Department of Internal Medicine, Inha University College of Medicine, Incheon, South Korea.
Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, South Korea.
Thorac Cancer. 2021 Jul;12(14):2078-2084. doi: 10.1111/1759-7714.14014. Epub 2021 May 25.
Abdominal lymph node metastasis (ALNM) is common in patients with metastatic non-small-cell lung cancer (NSCLC). However, its mechanism of spread remains to be elucidated. We investigated whether thoracic duct has the role as a pathway for ALNM in NSCLC using clinical data.
We classified ALNM into subgroups by their location and evaluated its prevalence and association with clinical characteristics in 892 patients with metastatic NSCLC. The abdominal lymph nodes were classified into direct or indirect groups depending on whether they drain directly into the trunk (intestinal trunk or lumbar trunks) connected to the cisterna chyli.
One hundred-five patients (11.8%) had ALNM. The paraaortic lymph node was most commonly involved, followed by the aortocaval, left gastric, paracaval, and celiac lymph nodes. After grouping the patients by location of ALNM, 56 patients (53.3%) with ALNM were in the "direct only" group, only seven patients (6.7%) were in the "indirect only" group, and 42 patients (40.0%) were in "both" groups. In patients whose intrathoracic lesions were limited to the right thorax, there was a significantly lower prevalence of ALNM (3.4% vs. 14.3%, p < 0.001). On multivariate logistic regression analysis of clinical variables, higher N category was associated with increased risk of ALNM.
This study suggests that the thoracic duct is one of the potential routes of lymphatic spread to the abdominal lymph nodes. Clinicians should assess for the presence of ALNM during staging work-up and follow-up for NSCLC patients with intrathoracic lesion in left thorax and with high N category.
腹部淋巴结转移（ALNM）在转移性非小细胞肺癌（NSCLC）患者中很常见。然而，其播散机制仍有待阐明。我们通过临床数据研究了胸导管是否在 NSCLC 中具有作为 ALNM 途径的作用。
我们根据位置将 ALNM 分为亚组，并在 892 例转移性 NSCLC 患者中评估其患病率及其与临床特征的关系。根据腹部淋巴结是否直接排入与 cisterna chyli 相连的肠干或腰干，将其分为直接组或间接组。
105 例（11.8%）患者发生 ALNM。最常累及的是腹主动脉旁淋巴结，其次是腹主动脉腔静脉、胃左、腔静脉旁和腹腔淋巴结。根据 ALNM 位置对患者进行分组后，56 例（53.3%）ALNM 患者在“仅直接”组，仅 7 例（6.7%）患者在“仅间接”组，42 例（40.0%）患者在“两者均有”组。在胸腔内病变仅限于右胸的患者中，ALNM 的患病率显著降低（3.4% vs. 14.3%，p<0.001）。对临床变量进行多变量逻辑回归分析，较高的 N 分期与 ALNM 风险增加相关。
本研究表明，胸导管是淋巴向腹部淋巴结播散的潜在途径之一。临床医生应在 NSCLC 患者的分期检查和随访中评估是否存在 ALNM，这些患者的胸腔内病变位于左侧且 N 分期较高。
