Lymph node metastasis in multiple synchronous early gastric cancer

Background: Although endoscopic resection for early gastric cancer (EGC) is increasingly available, it has not been determined whether indications for endoscopic resection are equally acceptable for multiple EGCs. Objective: To compare the various clinicopathologic factors and risk of lymph node (LN) metastasis between multiple and solitary EGCs. Design: Case-control study. Setting: University hospital. Patients: This study involved 1717 patients with 156 multiple and 1561 solitary EGCs. Intervention: Gastrectomy with LN dissection. Main Outcome Measurements: Incidence of LN metastasis. Results: In multiple EGCs, main lesions had larger tumor size and deeper invasion depth than the accessory lesions (P < .001). The clinicopathologic features of multiple EGCs were similar to those of solitary EGCs with respect to tumor size, depth of invasion, lymphovascular invasion, and incidence of LN metastasis. Importantly, the risk of LN metastasis in multiple EGCs that met the indication criteria for endoscopic resection was not significantly different from that in solitary EGCs. Tumors meeting conventional indications for endoscopic resection had no risk of LN metastasis, whereas tumors meeting expanded indications showed a similar risk of LN metastasis in the two groups. In multiple EGCs, tumor size >= 3 cm and lymphovascular invasion were independent risk factors of LN metastasis. Limitations: Small number of patients with multiple EGCs studied. Conclusion: Multiple EGCs had clinicopathologic characteristics and risk of LN metastasis similar to those of solitary EGCs. Endoscopic resection may be adopted as curative treatment for multiple EGCs that meet indications for endoscopic resection. Further studies are needed to verify the present study results. (Gastrointest Endosc 2011;74:276-84.)