Diagnostic yield of Cone beam CT Navigation Bronchoscopy for Metastatic Lesions: A propensity matched case-control study

<bold>Background:</bold> Cone beam CT based Navigation Bronchoscopy (CBCT-NB) has been predominantly studied as diagnostic tool in primary lung cancers. Metastatic lesions are considered more challenging to diagnose, but no study has been conducted on the yield of navigation bronchoscopy in patients with pulmonary metastatic lesions (ML) compared to primary lung cancers (PL) when corrected for known lesion characteristics that affect diagnostic yield. <bold>Materials and Methods:</bold> This is a single-center, retrospective, propensity score matched case-control study. A subset of CBCT-NB patients with a proven final diagnosis of pulmonary metastases of solid tumors were propensity score matched against confirmed primary lung cancer lesions diagnosed with CBCT-NB in the period of December 2017-2021. The lesions were matched based upon the nodule characteristics: location (upper lobe, lower lobe), size, bronchus sign, and lesion solidity. <bold>Results:</bold> We identified 56 ML (mean size 14.7 mm) which identified and individually case-matched to a selection of 297 available PL. Case-matching led to finding non-significant differences in navigation success rate (PL: 89%, ML: 82.1%, 95%CI on differences: -7.5% to +21.8%) and yield (PL: 61% vs. ML: 55.4%, 95%CI on differences: -14.7 to +25.4%). The overall complication rate was comparable (4.3% and 5.4%). <bold>Conclusion:</bold> After individually matching the two cohorts of lesions based on CT assessable lesions characteristics, no significantly different navigation success or yield was detected. CT characteristics of the lesion determine procedural difficulty rather than the origin of the lesion.