Background: More early-stage non-small cell lung cancer (NSCLC) are diagnosed in time and treated surgically, but systematic lymph node dissection can not bring enough survival benefits for them, and even increase the probability of postoperative complications. This study aims to analyze the risk factors and evaluate mediastinal lymph node metastasis sites in different lung lobes for NSCLC with diameter ≤2 cm, so as to provide reference for surgery.
Methods: We collected 1051 patients with pulmonary nodule diameter ≤2 cm who were treated by pulmonary lobectomy with lymph node sampling/dissection in Department of Thoracic Surgery of the First Affiliated Hospital with Nanjing Medical University from December 2009 to December 2019. SPSS 26.0 statistical software was used for statistical analysis, to explore the risk factors and evaluate mediastinal lymph node metastasis sites in different lung lobes.
Results: 95 of 1051 (9.04%) patients presented lymph node metastasis. Male, pathological non-adenocarcinoma, 1 cm<tumor diameter≤2 cm, spread through air spaces (STAS), visceral pleural invasion (VPI), vascular invasion, low differentiation of adenocarcinoma, and micropapillary or solid adenocarcinoma subtype were the risk factors for lymph node metastasis (P<0.01). Male, 1 cm<tumor diameter≤2 cm, STAS, VPI and vascular invasion were independent risk factors for lymph node metastasis (P<0.05). Lymph node metastasis of #2R, #4R, #9 appeared in upper and middle lobe of right lung (P<0.05), and #7 appeared in right lower lobe (P<0.05). Lymph node metastasis of #5 and #6 in the left upper lobe was more common (P<0.05), while metastasis of #7 and #9 had no significant difference (P>0.05). Lymph nodes in group N1 were significantly correlated with lymph node metastasis in groups #2R, #4R, #5, #6, #7 and #9 (P<0.01).
Conclusions: Lobe-specific lymph node dissection (LSND) can be performed for early-stage NSCLC. Male, pathological non-adenocarcinoma, 1 cm<tumor diameter≤2 cm, STAS, VPI, vascular invasion, low differentiation of adenocarcinoma, and micropapillary or solid adenocarcinoma subtype would increase the risk of lymph node metastasis.
【中文题目：直径≤2 cm非小细胞肺癌淋巴结转移因素 及采样范围评估】 【中文摘要：背景与目的 越来越多的早期肺癌被及时诊断并手术治疗，但是系统性淋巴结清扫（systematic lymph node dissection, SND）不能为其带来足够的生存获益，甚至增加术后并发症发生概率。本研究旨在分析直径≤2 cm非小细胞肺癌（non-small cell lung cancer, NSCLC）淋巴结转移的危险因素以及不同肺叶好发的纵隔淋巴结转移站点，为手术提供参考意见。方法 纳入2009年12月至2019年12月于南京医科大学第一附属医院胸外科行肺叶切除术+淋巴结采样/清扫术治疗的肺结节患者（直径≤2 cm）共1051例，运用SPSS 26.0统计软件对资料进行统计分析，探讨淋巴结转移的危险因素以及不同肺叶好发的纵隔淋巴结转移站点。结果 1051例患者中发生淋巴结转移95例，转移率为9.04%，其中男性、病理非腺癌、肿瘤直径大于1 cm但不大于2 cm、存在气道播散（spread through air spaces, STAS）、胸膜侵犯（visceral pleural invasion, VPI）、脉管浸润、腺癌低分化、腺癌亚型为微乳头或实体型是淋巴结转移的危险因素（P<0.01）；男性、肿瘤直径大于1 cm但不大于2 cm、存在STAS、VPI、脉管浸润是淋巴结转移的独立危险因素（P<0.05）；右肺上、中叶易出现#2R、#4R、#9淋巴结转移（P<0.05），右肺下叶易出现#7淋巴结转移（P<0.05）；左肺上叶易出现#5、#6淋巴结转移（P<0.05），#7、#9转移无统计学差异（P>0.05）；N1组淋巴结与#2R、#4R、#5、#6、#7、#9组淋巴结转移有明显相关性（P<0.01）。结论 对于早期NSCLC，可以进行肺叶特异性淋巴结清扫（lobe-specific lymph node dissection, LSND），当患者为男性、病理为非腺癌、肿瘤直径大于1 cm但不大于2 cm、存在STAS、VPI、脉管浸润、腺癌低分化、腺癌亚型为微乳头或实体型时，其淋巴结转移的风险增高。 】 【中文关键词：肺肿瘤；淋巴结转移；危险因素；肺叶特异性淋巴结清扫】.
Keywords: Lobe-specific lymph node sampling; Lung neoplasms; Lymph node metastasis; Risk factors.