十二指腸における隆起性病変の拡大観察とその診断学的意義

Significance of Magnifying Endoscopy in Diagnosis of Duodenal Elevated Lesions

要旨　十二指腸における各種の隆起性病変(直径1cm以上)41例を対象に，拡大内視鏡検査を施行した．それらの病変を診断する際の観察ポイントと拡大内視鏡の診断学的意義は，以下のようにまとめることができた．①拡大内視鏡では絨毛の外形とサイズ(正常絨毛との比較)を把握することが最も重要である．②拡大内視鏡が最も有用な疾患は，Brunner腺腫と胃上皮化生による隆起性病変である．③腺腫と早期癌の鑑別のための拡大内視鏡の有用性の有無については，現時点においては明らかでない．④腺腫の絨毛の白色化は，吸収上皮細胞内の脂肪粒の蓄積によるものと考えられるが，拡大内視鏡診断との関連性については今後の課題である．

　Forty-one cases of duodenal elevated lesions (more than 1 cm in diameter) were examined by magnifying endoscopy. Of the 41 cases, 5 were Brunner's gland cyst, 2 were lipoma, 1 was carcinoid tumor, 5 were Brunner's gland hyperplasia, 8 were lymphangioma, 7 were mucus secreting polyp, 5 were gastric epithelial metaplasia, 7 were adenoma and 1 was carcinoma. Endoscopic observation was focused on the shape and size of villi in these lesions. The significance of magnifying endoscopy for endoscopic diagnosis of these lesions was summarized as follows ;

　1. Magnifying endoscopy is most useful in diagnosis of Brunner's gland hyperplasia and elevated lesion due to gastric epithelial metaplasia.

　2. The usefulness of magnifying endoscopy for discrimination of adenoma from early-stage carcinoma is uncertain.

　The relationship between the whitish villous color in adenoma and the existence of lipid in the duodenal mucosa was examined histologically in 4 cases of duodenal adenoma. Results indicated that accumulation of absorbed lipid in absorptive cells at the tip of the villi made the villous color whitish.