A comparison of the combined ultrasound of the mediastinum by use of a single ultrasound bronchoscope versus ultrasound bronchoscope plus ultrasound gastroscope in lung cancer staging: a prospective trial

OBJECTIVES The aim of the study was to compare diagnostic utility of combined (i.e. transbronchial and transoesophageal) ultrasound imaging with needle biopsy of the mediastinum in lung cancer (LC) staging, (a) by use of a single ultrasound bronchoscope (CUSb) and (b) by using two scopes (CUS). METHODS In consecutive LC patients, clinical stage IA-IIIB the CUS or CUSb was performed under mild sedation and, if negative, underwent lung resection with confirmatory systematic lymph node dissection. RESULTS From 214 LC patients, 110 underwent CUS and 104 underwent CUSb (618 biopsies); both revealed metastases in 50% of cases. There was 'minimal N2' in 11 of 14 false negative patients. Diagnostic sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of CUS was 91.7%, 98%, 94.6%, 98.2% and 90.7% respectively and of CUSb was 85%, 93.2%, 88.5%, 94.4%, 82%, respectively with no significant difference in yield of CUS vs CUSb (P = 0.255 and P = 0.192). The mean time of CUS (25 ± 4.4 min) was significantly longer as compared to CUSb (14.9 ± 2.3 min) (P < 0.001). No severe complications of either method were observed. CONCLUSIONS The combined ultrasound imaging of the mediastinum by use of CUSb is significantly less time-consuming and equally as effective and safe as the use of CUS for LC staging.