Safety and Feasibility of a Novel Externally Cooled Bronchoscopic Radiofrequency Ablation Catheter for Ablation of Peripheral Lung Tumours: A First-In-Human Dose Escalation Study

Daniel P Steinfort; Phillip Antippa; Kanishka Rangamuwa; Louis B Irving; Michael Christie; Ewan Chan; Brett Marinelli; Jie Wang; Ken Y Yoneda; Shashank Raina; Felix J Herth

doi:10.1159/000529167

Safety and Feasibility of a Novel Externally Cooled Bronchoscopic Radiofrequency Ablation Catheter for Ablation of Peripheral Lung Tumours: A First-In-Human Dose Escalation Study

Respiration. 2023;102(3):211-219. doi: 10.1159/000529167. Epub 2023 Jan 31.

Authors

Daniel P Steinfort^{1

2}, Phillip Antippa^{3

4}, Kanishka Rangamuwa¹, Louis B Irving¹, Michael Christie⁵, Ewan Chan⁵, Brett Marinelli⁶, Jie Wang^{7

8}, Ken Y Yoneda⁹, Shashank Raina¹⁰, Felix J Herth¹¹

Affiliations

¹ Department of Respiratory Medicine, The Royal Melbourne Hospital, Melbourne, Victoria, Australia.
² Department of Medicine, The University of Melbourne, Melbourne, Victoria, Australia.
³ Cardiothoracic Surgery Unit, The Royal Melbourne Hospital, Melbourne, Victoria, Australia.
⁴ Department of Surgery (RMH), The University of Melbourne, Melbourne, Victoria, Australia.
⁵ Department of Anatomical Pathology, The Royal Melbourne Hospital, Melbourne, Victoria, Australia.
⁶ Division of Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
⁷ Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York, USA.
⁸ Academy of Clinical and Translational Research Jiangsu Province, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
⁹ Division of Pulmonary, Critical Care and Sleep Medicine, University of California Davis, Sacramento, California, USA.
¹⁰ Coridea LLC, New York, New York, USA.
¹¹ Department of Pneumology and Critical Care Medicine, Thoraxklinik and Translational Lung Research Center Heidelberg (TLRCH), University of Heidelberg, Heidelberg, Germany.

Abstract

Background: Radiofrequency ablation (RFA) is an established modality for percutaneous ablation of non-small cell lung cancer (NSCLC) in medically inoperable patients but is underutilized clinically due to side effects. We have developed a novel, completely endobronchial RFA catheter with an externally cooled electrode.

Objectives: The objective of this study was to establish the safety and feasibility of bronchoscopic RFA using a novel, externally cooled catheter for ablation of peripheral NSCLC.

Methods: Patients with stage I biopsy-confirmed NSCLC underwent bronchoscopic RFA of tumour 7 days prior to lobectomy. The RFA catheter was delivered bronchoscopically to peripheral NSCLC lesions, guided by radial endobronchial ultrasound, with positioning confirmed using intra-procedural cone beam CT. Pre-operative CT chest and histologic examination of resected specimens were used to establish distribution/uniformity of ablation and efficacy of tumour ablation.

Results: RFA in the first patient was complicated by dispersal of heated saline due to cough, resulting in ICU admission. The patient recovered fully and underwent uncomplicated lobectomy. Subsequently, the protocol was altered to mandate neuromuscular blockade with a pre-determined dose escalation, with algorithm-restricted energy (kJ) and irrigated saline volume (mL) constraints. A further 10 patients consented and seven underwent successful bronchoscopic RFA of peripheral NSCLC. No significant adverse events were noted. Ablation zone included tumour in all cases (proportion of tumour ablated ranged 8-72%), with uniform necrosis of tissue within ablation zones observed at higher energy levels. Ablation zone diameter correlated with RFA energy delivered (R2 = 0.553), with maximum long axis diameter of ablation zone 3.1 cm (22.9 kJ).

Conclusion: Bronchoscopic RFA using an externally cooled catheter is feasible, appears safe, and achieves uniform ablation within the treatment zone. Uncontrolled escape of heated saline poses a major safety risk but can be prevented procedurally through neuromuscular blockade and by limiting irrigation.

Keywords: Ablation techniques; Bronchoscopy; Catheter ablation; Lung cancer; Minimally invasive.

The Author(s). Published by S. Karger AG, Basel.

Publication types

Clinical Trial, Phase I

MeSH terms

Carcinoma, Non-Small-Cell Lung* / pathology
Carcinoma, Non-Small-Cell Lung* / surgery
Catheter Ablation* / adverse effects
Catheters
Feasibility Studies
Humans
Lung Neoplasms* / pathology
Lung Neoplasms* / surgery

Grants and funding

The study was sponsored by Zidan Medical.