The validity of preoperative lymph node staging guidelines of European Society of Thoracic Surgeons in non-small-cell lung cancer patients☆

OBJECTIVE: The European Society of Thoracic Surgeons (ESTS) has proposed preoperative lymph-node staging guidelines (LNSGs) for non-small-cell lung cancer (NSCLC) based on the introduction of new staging modalities into clinical practice. The validity of these guidelines was assessed. METHODS: Among the patients (n=185) with histologically confirmed NSCLC diagnosed between 2007 and 2009, who were suitable for thoracotomy, the 168 who underwent computed tomography (CT) of the chest and CT-integrated positron emission tomography (PET-CT) were included in the study. The preoperative mediastinal stage was confirmed by mediastinoscopy in all patients. A thoracotomy was done for mediastinoscopy-negative patients. The mediastinal staging results were adapted to the ESTS-LNSG (direct thoracotomy for T1-2 N0 tumour according to CT and PET-CT and invasive staging for others) and the validity of the guidelines was tested. RESULTS: In this series, the overall mediastinal lymph-node metastasis (MLNM) prevalence was 29.2%. If the guidelines had been applied, thoracotomy without invasive mediastinal staging would have been done in only 11 (6.5%) patients, and no MLNM would have been detected. Mediastinoscopy would have been performed in 157 patients and MLNM would have been found in 41 (26%). In the 116 mediastinoscopy-negative patients, MLNM would have been detected after thoracotomy in an additional eight patients. Thus, the sensitivity, specificity, and positive and negative predictive values of the guidelines were calculated as 84%, 100%, 100% and 94%, respectively. CONCLUSIONS: The preoperative LNSGs for NSCLC proposed by the ESTS are effective.