Factors Associated with Nodal Upstaging in Clinical T1a-bN0M0 Non-Small Cell Lung Cancers

Nodal upstaging of lung adenocarcinoma occurs when unexpected pathological lymph node metastasis is found after surgical intervention, and may be associated with a worse prognosis. In this study, we aimed to determine the predictive factors of nodal upstaging in cT1a-bN0M0 primary lung adenocarcinoma. We retrospectively reviewed a prospective database (January 2011 to May 2017) at National Taiwan University Hospital and identified patients with cT1a-bN0M0 (solid part tumor diameter ≤ 2 cm) lung adenocarcinoma who underwent video-assisted thoracoscopic lobectomy. Logistic regression models and survival analysis were used to examine and compare the predictive factors of nodal upstaging. A total of 352 patients were included. Among them, 28 (7.8%) patients had nodal upstaging. Abnormal preoperative serum carcinoembryonic antigen (CEA) levels, solid part tumor diameter ≥ 1.3 cm, and consolidation-tumor (C/T) ratio ≥ 0.50 on chest computed tomography (CT) were significant predictive factors associated with nodal upstaging, and patients with nodal upstaging tended to have worse survival. Standard lobectomy is recommended for patients with these predictive factors. If neither of the predictive factors are positive, a less invasive procedure may be a reasonable alternative. Further studies are needed to verify these data.