Predictive Factors for Lymph Node Metastasis in Submucosal Gastric Cancer

Purpose: Lymph node metastasis is an important prognostic factor in patients with early gastric cancer. Therefore, we analyzed the predictive factors for lymph node metastasis in submucosal gastric cancer and explored the feasibility of minimally invasive surgery. Methods: The clinicopathological features of 317 patients with submucosal gastric cancer, who underwent radical gastrectomy with lymph node dissection at Department of Surgery, Keimyung University School of Medicine from January 2003 to December 2007, were examined retrospectively. The lesions were divided into 3 layers according to the depth of submucosal invasion of the cancer cell (SM1, SM2, and SM3). We analyzed the clinicopathological variables regarding lymph node metastasis. Results: Of the 317 patients, 74 patients (23.3%) had lymph node metastasis. Tumor size, histological type, Lauren classification, depth of invasion, lymphatic invasion, vascular invasion, and perineural invasion showed a positive correlation with lymph node metastasis by univariate analysis. In multivariate analysis, tumor size (≥4 cm vs ＜2 cm, P=0.034 and 2∼4 cm vs ＜2 cm, P=0.043), histological type (P=0.013), and lymphatic invasion (P=0.000) were significantly correlated with lymph node metastasis. Conclusion: Tumor size, histological type, and lymphatic invasion were independent risk factors for lymph node metastasis in submucosal gastric cancer. Minimally invasive surgery, such as endoscopic submucosal dissection may be applied to submucosal gastric cancer with a tumor size less than 2 cm, differentiated histological type, and no lymphatic invasion.