Diagnosis of early gastric cancer seen as less malignant endoscopically.

In order to make the endoscopic diagnosis of early gastric cancer more accurate, we determined the endoscopic and clinicopathological characteristics of the 129 cases of early gastric cancer with less malignant appearance among the 978 cases of the disease with a solitary lesion detected at the National Cancer Center Hospital during the period between 1962 and 1981. According to findings required to make a differential diagnosis, the endoscopic appearance of the 978 cases were divided into the following four groups: 170 cases of polypoid, 587 of ulcerative, 119 of gastritis-like and 102 of advanced cancer-like. Among the four groups, the frequency of cases with less malignant appearance was quite high in the gastritis-like group. The lesion in this group was defined as the cancerous lesion which shows only superficial mucosal abnormality, not associated with any polypoid or ulcerative components. Chronologically, it has been rapidly increasing in recent years. These two paradoxical phenomena in the gastritis-like group, that is, "high frequency of less malignant appearance" and "increase in number of cases" not only indicate the inadequacy of the conventional criteria for the recent cases but also show that the gastritis-like malignancy is detectable. New additional endoscopic criteria for the gastritis-like malignancy, for example, irregular margin of the shallow mucosal depression, disproportion of the mucosal granularity, irregularity on the erythematous change and discoloration are essential in order to detect much more cases with less malignant appearance.