直径≤3cm的周围型非小细胞肺癌纵隔淋巴结转移规律的初步研究

Primary Study on Mediastinal Lymph Node Metastasis in Patients with ≤3 cm Peripheral Non-small Cell Lung Cancer

目的探讨直径≤3cm的周围型非小细胞肺癌(non-small cell lung cancer,NSCLC)纵隔淋巴结转移的情况,分析早期周围型NSCLC纵隔淋巴结转移的规律。方法 2000年1月1日～2008年12月31日治疗直径≤3cm的周围型NSCLC161例,男89例,女72例,年龄(63.4±10.7)岁,行肺叶切除或肺局限性切除加系统性纵隔淋巴结清扫术,分析其临床特征、病理特点及纵隔淋巴结转移规律。结果全组手术顺利,无死亡及严重并发症发生。肺叶切除153例,肺楔形切除7例,肺段切除1例。全组共清扫淋巴结2456枚,平均每例4.5±1.6组、13.1±7.3枚。术后病理:腺癌99例,鳞癌30例,肺泡细胞癌19例,其他类型肺癌13例。术后TNM分期:ⅠA期50例,ⅠB期62例,ⅡA期6例,ⅡB期10例,ⅢA期33例。N1组淋巴结转移率为23.6%(38/161),N2组转移率为20.5%(33/161),其中隆突下淋巴结转移率为8.1%(13/161),跳跃式纵隔转移率为6.8%(11/161),全组未发现下纵隔淋巴结转移。肺泡细胞癌及直径≤2cm的鳞癌、直径≤1cm的腺癌均无pN2转移。上肺癌发生pN2转移时上纵隔100%(19/19)受累,其中21.1%(4/19)同时伴有隆突下淋巴结转移;下肺癌则除主要转移至隆突下外(64.3%,9/14),还常直接单独转移至上纵隔(35.7%,5/14)。转移的纵隔淋巴结左肺癌主要分布在第5、6、7组,右肺癌主要分布在第3、4、7组。结论对于直径≤3cm的周围型NSCLC,肿瘤直径越大,其纵隔淋巴结转移率越高,肺泡细胞癌、直径≤2cm的鳞癌和≤1cm的腺癌其纵隔淋巴结转移率相对较低;上肺癌主要转移在上纵隔,下肺癌则隆突下及上纵隔均可转移;第5、6、7组淋巴结是左肺癌主要转移的位置,第3、4、7组是右肺癌主要转移的位置,术中应重点清扫。

Objective To study the pattern of mediastinal lymph node metastasis in patients with peripheral non-small cell lung cancer （NSCLC） that are ≤3 cm in diameter. Methods From January 2000 to December 2008,a total of 161 patients with NSCLC [89 men and 72 women,aged （63.4±10.7） years; ≤3 cm in diameter] underwent lobectomy or partial resection with systematic mediastinal lymphadenectomy in our hospital. The removed lymph nodes were subjected for pathological examination afterwards. The clinicopathological features and the metastasis pattern of the mediastinal lymph nodes were investigated. Results No death or serious complications occurred in our patients. Of them,153 cases underwent lobectomy,7 underwent pulmonary wedge resection and 1 received pulmonary segment resection. Totally 2456 lymph nodes were dissected,with an average of （4.5±1.6） groups and （13.1±7.3） lymph nodes in each patient. Among the 161 patients,99 patients were diagnosed with adenocarcinoma,30 were squamous carcinoma,19 were bronchioloalveolar carcinoma （BAC） and 13 were other types of lung cancer. Postoperative TNM staging：ⅠA stage was observed in 50 cases,ⅠB 62 cases,ⅡA 6 cases,ⅡB 10 cases,and ⅢA 33 cases. The lymph node metastasis rates of N1 and N2 were 23.6% （38/161） and 20.5% （33/161） respectively,subcarinal lymph node metastasis rate was 8.1% （13/161）,and skipping mediastinal lymph node metastasis rate was 6.8% （11/161）. No metastasis was found in the lower mediastinal lymph nodes. No N2 lymph node metastasis was observed in patients with BAC,≤2 cm squamous cell carcinoma or ≤1 cm adenocarcinoma. In the cases of upper lobe lung cancer,upper mediastinal lymph nodes were involved in 100% of the patients （19/19）,and 21.1% of them were accompanied by subcarinal lymph node metastasis （4/19）; while in the patients with lower lobe lung cancer,64.3% （9/14） showed subcarinal lymph node metastasis and 35.7% （5/14） had the upper mediastinal lymph nodes being involved. The metastatic mediastinal lymph nodes of left lung cancer mainly distributed at the 5th,6th,and 7th groups,while those in right lung cancer mainly at 3rd,4th,and 7th groups. Conclusions In the patients with peripheral NSCLC ≤3 cm in diameter,the larger tumor size,the higher rate of metastatic mediastinal lymph nodes. BAC,squamous cell carcinoma ≤2 cm,and adenocarcinoma ≤1 cm in diameter have a low rate of lymph node metastasis relatively. The upper lung cancer mainly involves the upper mediastinal lymph nodes; while the lower lung cancer usually involves both subcarinal and upper mediastinal lymph nodes. The 5th,6th,and 7th groups lymph nodes are the main locations of metastasis for left lung cancer,while the 3rd,4th,and 7th groups are the major locations of metastasis of left lung cancer. We should focus on these places during mediastinal lymph node dissection.