CT Bronchus Sign Improves Chance of Peripheral Pulmonary Lesion Diagnosis

When using guided bronchoscopy, peripheral pulmonary lesions were >3 times more likely to be diagnosed with computed tomography (CT) bronchus sign than peripheral pulmonary lesions without CT bronchus sign, according to a systematic review and meta-analysis published in Annals of the American Thoracic Society.

Data for analysis were found by searching Embase, Google Scholar, MEDLINE, and Scopus databases for studies that examined the association between CT bronchus sign and diagnostic yield for peripheral pulmonary lesions when using guided bronchoscopy. The initial search yielded 3391 titles. After screening for duplicates and studies that did not have sufficient diagnostic information or did not have adequate follow-up to confirm the diagnosis, the final meta-analysis included 23 studies.

Of the 2199 participants with positive CT bronchus sign, the diagnostic yield was 74.1% (95% CI, 68.3%-79.5%). Of the 971 participants without CT bronchus sign, the diagnostic yield was 49.6% (95% CI, 39.6%-59.5%). The odds ratio for diagnosing a peripheral pulmonary lesion with a CT bronchus sign vs without CT bronchus sign was 3.4 (95% CI, 2.4-5.0).

The investigators concluded, “To date this is the largest analysis assessing the utility of CT [bronchus sign] for predicting diagnostic yield of guided bronchoscopies for [peripheral pulmonary lesions]. CT [bronchus sign] appears to be associated with a higher diagnostic yield. Importantly, the overall weighted diagnostic yield for [peripheral pulmonary lesions] without CT [bronchus sign] is only 50%. CT [bronchus sign] along with the size of the [peripheral pulmonary lesion] and the distance from the hilum should be strongly considered when determining whether a [peripheral pulmonary lesion] is amenable to guided transbronchial biopsy.”

The researchers added that new guided bronchoscopic modalities less dependent on the presence of CT bronchus sign could be available in the future.

Reference

Ali MS, Sethi J, Taneja A, Musani A, Maldonado F. CT bronchus sign and the diagnostic yield of guided bronchoscopy for peripheral pulmonary lesions: a systematic review and meta-analysis [published online June 7, 2018]. Ann Am Thorac Soc. doi:10.1513/AnnalsATS.201711-856OC