CT-guided microwave ablation of hepatic malignancies via transpulmonary approach without ancillary techniques

Abstract

Objectives: The objectives of the study were to determine the safety and efficacy of computed tomography (CT)-guided transpulmonary percutaneous microwave ablation (MWA) for hepatic malignancies without the use of ancillary techniques. Material and Methods: A retrospective review was performed on patients who underwent MWA for hepatic malignancy between January 2014 and February 2020 at a single tertiary center. Imaging was reviewed for each procedure to identify MWA showing transpleural transgression on CT scans. For these patients, demographics, ablation data, pulmonary complication rate, and predictors of pneumothorax were analyzed. Results: A total of 71 consecutive sessions (62.1 ± 11.3 years, 79% of males) of MWA were performed to treat 71 tumors (1.90 ± 0.96 cm) via transpulmonary approach under CT guidance. Technical success was achieved in all cases immediately after the procedure. At 1-month follow-up, 65/69 (94.2%) patients had no residual disease (two patients were lost to follow-up). Pulmonary complications occurred in 26/71 (36.6%) sessions, and 15/26 (57.7%) were minor requiring no intervention. Pneumothorax occurred in 14/71 (19.7%) sessions, and the rate of major pneumothorax requiring chest tube was 8/71 (11.3%). Lesions on the left side of the liver (segments I–IV) and intraprocedural probe adjustment were found to be independent predictors of developing major pneumothorax (P = 0.007 and 0.028, respectively). There were no reported pulmonary complications at the 1-month follow-up. Conclusion: CT-guided transpulmonary MWA is safe and effective in treating hepatic malignancies. Although it is associated with the risk of developing pulmonary complications, patients underwent successful ablation of their hepatic malignancies without life-threatening complications and mortality.

Editorial comment: a review on radiofrequency, microwave and high-intensity focused ultrasound ablations for hepatocellular carcinoma with cirrhosis

“…In-vivo and ex-vivo studies show that MWA achieves larger ablation zones and faster ablation times, thus allowing tumors to be treated with fewer probe insertion points compared to RFA (14). From a practical point of view, several advantages can be reaped; shorter MWA ablation time, shorter duration of anesthesia, and a far less "liver sticks or insertions" which in our opinion inevitably decreases complications (9). The article does mention cryoablation as an option for liver ablation, and cites a few older studies from the surgical literature to discount it as safe option.…”

“…We would like to offer evidence supporting MWA being a safe and effective method of treatment even in challenging locations such as peri-cardiac or sub-diaphragmatic areas without routine use of hydrodisplacement (3)(4)(5)(6)(7). Even though continued investigation is still necessary to shed more light on the role of MWA in treating HCC in these locations, it is reassuring to see more and more studies supporting the safety and efficacy of MWA in the treatment of HCC, even in previously thought prohibitive locations and even in patients beyond early stage HCC (8)(9)(10).…”

Percutaneous microwave ablation for early-stage intrahepatic cholangiocarcinoma: A single-institutional cohort

“…As per the SIR classification system for AEs, only one major complication (therapy and <48 h hospitalization required) occurred, which was hemopneumothorax resulting from intentional transpleural probe placement. [ 18 ] This resolved with chest tube placement for <24 h without affecting the length of hospital stay. In the study of Yu et al ., [ 17 ] no major complication occurred within 30 days post ablation, and all minor complications resolved without further intervention.…”

Current perspectives on microwave ablation of liver lesions in difficult locations

“…The most severe complication was pneumothorax needing chest tube placement (11%), and there were no pulmonary complications at the 1-month follow-up. [ 13 ] According to their results, the most significant predictor of pneumothorax was lesional location within the left hemi-liver. In addition, some authors mention that subdiaphragmatic left-sided lesions should be performed with extra caution as access to these lesions can be more difficult as they oscillate more with respiratory or cardiac motion.…”