微小胃癌の内視鏡診断

Endoscopic Diagnosis of Gastric Carcinoma less than 1cm in Diameter

はじめに

　内視鏡による早期胃癌の発見は，この数年飛躍的に進歩し，その診断の正確さは生検の導入により著しく向上した．しかし，癌病巣がより小さくなり1cm以下の小胃癌になってくると，内視鏡診断はもとより肉眼標本による診断もきわめて困難になってくる．できるだけ小さい状態，できるだけ浅い状態で胃癌を発見するには，どのような点に留意しなくてはならないかを主として内視鏡の立場で論じてみたい．

　Recent increase in the detection of very small carcinoma is chiefly due to the remarkable progress of its diagnostic procedures.

　Of 320 cases of early gastric carcinoma operated on in our hospital, 24 belonged to early cancer less than lcrn in diameter, accounting for about 7% of all early gastric carcinoma. These small gastric carcinoma are divided into the following 3 categories:

(1) single carcinoma

(2) multiple carcinoma

(3) carcinoma existing in a part of ulcer or polyp

　While single carcinoma was found in 8 cases (1 Ⅱa, 1 Ⅱb and 6 Ⅱc), multiple one was seen in 9 (5 Ⅱa, 2 Ⅱb and one each of Ⅱc and Ⅲ), and carcinoma existing in a part of ulcer or polyp in 5 (1Ⅲ and 4Ⅲ+Ⅱc) Conclusion

(1) Differential diagnosis of minute carcinoma is in many instances so difficult and confusing that fiberscopic biopsy is indispensable for the discrimination of minute carcinoma.

(2) IIb type early carcinoma and Ⅱc type small early carcinoma when unassociated with ulcer or ulcer scar is very difficult to detect.

(3) The chance of overlooking a minute carcinorna in multiple cancer is so high that examination must be done very carefully. Especially the importance for endoscopic diagnosis of minute carcinoma is to take pictures clearly and exhaustively to define its form. It is necessary as well to photograph from as many directions as possible.

(4) For the more accurate diagnosis of small changes in the gastric mucosa many new photographic methods should be studied, such as, for example, ultraviolet and fluorescence photography, filter photographying, stereo and magnifying camera, coloring matter scattering and spectrum scaning.