The histological classification of early gastric cancer (micro-invasive carcinoma of the stomach).

During a 3.5-year period, January 1976 to June 1979, eleven cases of micro-invasive carcinoma of the stomach (early gastric cancer) were detected in 45 gastrectomy specimens having a pre-operative diagnosis of gastric carcinoma. The histological types found in the surgical specimens were highly differentiated (1), moderately differentiated (4), poorly differentiated (3) adenocarcinomas, one specimen had undifferentiated carcinoma, and in the remaining two cases mixed types were found. Multiple lesions were present in five specimens. In ten of the eleven specimens, focal cystic dilatation of the deeper part of the gastric glands were found in areas overlapped by micro-invasive carcinoma and/or in areas overlapped by mucosa showing chronic inflammation. The frequency of cystic dilatation of the gastric gland was much lower in specimens from patients with gastric or duodenal peptic ulcers. Thus, focal cystic dilatation present in negative gastric biopsies should be reported, thereby alerting the referring physician as to the possibility of a gastric malignancy.