Complete and systematic mediastinal nodal staging for lung cancer (SCORE study)>

Background: Guidelines recommend endosonography for mediastinal nodal staging of lung cancer but do not specify how: through endobronchial (EBUS), esophageal (EUS-(B) or both? Additionally, there is no consensus whether endosonography should be performed systematically or target abnormal CT-PET findings only.Hypothesis: Complete (combined endobronchial and esophageal) and systematic (assessment of all hilar and mediastinal nodal regions including routine sampling of station 4R, 7, 4L) endosonographic staging using a single EBUS scope improves loco-regional staging (N2, N3) versus targeted (PET-CT directed) EBUS staging alone.Methods: Prospective, multicentre international study in patients with resectable (suspected) NSCLC. Prior to endoscopy, target nodal station (s) were defined based on imaging (PET-CT). Patients underwent a systematic EBUS followed by a systematic EUS-B procedure using the EBUS scope. Node(s) suspicious on CT/PET and/or EBUS/EUS-B imaging were sampled as well as stations 4R, 4L and 7 (in case short axis > 8 mm). Surgical pathological staging was the reference standard.Results: 229 patients underwent EBUS and EUS-B. The prevalence of mediastinal N2/3 disease was 45% (103/229). A (PET-) CT guided targeted nodal approach by EBUS identified 81 patients with N2-3 disease (sensitivity 79%, NPV 85%). 4 additional patients with N2/3 disease were found by systematic EBUS (sensitivity 83%, NPV 88%) and 5 more by EUS-B (90 patients total – sensitivity 87%, NPV 91%).Conclusion: Complete (EBUS and EUS-B) and systematic endosonographic mediastinal staging is superior to a targeted EBUS ‘hit and run’ strategy based on CT (PET) findings.