P2.17-09 Preoperative Risk Factors of Potential Failure for Lobe-Specific Nodal Dissection in Clinical Early Stage (I-IIA) Non-Small Cell Lung Cancer

Abstract

Clinical early stage (I-IIA) non-small cell lung cancer (NSCLC) is treated with pulmonary resection and systematic nodal dissection (SND) or lobe-specific nodal dissection. The aim of this study was to identify the preoperative risk factors for potential failure of lobe-specific nodal dissection in clinical early stage NSCLC. A retrospective review was carried out on patients who underwent pulmonary lobectomy and SND for clinical early stage (I-IIA) NSCLC. Patients with computed tomography and positron emission tomography were included, whereas patients with invasive mediastinal staging and right middle lobe tumor were excluded. Lobe-specific nodal dissection failure was defined as unexpected metastasis at inferior mediastinal nodes (stations 7, 8, and 9) for both upper lobe tumors and at superior mediastinal nodes (stations 2R and 4R for right upper lobe tumors and stations 4L, 5 and 6 for left upper lobe tumors) for both lower lobe tumors. The incidence of pN2 disease following the tumor location and the factors for the failure of lobe-specific nodal dissection were analyzed. From July 2005 to May 2017, 2130 patients were included in this study. Overall, 12.5% (266/2130) of the patients had pN2 disease. Among them, 33.2% (78/266) of pN2 patients showed potential failure of lobe-specific nodal dissection. Lobe-specific nodal dissection failure was shown in 49 of 764 (6.4%), 21 of 468 (4.5%), 2 of 534 (0.4%), and 6 of 364 (1.6%) cases in right upper lobe, right lower lobe, left upper lobe and left lower lobe, respectively. At multivariable analysis, female (OR: 1.86; 95% CI 1.14-3.03; p = 0.012), right upper lobe tumor (OR: 20.98; 95% CI 5.05-87.08; p <0.001), right lower lobe tumor (OR:14.81; CI 3.43-63.97; p <0.001), higher SUVmax (≥4.75) (OR: 5.51; 95% CI 3.18-9.55; p <0.001), and adenocarcinoma histology (OR: 8.89; 95% CI 2.11-37.42; p = 0.003) were significant risk factors for the failure of lobe-specific nodal dissection Lobe specific nodal dissection revealed a considerable failure rate in clinical early stage NSCLC. Lobe-specific SND should be performed cautiously in clinical early stage NSCLC, especially in patients with female sex, right sided tumor, higher SUVmax (≥4.75) and adenocarcinoma histology.