Abstract:Objective: At present, there are few studies on the metastasis model of mediastinal lymph node (MLN) in stage I non-small-cell lung cancer (NSCLC). This study aimed to identify if patients with different clinical characteristics have different changes in metastatic rates between lobe-specific and non-specific MLN stations in patients with preoperative stage I NSCLC, so as to predict clinical indications of lobe-specific MLN dissection in patients with preoperative stage I NSCLC. Methods: We examined 609 patients with clinical stage I NSCLC for lobectomy with complete MLN dissection. We analyzed the metastatic rates of lobe-specific and other MLN stations with patient characteristics, including T stage, tumor histology, gender and age. Results: It was revealed that metastasis was limited to lobe-specific MLNs for stage Ⅰ patients meeting the following criteria: ①male, > 60 years, squamous cell tumor, and tumor≤5cm. ②male, ≤60 years, squamous cell tumor, and tumor≤ 3 cm. ③female, squamous cell tumor, and tumor≤3 cm. ④adenocarcinoma and tumor≤2 cm. Conclusion: Lobe-specific mediastinal lymph node MLN dissection is suitable for the patients with characteristics mentioned above. For other patients, there was a considerable increasing risk of metastasis, and complete MLN dissection remains the most effective method.