画像における鑑別と所見の描出―内視鏡診断―早期胃癌と表層型胃悪性リンパ腫

Endoscopic Discrimination between Early Gastric Cancer and Superficial-Type Primary Gastric Lymphoma

要旨　長径5cm以上のⅡ型早期胃癌と表層型胃悪性リンパ腫の内視鏡像および病理組織所見より，両疾患の内視鏡所見を検討した．内視鏡的鑑別点として病変部の①光沢，②微細血管模様の透見性，③敷石・ひび割れ状粘膜，病変境界部として④ひだの悪性変化，⑤蚕食像，⑥病変範囲，その他の所見として⑦病変が単発か多発かの7項目が重要であると考えられた．早期胃癌では光沢，微細血管模様の透見性が低下しており，ひだの悪性変化や蚕食像を伴うことが多い．一方，表層型胃悪性リンパ腫は病変部の光沢，微細血管模様の透見性は保持され，ひだの悪性変化や蚕食像を伴わない範囲不明瞭な病変として観察される．また，胃癌に比し病変は多発する傾向が認められた．

　To make clear the characteristic features of endoscopic findings in 0-Ⅱ type early gastric cancer over 5 cm in length and superficial-type primary gastric lymphoma, endoscopic images and pathological findings of both diseases were evaluated.

　It seemed that, endoscopically, there were seven factors discernible that were important for discriminating early gastric cancer from primary gastric lymphoma. They were ; i) luster, ii) transparency for capillary network, iii) cobblestone appearance, iv) malignant findings of the folds, v) encroachment of the edge, vi) margin of the lesion, vii) the number of lesions. In case of early gastric cancer, mucosal luster and transparency for capillary network are reduced and they are often accompanied by malignant findings of the folds and encroachment of the edge. On the other hand, superficial-type primary gastric lymphoma retain mucosal luster and transparency for capillary network, and the area is observed as an indistinct lesion. And it is not accompanied by malignant change of the folds and eroded edge. Furthermore, in cases of malignant lymphoma, the lesions tended to be multiple in comparison with the lesions of gastric cancer.