[Clinicopathological study of minute cancer of the stomach].

Nineteen patients with solitary minute carcinoma (single cases) and 16 with foci of minute cancer, found as a component of multiple early gastric carcinoma (multiple cases) were studied. The results were as follows; 1) The histological type of the single cases was the differentiated type in 95%. 2) All lesions of the multiple cases were mucosal invasive carcinoma, while 16% of the single cases (3/19) had submucosal invasive carcinoma. 3) As for the distribution of the single and multiple cases according to the surrounding mucosal atrophy, the single eases were in the pyloric gland zone, the multiple cases in the intermediate zone.

[Detection of resection line in early gastric cancer].

In patients with multiple gastric cancer and superficial spreading type gastric carcinoma (abbreviated as S.S.C.) accompanied by IIb, the remnant stomach is sometimes cancer positive. Our study population consisted of 44 patients with multiple early gastric cancer and 63 patients with depressed type S.S.C. The gastric mucosa was classified into 3 types according to the surrounding mucosal atrophy, 1) pyloric gland zone, 2) intermediate zone, 3) fundic gland zone. All lesions of multiple early gastric cancer and S.S.C. were located in the pyloric gland zone or the intermediate zone. The depressed type S.S.C. did not invade the fundic gland zone. Therefore, knowledge about the extend++ of surrounding mucosal atrophy is required for the proper diagnosis of early gastric cancer and the surgeon must recognize the relationship between the glandular border line and resection line.

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

When 58 minute gastric cancers less than 5 mm in diameter from 55 patients were classified into 22 of the single group (minute gastric cancer alone) and 36 of the multiple group (associated with other large gastric cancers), the preoperative correct diagnostic rate by x-ray was 22.7% and 11.1% in the single group and in the multiple group, respectively, with a total rate of 15.5%. The diagnostic rate by endoscopy, aided by endoscopic biopsy, was 95.5%, 13.9%, and 44.8%, respectively. Therefore, it appears that endoscopy and endoscopic biopsy are most efficient diagnostic tools for the detection of such minute gastric cancers. Since the detection of the depressed type (IIc) of minute gastric cancers is considered most significant because of their frequent submucosal invasion, their characteristic endoscopic findings are emphasized: (1) irregular and polygonal shape, (2) distinct depression, (3) clear demarcation, (4) nodular margins, and (5) moth-eaten appearance and abrupt thinning of the mucosal folds.

Minute gastric cancers less than 5 mm in diameter.

Minute gastric cancers with maximum dimensions of less than 5 mm were studied clinicopathologically. There were 49 intramucosal cancers among 46 patients and nine submucosal cancers among nine patients. No lymph node metastasis was found. Macroscopically, eight (13.8%) were evaluated, 12 (20.7%) were flat, and 38 (65.5%) were depressed. Most submucosal cancers were of the depressed type (8/9, 88.9%). Classification of cancers according to association with other large cancers into single group (22 cases) and multiple group (33 cases) revealed that (1) the majority of the minute gastric cancers (20/22, 90.9%) in the single group were the depressed type and (2) submucosal cancers in the single group were 8/22, accounting for 36.4%, a much higher incidence as compared with 1/36 (2.9%) in the multiple group. These facts indicate that gastric cancers should be detected when they are about 5 mm in maximum dimension and before they invade beyond the submucosal layer, especially in single and depressed type.