Clinicopathologic characteristics of early gastric cancer in Korea

Gastric cancer is the most common cause of cancer related death in Korea. Early gastric cancer (EGC), confined to mucosa or submucosa, regardless of lymph node metastasis, is known to have a favorable prognosis. From 1976 to 1995, four thousand nine hundred and twenty eight gastric cancer patients underwent operation at the Severance Hospital, Yonsei University, College of Medicine, Seoul, Korea. Of these, 1,117 patients (22.6%) were diagnosed as EGC and underwent curative operation. Clinicopathologic characteristics were reviewed and survival data was analyzed. The proportion of EGC has increased during the last two decades, from 14.9% during 1976-1985 to 25.8% for 1986-1995. EGC has a wide age distribution range from the thirties to the sixties, with highest incidence in the sixties. The male to female ratio is 1.8:1, without any significant change in last two decades. Most lesions are located in the lower third of stomach (52.3%), and the lesser curvature (52.2%) was the most frequent site in the transverse axis. Macroscopically, the depressed type was the most common (66.1%) followed by the elevated, flat and mixed types, in that order. Tumor confined to the mucosa layer was seen in 52.5%, and lymph node involvement in 11.7%. The depth of tumor invasion correlated with tumor size and regional lymph node involvement. On histopathologic examination, signet ring cell type accounted for 29.6% of all EGCs. Overall 5-year survival rate was 92.7% and the presence of lymph node metastasis significantly affected survival (84.6% versus 96.2%) (p<0.05). In conclusion, the proportion of EGC, in terms of the gastric cancers operated upon, has been increasing in Korea over the last two decades. The introduction of active diagnostic approaches and diagnostic modalities could improve early diagnosis and the cure rate of gastric cancer in Korea.