Microwave Ablation of Lung Tumors Near the Heart: A Retrospective Review of Short-Term Procedural Safety in Ten Patients

Safety and Effectiveness of Percutaneous Image-Guided Thermal Ablation of Juxtacardiac Lung Tumors

PURPOSE

To evaluate the safety and effectiveness of percutaneous image-guided thermal ablation (IGTA) for juxtacardiac lung tumors.

MATERIALS AND METHODS

This bi-institutional retrospective cohort study included 23 consecutive patients (13 [57%] male; mean age, 55 years ± 18) with 30 juxtacardiac lung tumors located ≤10 mm from the pericardium treated in 28 IGTA sessions (25 sessions of cryoablation and 3 sessions of microwave ablation) between April 2008 and August 2022. The primary outcome was any adverse cardiac event within 90 days after ablation. Secondary outcomes included noncardiac adverse events, local tumor progression-free survival (LT-PFS), and the cumulative incidence of local tumor progression with death as a competing risk. Two tumors treated without curative intent or follow-up imaging were considered in the safety analysis but not in the progression analysis.

RESULTS

The median imaging follow-up duration was 22 months (interquartile range [IQR], 10-53 months). Primary technical success was achieved in 25 (89%) ablations. No adverse cardiac events attributable to IGTA occurred. One patient experienced a phrenic nerve injury. The median LT-PFS duration was 59 months (IQR, 32-73 months). At 1, 3, and 5 years, LT-PFS was 90% (95% CI, 78%-100%), 74% (CI, 53%-100%), and 45% (CI, 20%-97%), respectively, and the cumulative incidence of local tumor progression was 4.3% (CI, 0.29%-19%), 11% (CI, 1.6%-30%), and 26% (CI, 3.3%-58%), respectively.

CONCLUSIONS

IGTA is safe and effective for lung tumors located ≤10 mm from the pericardium. No adverse cardiac events were not observed within 90 days after ablation.

Microwave Ablation Versus Wedge Resection for Stage I Non-small Cell Lung Cancer Adjacent to the Pericardium: Propensity Score Analyses of Long-term Outcomes

Objective

The present study has compared the long-term outcomes between performing wedge resection (WR) and microwave ablation (MWA) as first-line treatment of stage I non–small cell lung cancer (NSCLC) patients with tumors adjacent to the pericardium.

Materials and Methods

Between January 2014 and December 2018, a total of 223 consecutive patients with T1N0 NSCLC underwent first-line treatment by WR (n = 155) or image-guided lung MWA (n = 68). This study has compared the progression-free survival (PFS) and overall survival (OS) rates between the two treatments before and after propensity score matching. Subgroup analysis of these outcomes was conducted based on the distance from the pericardium.

Results

The median follow-up time was 47 months. Propensity matching yielded 56 pairs of patients. In the two matched groups, the PFS rates in the WR group at 3 and 5 years were 66.0% and 56.0% and 54.0% and 36.0%, respectively, in the MWA group (P = 0.029). Meanwhile, the corresponding OS rates for the WR group at 3 and 5 years were 81.0% and 72.0% and 60.0% and 55.0% in the MWA group, respectively (P = 0.031). Subgroup analysis, done according to the treatment modality, indicated that local tumor recurrence and PFS for NSCLCs that were close but not contiguous to the pericardium were different from those contiguous to the pericardium (P = 0.018 and P = 0.025, respectively).

Conclusion

WR provided better long-term tumor control and OS compared to MWA for stage I NSCLC adjacent to the pericardium as a first-line treatment. MWA can be considered as an alternative option for high-risk and inoperable patients, particularly for tumors that were not contiguous to the pericardium.

Contralateral Dependent Position During Percutaneous CT-Guided Core Needle Biopsy for Small (≤ 20 mm) Lung Lesions Adjacent to the Pericardium: Effect on Procedures and Complications

PURPOSE

To assess the effect of contralateral dependent position on procedures and complications of percutaneous computed tomography (CT)-guided core needle biopsy (PCT-CNB) for small (≤ 20 mm) lung lesions adjacent to the pericardium.

MATERIALS AND METHODS

Retrospective view was performed to identify patients with small (≤ 20 mm) lung lesions located within 10 mm of the pericardium and who underwent PCT-CNB in the standard supine or prone position (n = 66) or in contralateral dependent position ( n = 35) between March 2010 and January 2020. In 35 patients, CT images in the contralateral dependent position were compared with images in the supine position to assess the mean distance of the lesion from the pericardium and the mean length of interface between these two positions. Complications including rates of pneumothorax, chest tube insertion, and pulmonary hemorrhage were assessed.

RESULTS

In comparison with axial images in supine position, the pericardium were located farther from the lesion in the contralateral dependent position; the mean distance of lesions from the pericardium became farther (P < 0.001), and the mean length of interface with the pericardium became shorter (P = 0.008). There was no difference in the complication rates between supine or prone position and contralateral dependent position (pneumothorax, P = 0.098; pulmonary hemorrhage, P = 0.791).

