Background: IIIa-N2 non-small cell lung cancer was significant different in survival, although N stage of lung cancer based on anatomic location of metastasis lymph node. Lymph node ratio considered of prognostic factor might be the evaluation index for IIIa-N2 non-small cell lung cancer prognosis. Therefore, the aim of the study was to evaluate the correlation between lymph node ratio and clinicopathological features and prognosis of IIIa-N2 non-small cell lung cancer prognosis.
Methods: A total of 288 cases of pathological IIIa-N2 non-small cell lung cancer were enrolled who received radical resection at the Department of Thoracic Surgery II, Peking University Cancer Hospital from January 2006 to December 2016. The univariate analysis between clinicopathological variables and lymph node ratio used Pearson's chi-squared test. Cox regression was conducted to identify the independent prognosis factors for IIIa-N2 non-small cell lung cancer.
Results: There were 139 cases in the lower lymph node ratio group, another 149 cases in the higher lymph node ratio group. Adenocarcinoma (χ²=5.924, P=0.015), highest mediastinal lymph node metastasis (χ²=46.136, P<0.001), multiple-number N2 metastasis (χ²=59.347, P<0.001), multiple-station N2 metastasis (χ²=77.387, P<0.001) and skip N2 lymph node metastasis (χ²=61.524, P<0.001) significantly impacted lymph node ratio. The total number of lymph node dissection was not correlated with the lymph node ratio (χ²=0.537, P=0.464). Cox regression analysis confirmed that adenocarcinoma (P=0.008), multiple-number N2 metastasis (P=0.025) and lymph node ratio (P=0.001) were the independent prognosis factors of disease free survival. The 5-year disease free survival was 18.1% in the higher lymph node ratio group, and 44.1% in the lower. Lymph node ratio was the independent prognosis factor of overall survival (P<0.001). The 5-year overall survival was 36.7% in the higher lymph node ratio group, and 64.1% in the lower.
Conclusions: Lymph node ratio was correlative with the pathology, highest mediastinal lymph node metastasis, multiple-number N2 metastasis, multiple-station N2 metastasis and skip N2 lymph node metastasis. Lymph node ratio was the independent prognosis factor for IIIa-N2 non-small cell lung cancer.
【中文题目：淋巴结转移率与IIIa-N2非小细胞肺癌 临床特征和生存相关性研究】 【中文摘要：背景与目的 淋巴结解剖位置是非小细胞肺癌N分期的基础，但IIIa-N2非小细胞肺癌生存差异显著，淋巴结转移率或与非小细胞肺癌预后有关，或可成为IIIa-N2非小细胞肺癌亚组评估指标。本研究探究淋巴结转移率与IIIa-N2非小细胞肺癌临床病理特征和生存的相关性。方法 纳入北京大学肿瘤医院胸外二科2006年1月-2016年12月期间直接手术的288例IIIa-N2非小细胞肺癌患者，卡方检验分析淋巴结转移率与临床病理特征相关性，Cox回归模型分析生存危险因素，Kaplan-Meier方法绘制生存曲线。结果 低淋巴结转移率139例，高淋巴结转移率149例，淋巴结转移率与腺癌（χ²=5.924, P=0.015）、最高组N2淋巴结转移（χ²=46.136, P<0.001）、多个N2淋巴结转移（χ²=59.347, P<0.001）、多站N2淋巴结转移（χ²=77.387, P<0.001）及跳跃性N2淋巴结转移（χ²=61.524, P<0.001）显著相关，与淋巴结清扫总数无关（χ²=0.537, P=0.464）。Cox回归模型多因素分析显示，腺癌（P=0.008）、多站N2淋巴结转移（P=0.025）和淋巴结转移率（P=0.001）是IIIa-N2非小细胞肺癌无病生存的独立危险因素，高淋巴结转移率组5年无病生存率为18.1%，低淋巴结转移率组5年无病生存率为44.1%。淋巴结转移率（P<0.001）是IIIa-N2非小细胞肺癌总生存的独立危险因素，高淋巴结转移率组5年总体生存率为36.7%，低淋巴结转移率组5年总体生存率为64.1%。结论 淋巴结转移率与病理类型、跳跃性N2淋巴结转移、纵隔淋巴结转移个数、纵隔淋巴结转移站数、最高组N2淋巴结转移密切相关。淋巴结转移率是IIIa-N2非小细胞肺癌生存的独立危险因素，可更有效地预测IIIa-N2非小细胞肺癌亚组间的生存差异。】 【中文关键词：肺肿瘤；IIIa-N2；淋巴结转移率；生存】.
Keywords: IIIa-N2; Lung neoplasms; Lymph node ratio; Prognosis.