Endoscopic diagnosis of minute gastric cancer of less than 5 mm in diameter.

The accuracy of diagnosis by endoscopic visual and histocytologic examination of minute gastric cancers of less than 5 mm in longest diameter was investigated. Between 1959 and 1981, 55 minute cancers were found in 54 patients at The Center for Adult Diseases, Osaka in Japan: 15 foci were solitary and 40 were associated with other larger gastric cancer. Histologic and/or cytologic confirmation of carcinoma was obtained before operation in 73.3% of cases with a solitary lesion, but in only 7.5% of cases with multiple lesions, for an overall positive result of 25.5%. The diagnostic rate was higher for elevated type and depressed type with converging folds than for flat type and depressed type without converging folds. No cancers of less than 3 mm in longest diameter were correctly diagnosed before operation. Because endoscopic visual diagnosis itself is not sufficiently reliable in determining the nature of the minute lesions, the final diagnosis should be confirmed by endoscopic direct biopsy. However, the first biopsy should be done as carefully as possible, because bleeding in the target area may prevent multiple direct biopsy specimens from being taken. Results also indicate that lesions which could not be diagnosed before operation could not be endoscopically inspected. Therefore, endoscopic detection and subsequent accurate biopsy of suspicious lesions is very important for diagnosis of minute gastric cancer.