CONCLUSION

Placing patients in contralateral dependent position may confer some advantages, including maximizing distance and minimizing length of interface of the lesion to the pericardium during PCT-CNB for small (≤ 20 mm) lung lesions adjacent to the pericardium.

Hydrodissection of the Retro-Sternal Space to Protect the Pericardium During Sternal Cryoablation

PURPOSE

To report the retro-sternal space hydrodissection technique used to displace the heart and the pericardium posteriorly for thermoprotection ahead of sternal cryoablation (CA).

METHODS AND MATERIALS

Between May 2015 and March 2020, hydrodissection of the retro-sternal space was performed in 5 consecutive patients (5 female; mean age 55.2 ± 9.3 years, range 41-65) who underwent percutaneous image-guided cryoablation of the sternum. The number of needles required, the implemented approach, volume of injectate to achieve hydrodissection, hydrodissection procedure time, distance between the lesion and the pericardium before and after hydrodissection, distance between the ice-ball and the pericardium, technical success and complications were retrospectively assessed.

RESULTS

Technical success, defined as the completion of a full dual freeze protocol without contact between the ice-ball and the pericardium, was achieved in all cases (5/5, 100%). One to two needles were used to perform hydrodissection via a perpendicular (3/5) or an anterior oblique approach (2/5) and a mean hydrodissection procedure time of 10.4 ± 2.6 min (range 8-14). Minimum distance between the lesion and the pericardium increased from mean 5.8 ± 3.8 mm (range 0-10) before hydrodissection to a mean 22.2 ± 5.8 mm (range 18-32) after, with a mean distance between the final ice-ball and the pericardium of 11.6 ± 8.7 mm (range 7-27). A mean of 198 ± 79.8 mL (range 90-290) of iodinated contrast was injected. There were no immediate, short- or medium-term complication noted.

CONCLUSION

Hydrodissection of the retro-sternal space is a feasible technique for sternal cryoablation in order to protect the pericardium from freezing for sternal cryoablation.

Usefulness of percutaneous microwave ablation for large non-small cell lung cancer: A preliminary report

The role of microwave ablation (MWA) in patients with non-small cell lung cancer (NSCLC) remains ill-defined. This retrospective study evaluated the oncological outcomes of CT-guided MWA in patients with large NSCLC. Kaplan-Meier analysis was used to evaluate overall survival (OS) and cancer-specific survival (CSS). The log-rank test was used to compare survival between patients with an NSCLC size greater or smaller than 4 cm. The likelihood of local tumor progression (LTP) was analyzed using a multivariable regression model. A total of 53 patients with 65 tumors were analyzed. The mean tumor size was 5.0±1.8 cm. At the 1-month CT scan, complete tumor ablation was observed in 44.6% of cases. In 18.5% of cases a redo-MWA session was carried out, while in 4.6%, a third MWA was necessary to obtain complete tumor necrosis. The mean follow-up was 28.1±20.6 months with a median duration of 21.5 months. The 1-year, 2-year, 3-year and 5-year OS rates were 78.2, 48.3, 34.8 and 18.3%, respectively. The median CSS was 25 months (95% CI 15.5–34.5). The 1-year, 2-year, 3-year and 5-year CSS rates were 84.3, 53.7, 42.1 and 30.0%, respectively. OS in patients with tumor size ≥4 cm was significantly lower when compared with those having smaller tumors (P=0.03). LTP was observed in 19 patients (35.8%). Incomplete tumor ablation [odds ratio (OR) 6.57; P<0.05] and tumor size ≥4 cm (OR 0.18; P<0.05) were significant independent predictors of LTP. In conclusion, CT-guided MWA may represent a useful tool in the multimodality treatment of patients with large advanced NSCLC.

Safety and efficacy of thermal ablation for subpleural lung cancers

BACKGROUND

The study was conducted to assess the safety and efficacy of thermal ablation for the treatment of subpleural lung cancer.

METHODS

Eighty-nine patients with 101 subpleural lung cancers were identified between January 2012 and July 2018 in our database and included in this study. Tumors were classified as adhering to cervical, costal, diaphragmatic, and mediastinal pleurae. Lesions were categorized based on their relationship to the pleura: close to the pleura, causing pleural indentation, and involving the pleura. The complete ablation rate, local progression-free survival, complications, and associated factors were analyzed.

RESULTS

Subpleural lung cancers included lesions located under costal (n = 69), mediastinal (n = 17), cervical (n = 8), and diaphragmatic (n = 7) pleurae. The rate of complete ablation was 87.1% and the local progression-free survival rates at 3, 6, 12, and 24 months were 86%, 77%, 75%, and 64%, respectively. Tumor size was the most important factor influencing technique efficacy (P < 0.05), with a complete ablation rate of only 55.6% in lung cancers measuring > 30 mm. There were nine (10.11%) major complications, including one chest abscess, five cases of pneumothorax, and three cases of hemothorax. The occurrence of major complications was associated with increased levels of pain within 48 hours post-procedure (P < 0.05).

CONCLUSION

Local thermal ablation is a safe and effective treatment for subpleural lung cancers. Tumor size was the most significant factor affecting technique efficacy. Post-procedure pain indicated the possibility of major complications.