Correlation of Extracapsular Involvement of Lymph Node Metastasis With Prognosis and SOX9 Expression in Gastric Cancer Patients / 胃肠病学

ABSTRACT

Background: The extracapsular involvement (ECI) of lymph node metastasis has been considered as an important prognostic factor in patients with malignancies. Aims: To investigate the influence of ECI of lymph node metastasis on prognosis of patients with gastric cancer and its correlation with expression of transcriptional factor SOX9. Methods: A retrospective study was conducted in 200 consecutive gastric cancer patients with lymph node metastasis (TNM stage Ⅰ-Ⅲ) from Jan. 2010 to Dec. 2014 at Xi'an No. 1 Hospital. Patients were allocated into two groups according to the presence or absence of ECI, and their differences in clinicopathological characteristics, overall survival and SOX9 expression were compared. Univariate and multivariate analyses were performed by Cox proportional hazard model to identify the risk factors for poor prognosis. Results: ECI was associated with advanced T stage (T3, T4), N stage (N2, N3) and TNM stage (stage Ⅱ-Ⅲ), respectively (P<0.05). Furthermore, high expression of SOX9 was more frequently seen in metastatic lymph node with ECI than that without (94.5% vs. 58.3%, P<0.05). Kaplan-Meier survival analysis confirmed that patients in ECI group were associated with significantly shorter overall survival time (P<0.05). In multivariate analysis, TNM stage Ⅱ-Ⅲ (HR=3.224, 95% CI 2.769-5.283, P<0.001), ECI of lymph node metastasis (HR=2.388, 95% CI 1.802-3.209, P<0.001) and high expression of SOX9 in metastatic lymph node (HR=1.321, 95% CI 1.201-1.684, P=0.001) were found to be the independent risk factors of poor overall survival in patients with gastric cancer. Conclusions: ECI of lymph node metastasis is associated with high expression of SOX9 in gastric cancer patients and can be used as an independent risk factor for poor prognosis. Also, ECI is a histomorphological indicator for invasive and metastatic phenotype of gastric cancer.