ObjectiveTo explore the clinical utility and safety of electromagnetic navigation bronchoscopy (ENB)-guided microwave ablation (MWA) in the patients with inoperable high-risk pulmonary nodules.MethodsClinical data of patients who were diagnosed with inoperable pulmonary nodules highly suspected as malignant tumors and treated with ENB-guided MWA in Zhongshan Hospital, Fudan University from December 2019 to September 2020 were retrospectively collected and analyzed to evaluate the efficacy and safety of the procedure. There were 6 males and 3 females aged 72.0 (59.5-77.0) years.ResultsTotally ENB-guided MWA was performed in 9 patients with 12 lesions. All patients suffered from at least one chronic comorbidity. The inoperable reasons included poor pulmonary function (55.6%), comorbidities of other organs which made the surgery intolerable (33.3%), multiple lesions in different lobes or segments (22.2%), personal wills (22.2%) and advanced in age (11.1%). The median diameter of nodules was 13.5 (9.5-22.0) mm and the median distance from the edge of nodules to pleura was 5.3 (1.8-16.3) mm. Bronchoscope maneuver to the targeted lesions was manipulated according to navigation pathway under visual and X-ray guidance and confirmed with radial ultrasound probe. Rapid on-site evaluation also helped with primary pathological confirmation of biopsy specimen. Among all the lesions, 4 adenocarcinoma, 1 non-small cell lung cancer-not otherwise specified and 2 inflammatory lesions were reported in postoperative pathological diagnosis, while no malignant cells were found in 5 specimens. The ablation success rate was 83.3% (10/12). For the two off-targeted lesions, percutaneous ablations were performed as salvage treatment subsequently. The median hospitalization time was 3.0 (2.0-3.0) days and no short-term complications were reported in these patients.ConclusionENB-guided MWA is a safe and effective procedure for patients with high-risk pulmonary nodules when thoracic surgery cannot be tolerated.