S156 ENDOBRONCHIAL ULTRASOUND: TRANSOESOPHAGEAL ULTRASOUND-GUIDED LYMPH NODE SAMPLING USING A LINEAR ULTRASONIC BRONCHOSCOPE IN THE STAGING OF LUNG CANCER

KM Skwarski, PS Hodkinson, H Huang, D Gilbert, JB McCafferty. Department of Respiratory Medicine, Royal Infirmary Edinburgh, Edinburgh, UK

Lung cancer treatment planning requires accurate staging of mediastinal lymph nodes. Current methods include mediastinoscopy, positron-emission tomography (PET-CT) and endobronchial (EBUS) or transoesophageal (EUS) ultrasound-guided lymph node aspiration. PET-CT is non-invasive but has only a moderate positive-predictive value in the assessment of lymph node metastases. The “gold standard” is mediastinoscopy, which allows surgical evaluation of lymph node stations 2, 3, 4 and 7. EBUS and EUS are less invasive than mediastinoscopy and are performed as outpatient procedures under conscious sedation. EBUS allows sampling from stations 2, 3, 4, 7, 10 and 11. EUS allows staging of stations L4, 7 and 8. We have performed over 500 EBUS procedures (2005–8) using an Olympus linear ultrasonic bronchoscope (BF-UM40). Lymph node samples were obtained using a 22G needle and tissue processed as a cell block before immunohistochemical analysis. Although EBUS is well tolerated, we have found that in a proportion of cases it was easier to aspirate lymph node stations L4, 7 and 8 via the transoesophageal route using the EBUS bronchoscope (EUS (EBUS)) and identical sample collection technique. We have analysed data from the first 40 EUS (EBUS) cases. This approach was employed to evaluate station L4 (different angle to transbronchial approach) in 15 cases, to provide additional sample from L7 in 11 cases, to access L8 in one case and to access a lung mass in four cases. Technical difficulties with the EBUS approach (extrinsic compression of the airway and inability to penetrate tracheal wall) prompted EUS (EBUS) in five cases. In addition, the EUS (EBUS) approach was used to minimise patient distress (cough, SpO₂ <90%, FEV₁ <1.0 l) in five cases. Tissue samples from lymph nodes or lung mass …