Abstract

Introduction: Thermal ablation is a minimally invasive option for treating lung malignancies in patients not eligible for or refusing surgery and stereotactic body radiation therapy (SBRT).

Objective: To characterize the safety and performance of bronchoscopic microwave ablation in the lung.

Methods: This prospective, single-arm, two-center study (NAVABLATE, NCT03569111) evaluated bronchoscopic microwave ablation [Emprint™ ablation catheter kit with Thermosphere™ technology, superDimension™ navigation system v7.1]. Key inclusion criteria: (1) confirmed malignant lung nodule =30mm; (2) not abutting pleura or fissure (=5mm) or critical structures; (3) patient refusing or not a candidate for surgery and SBRT. The ablation catheter position was verified with cone-beam computed tomography.

Results: Thirty subjects (30 nodules, 66.7% primary lung, 33.3% oligometastatic) were enrolled between February 2019 and September 2020. The tumors were in the periphery (63.3%) and mid-zone (36.7%). The preprocedure median nodule size was 12.5mm (range 5-27mm). Procedure-day technical success¹ was 100%, with a mean ablative margin of 9.9±2.7mm. One-month technique efficacy¹ was 100% (30/30). There was no observed progression in any ablated nodule. One adverse event possibly related to the ablation device occurred through 30 days (primary endpoint, 3.3%, mild hemoptysis). There were no deaths or pneumothoraces. 

Conclusions: Bronchoscopic microwave ablation is an option for malignant lung nodules =30mm in patients refusing or not candidates for surgery and SBRT, with low complication rates and high technique efficacy.

1. Ahmed M. et al. J Vasc Interv Radiol 2014;25:1691