The efficacy of convex probe endobronchial ultrasound for sampling of parenchymal lung lesions

CT guided biopsy is the gold standard for assessment of pulmonary masses if transbronchial biopsy under fluoroscopy is not feasible due to parabronchial lesion location. Both of these modalities are associated with complications including bleeding and pneumothorax leading to significant morbidity. Convex probe endobronchial ultrasound (CP-EBUS) is an established technique for assessment of mediastinal lymph nodes in the staging of lung cancer. In this study we sought to examine the efficacy of CP-EBUS as a standalone technique in the assessment of central parenchymal pulmonary lesions. We reviewed 3739 bronchoscopy reports from 2009 to 2013 at our centre. Total number of EBUS procedures performed, the number of these targeting primary lesions, lesion size and location radiologically were noted. Histopathological results were reviewed to establish diagnostic yield and crossover confirmation in some cases. 41 CP-EBUS guided procedures targeting parenchymal lung masses were performed over the period. The histological diagnosis was achieved in 35 out of 41 cases. Histology results included small and non small cell subtypes as well as neuroendocrine and carcinoid tumours. EBUS FNA was also effective in immuohistochemical and genotypic analysis of diagnosed lesions. All lesions were proximal with a mean distance of 4.6cm from the carina and 75% were larger than 2 cm in size. No lobar predominance was noted. These results suggest that EBUS is effective and represents an alternative to CTBX for assessment of selected proximal pulmonary lesions.