Preoperative Predictive Factors of Lymph Node Metastasis in Early Gastric Cancer

ABSTRACT

PURPOSE: Early gastric cancer (EGC) is defined as gastric cancer confined to the mucosa or submucosa, regardless of lymph node (LN) metastasis. LN metastasis is the most important factor in the treatment of EGC. If LN metastasis is predicted before or during surgery, function preserving surgery, such as endoscopic mucosal resection, laparoscopic partial gastrectomy, and pylorus preserving gastrectomy, without radical LN dissection, can be applied. This study was undertaken to determine the factors affecting LN metastasis and to aid in planning therapeutic approaches for such patients. METHODS: A retrospective study was performed on 1, 203 patients with EGC, who had undergoing a gastrectomy, with lymphadectomy, between 1990 and 2003 at the Keimyung University, Dongsan Medical Center. We analyzed tumor size, depth of invasion, macroscopic, and histologic types and lymph node metastasis using preoperative endoscopy and radiological findings. RESULTS: The incidence of EGC of all gastric cancer has increased annually. Of the 1, 203 patients, 54.2% and 45.8% had mucosal and submucosal cancers, respectively. The incidences of LN metastasis were 4.0% and 23.0% in mucosal and submucosal cancers, respectively. There was no LN metastasis in mucosal cancer, with a tumor size of less than 1 cm (0/169). In the elevated and flat types, the size of the tumors were between 1 and 2 cm, and there was no LN metastasis (0/40), (0/28), but with the depressed type there was an LN metastasis rate of 6.1%. In the well differentiated type, there were 0.5 (1/193) and 12.9% (11/85) LN metastasis in the mucosal and submucosal cancers, respectively. CONCLUSION: A gastrectomy without LN dissection can be applied for EGC less than 1 cm in size and to all well differentiated types of mucosal cancer. Also, it can be applied to elevated and flat EGC types less than 2 and 1 cm in size in mucosal cancer and less than 1 cm sized in submucosal cancers, respectively. A conventional gastrectomy, with LN dissection, is recommended in other EGC types.