Analysis of Prognostic Factors and Outcome of Early Gastric Cancer with and without Lymph Node Metastasis

ABSTRACT

PURPOSE: Lymph node (LN) metastasis and depth of invasion are known to be prognostic factors in early gastric cancer (EGC). This study was designed to determine the clinicopathological features of EGC with and without LN metastasis and an appropriate procedure for EGC. METHODS: The authors retrospectively reviewed 489 patients with EGC who underwent curative resection with LN dissection between January 1990 and December 1997 at the Department of Surgery, Keimyung University Dong San Medical Center. The authors divided the 489 patients into two groups. Group 1 EGC with LN metastasis, Group 2 EGC without LN metastasis. We analyzed and compared the clinicopathologic features (age, sex, tumor location and size, gastric resection and LN dissection, macroscopic type, depth of invasion, histological type, Lauren classification and lymphatic and vascular invasion) of the two groups. RESULTS: The incidence of EGC among all gastric cancer was 29.1% and increased annually (19.1% in 1990, 31.5% in 1994 and 40.2% in 1997). The incidence of LN metastasis was 16.2% (79/489) with 7.2% in mucosal cancer and 26.7% in submucosal cancer. Univariate analysis of 12 prognostic factors revealed only 4 factors, that were statistically significant depth of invasion, tumor size, histologic type and lymphatic invasion. Multivariate analysis of these 4 significant prognostic factors did not yield significant results but the risk ratio revealed depth of invasion, tumor size, histological type and lymphatic invasion occurred in order of decreasing frequency. The five-year survival rate of EGC was90.83% (91.82% in EGC with LN metastasis and 85.80% in EGC without LN metastasis, p=0.0242). The relationship between the depth of invasion, macroscopic type, tumor size and LN metastasis revealed there was no LN metastasis in tumors of less than 2.0 cm in size in the elevated type (both in mucosal and submucosal cancer) and less than 1.0 cm in the size in the depressed type (only in mucosal cancer). CONCLUSION: Gastrectomy without LN dissection can be applied for EGC less than 2.0 cm in size in elevated types (both in mucosal and submucosal cancer) and less than 1.0 cm in size in depressed types (only in mucosal cancer). Conventional gastrectomy with LN dissection is recommended in other early gastric cancer.