抄録
A gastric cancer is defined as early cancer when the cancerous invasion is limited within the mucous and submucous layers. Early gastric cancer is classified in 5 types. This report describes the endoscopic differencial diagnosis, limitation of endoscopic diagnosis of protruded type and elevated type of early gastric cancer.
Material: 102 cases of adenomatous polyp, 16 cases of submucosal tumor, 28 cases of protruded type of early cancer, 6 cases of elevated type of early cancer, and 10 cases of (III+IIc) type of early cancer were obtained in our hospital from 1962 to 1966.
Results. (1) protruded type is a polypoid carcinoma. If examination with gastrocamera is carried out properly the risk of missing such a polypoid lesion is very low. However differentiation of benign and malignant polyps is often difficult. 72% of polypous lesion more than 2cm in diameter were malignant. (2) Uneveness of the surface, broad base hemorrhage and central depression suggest malignant. (3) Redness of the surface is observed not only in malignant polyp but also in a benign one. Fading color and paleness of surface are found sometimes in malignant. (4) Polyp smaller than 2cm with stalk is almost benign. (5) Irregular, map-like, warm-like tumor is almost malignant, but round, oval tumor is benign. (6) II a type is an early carcinoma of low plateau type, the height of which is less than the thickness of gastric mucosa. II a type in its pure form is rare but found commonly in combined types (IIa+IIc). Endoscopic demonstration of type II a carcinoma is easy, for the elevation become distinct with inflation of the stomach with air. Differential diagnosis of this type is sometimes very much confusing. Fiberscopic biopsy are requested for the questionable cases. (8) Gastric polyposis was almost benign but in a case with diffuse polyps mucosal cancer was found. (9) It is difficult to differentiated whether malignant or benign but we confidently expect further advances in this field in the near future.
