DIAGNOSTIC YIELD OF THE RADIAL ENDOBRONCHIAL ULTRASOUND: HOW MUCH DOES LESION SIZE MATTER?

SESSION TITLE: Procedures SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/10/2018 01:00 PM - 02:00 PM PURPOSE: Radial endobronchial ultrasound is one of the most commonly employed guided bronchoscopic modalities for biopsying peripheral pulmonary lesions. Clinicians need to be mindful of the factors that affect the radial endobronchial ultrasound’s diagnostic yield. While we do have an appreciation that size of the lesion impacts its diagnostic yield, there is uncertainty in terms of the magnitude of this impact. To answer the question of how exactly is the diagnostic yield for a lesion affected by its size, we performed a meta-analysis. METHODS: Ovid MEDLINE, PubMed and Google Scholar databases were searched in March 2018. We included studies which had provided diagnostic yields separately for lesions less than 2 cm and more than 2 cm. Quality Assessment, Data Abstraction and Synthesis-2 (QUADAS-2) tool was used to assess the quality of eligible studies. Data was collected by two authors (MSA, JS) and differences were sorted out with consensus. Meta-analysis was performed using MedCalc (Version 18). We set I2 index value of greater than 40% as being indicative of significant heterogeneity. If significant heterogeneity was not found, fixed effects model was used. Publication bias was assessed with visual inspection of a funnel plot. RESULTS: 33 studies were included in the meta-analysis. They were published between October 2004 and January 2018. For the 1341 lesions smaller than 2 cm, the overall weighted diagnostic yield was 59.1% (95% CI 55.3 – 62.8%). On the other hand, for 2506 lesions larger than 2 cm, the overall weighted diagnostic yield was 76.6% (95% CI 73.3 – 79.7%). The Odds Ratio for successfully diagnosing a lesion larger than 2 cm was 2.5 (95% CI 2.1 – 2.9), p <0.001. The I2 index was 35.0%, reflecting no significant heterogeneity. Therefore, fixed effects model was used. CONCLUSIONS: This is the largest meta-analysis performed to date to quantitate the impact of lesion size on the diagnostic yield of radial endobronchial ultrasound. Our results show that peripheral pulmonary lesions larger than 2 cm are 2.5 times as likely to be diagnosed with radial endobronchial ultrasound, as compared to lesions smaller than 2 cm. CLINICAL IMPLICATIONS: Clinicians should strongly consider lesion size, along with the presence of a bronchus sign and distance from hilum, when assessing if a lesion is appropriate for radial endobronchial ultrasound-guided biopsy. DISCLOSURES: No relevant relationships by Muhammad Ali, source=Web Response No relevant relationships by Ann Rusk, source=Web Response No relevant relationships by Jaskaran Sethi, source=Web Response