIIb and stage IV NSCLC as the control group. Two groups of patients were followed up by telephone about their living conditions. "Survival" package of R software version 3.4.1 was used for statistical analysis. Two sets of data baseline levels were tested by chi-square test. The bias was processed by Cox regression model and the survival curve was plotted using covariate mean substitution method.

RESULTS

The first-year survival rate of the treatment group was 70.74%, the two-year survival rate was 39.31% and the median survival time was 22.1 months. The one-year survival rate was 54.54% in the control group, the two-year survival rate was 19.49%, the median survival for 18.1 months. The long-term survival rate of the treatment group was better than that of the control group (P<0.05, OR=0.571).

CONCLUSIONS

Radiofrequency ablation of lung cancer combined with chemotherapy can significantly improve the 2-year survival rate of patients with stage IIIb and stage IV NSCLC.

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.

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.

Percutaneous radiofrequency ablation for medically inoperable patients with clinical stage I non-small cell lung cancer

BACKGROUND

A retrospective evaluation of percutaneous radiofrequency ablation (RFA) in medically inoperable patients with clinical stage I non-small cell lung cancer (NSCLC).

METHODS

Between 2008 and 2014, 29 medically inoperable patients with clinical stage I NSCLC underwent percutaneous RFA. We evaluated the feasibility, safety, and effectiveness.

RESULTS

There were 18 men and 11 women with a median age of 78.0 years (range 56-85), mean 76.0 years. No procedure-related deaths occurred in any of the 33 ablation procedures. The mean follow-up was 25 months. The incidence of local tumor progression was 21.0% at 25 months of median time to progression after the initial RFA. The mean overall survival (OS) was 57 months (95% confidence interval (CI) 44-70 months). The mean cancer-specific survival CSS was 63 months (95% CI 50-75 months). OS was 90.5% ± 6.4% at one year, 76.4% ± 10.7% at two, and 65.5% ± 13.6% at three years. CSS was 95.2% ± 4.6% at one, 86.6% ± 9.3% at two, and 74.2% ± 13.9% at three years in all patients. The survival for stage IA and IB cancers were 87.5% and 92.3% at one, 87.5% and 73.4% at two, and 87.5% and 58.7% at three years, respectively. Survival rates were not significantly different between the two groups (P = 0.596), with mean survival times of 65 (95% CI: 51-79 months) and 55 months (95% CI: 38-71 months), respectively.

CONCLUSION

Percutaneous RFA is a safe, feasible, and effective procedure in medically inoperable clinical stage I NSCLC patients.