P2.16-42 Standard Mediastinoscopy Versus Video-Assisted Mediastinoscopic Lymphadectomy in Clinical N1 Non-Small Cell Lung Cancer

Abstract

A considerable number of patients with clinical N1 (cN1) non-small cell lung cancer (NSCLC) based on positron emission tomography–computed tomography (PET-CT) imaging have occult mediastinal nodal involvement (N2 disease). We aimed to compare the role of video-assisted mediastinoscopy lymphadenectomy(VAMLA) and standard mediastinoscopy in pre-resectional mediastinal staging in patients with cN1 disease. A total of 821 patients with potentially resectable NSCLC seen between January 2004 and November 2016 were included in the study. The preoperative mediastinal staging was accomplished by standard cervical mediastinoscopy or VAMLA in all patients except those with peripheral cT1N0 tumors. Resection via thoracotomy or video-assisted thoracoscopic surgery was performed in patients with no mediastinal lymph node metastasis. A systematic lymph node sampling or systematic lymph node dissection was performed during resectional surgery. Surgical-pathological results were compared with the pathological findings. Primary aim was to compare the sensitivities and accuracies to detect N2 by two methods. Out of 85 patients with cN1 on PET-CT, a mediastinal metastasis was disclosed in 29 patients (34.1%). Of 56 patients who underwent VAMLA 24(42.9%) were found to have N2/3 disease, whereas standard mediastinoscopy revealed N2/N3 disease in 7 patients(24.1%)(p=0.029) VAMLA and standard mediastinoscopy had both sensitivities of 85.7% to detect N2 disease(p=1). The NPVs were 87.5% and 85.7% by VAMLA and standard mediastinoscopy respectively(p=0.821). VAMLA is more accurate to detect mediastinal nodal disease in operable cN1 lung cancer, and could be used in patients with cN1 NSCLC patients since it discloses N2 disease in an important fraction of patients.