Clinicopathologic Features of the Superficial Spreading Type of Early Gastric Cancer

Abstract

Purpose:The superficial spreading type of early gastric cancer (SSE) has unique features such as its growth pattern and histologic aggressiveness. But its incidence rate is very low, so the clinicopathologic features of SSE are not well known. The aim of this study is to clarify the clinicopathologic features of the superficial spreading type of gastric cancer and we propose an appropriate treatment strategy with the proper treatment modality. Method:A retrospective study was conducted on 894 surgically resected patients with early gastric cancer. The superficial spreading type was defined as a lesion more than 20 cm2. The demographic features and histopathological features were analyzed by using the hospital records. The survival rate was analyzed by the Kaplan-Meier method and the other statistics were analyzed using the chi-square test. Results: For the superficial and common groups, there were no significant differences in the rates of submucosal layer invasion, the histologic types and differentiation and the tumor location. But the ratio of lymph node metastasis was significantly different (P＜0.05). There were some differences concerning the operative methods between the groups. For the superficial spreading type, the portion of total gastrectomy was greater than that of the common type. The average distance between the upper portion of the tumor and the proximal resection margin was shorter for the superficial spreading type than that for the common type (3.78±2.79 cm vs 5.58±2.79 cm, respectively). The 5 year survival rate and the recurrence rate between the two types were not significantly different. Conclusions:Because of the higher rate of lymph node metastasis and the higher rate of an indistinct tumor margin, wide resection with adequate lymph node dissection (D1＋? or more) seems to be a proper operative method for the superficial spreading type of early gastric cancer.