Radial Endobronchial Ultrasound does not improve the Diagnostic Yield of Electromagnetic Navigation Bronchoscopy- a Randomized Controlled Trial.

<bold>Background:</bold> Bronchoscopic biopsies is a valuable tool for diagnosing small peripheral lung lesions suspected of cancer. Electromagnetic Navigation Bronchoscopy (ENB) has been developed to guide the bronchoscopist to the lesion and Radial Endobronchial Ultrasound (rEBUS) to confirm the presence of the lesion once reached. The combination of modalities might improve the diagnostic yield, however only a few studies with diverting results have been published. Primary aim: To conduct a randomized controlled trial to investigate whether ENB + rEBUS is superior to ENB alone with regards to diagnostic yield <bold>Methods:</bold> The study was conducted as a pragmatic randomized controlled trial according to CONSORT guidelines. All patients were randomized for either ENB or ENB + rEBUS. Reference test was a final histopathologic diagnosis or determined by 6 months of CT surveillance. Analyses were performed using intention to treat, with only procedures with a definitive diagnosis categorized as “diagnostic”. <bold>Results:</bold> Of 200 patients included from four centers, 185 were randomized and included in the final analyses. One hundred and thirty patients were diagnosed with malignancy of which 112 had lung cancer. There was no difference in diagnostic yield between the two groups, (ENB 43% CI95% 33-54%, ENB + rEBUS 45% CI95% 35-56%), nor did we find any difference in malignant yield or adverse events. <bold>Conclusion:</bold> ENB + rEBUS is not superior to ENB alone. The procedure is safe and well tolerated, however the diagnostic yield is lower than previously reported.