Endobronchial ultrasound trans-bronchial needle aspiration (EBUS-TBNA) in Malta – improving diagnostic yield in a low volume centre

Abstract

EBUS-TBNA at Mater Dei Hospital (MDH), which serves a population of about 432000, was audited over a 2 year period. Our aim was to assess results obtained and factors associated with improved diagnostic yield. All patients who underwent EBUS-TBNA at MDH were included and data was collected retrospectively. 71 EBUS TBNA procedures were performed on 70 patients. Sensitivity for malignancy was 93% (40/43) and sensitivity for granulomatous disease was 72% (16/22). The overall diagnostic sensitivity was 84.5% (60/71). Sampling multiple stations as opposed to a single station was associated with a better histology diagnostic yield (90.3% vs 60% p=0.004) as well as a better yield on cytology (83.9% vs 50% p=0.003). It also led to an improved overall combined diagnostic yield (93.5% vs 77.5%) although this narrowly missed statistical significance (p=0.06). Targeting multiple stations also correlated with obtaining an adequate histology sample (96.8% vs 82.5% p=0.05). This effect was even more pronounced for granulomatous disease with improved diagnostic histology yield (100% vs 43.8% p=0.005) diagnostic cytology yield (89% vs 25% p=0.002) and overall combined diagnostic yield (100% vs 62.5% p=0.035) Increasing lesion size was predictive of obtaining an adequate tissue sample (p=0.03) histology diagnostic yield (p=0.05) and overall diagnostic yield (p=0.04) but there was no correlation between lesion size and yield on cytology (p=0.389). Sampling multiple stations and targeting larger lesions led to an improved diagnostic yield; the effect of targeting multiple stations was even more pronounced in granulomatous disease.