Prognosis of Early Gastric Cancer: Impact of Lymph Node Metastasis

ABSTRACT

PURPOSE: Early gastric cancer (EGC) is defined as gastric cancer confined to the mucosa or submucosa, regardless of lymph node (LN) metastasis. The prognosis of EGC is more favorable than that of advanced gastric cancer. Due to the variety of prognosis of EGC, in relation to LN metastasis, this study was undertaken to determine the impact of LN metastasis on the survival of patients with EGC, and to aid in planning therapeutic approaches for such patients. METHODS: A retrospective study of 517 patients with EGC, who had undergoing a gastrectomy with lymphadenectomy, between 1990 and 1999 was performed. Stages were classified using the UICC TNM classification (1997). RESULTS: LN metastasis was observed in 67 cases (13.0%). 6.7% (17/288) of the EGC within the mucosa, and 19.0% (50/281) within the submucosa, had LN metastasis. The overall Five-year survival rates (5YSR) of 517 EGC patients was 95.5%, and for the EGC patients in N0, N1, N2 and N3 groups were 98.3, 82.2, 27.8 and 0%, respectively (P<0.001). The 5YSRs for patients with mucosal and submucosal cancers were 98.9 and 92.4%, respectively (P= 0.023), and was poorer in those EGC patients with tumor sizes above 5 cm than in those below 5 cm (5YSR 96.3 and 86.7%, respectively. P=0.020). However, the survival rates for EGC patients did not differ significantly based on the gross and histological types. The 5YSR for EGC patients with stage IA, IB, II and IV were 98.3, 82.1, 40.0 and 33.3%, respectively (P<0.001). LN metastasis and depth of invasion were found to be significant risk factor from the multivariate analysis. CONCLUSION: Based on the results of this study, the significant prognostic factors of EGC were LN metastasis and depth of invasion. Although the prognosis of EGC is favorable, it depends upon the prognostic factors.