術前にⅡa＋Ⅱc型早期胃癌と診断した異型上皮の1例

Atypical Epithelium Preoperatively Diagnosed As an Early Gastric Cancer Type Ⅱa＋Ⅱc, Report of a Case

　胃の良性・悪性境界領域病変である異型上皮（atypical epithelium）は肉眼的，組織学的に早期胃癌との鑑別が難しいが，隆起型異型上皮に関しては，X線・内視鏡診断の進歩と生検の普及によってほぼ正確な診断がなされている．しかし平坦型・陥凹型異型上皮や隆起と陥凹が混在している異型上皮については，症例も少なく，鑑別診断も更に難しくなり，癌と診断されて手術される例も少なくない．

　今回，内部に陥凹を有する隆起性病変を胃前庭部に認め，Ⅱa＋Ⅱc型早期胃癌と診断して手術を行い，術後の病理組織学的検索で異型上皮であった1症例を経験した．この症例の診断過程を中心に検討したので報告する．

　A 51-year-old man visited our hospital for a detailed examination after an abnormality was detected in his stomach at a gastric mass survey.

　The double contrast and the compression study of the stomach showed a round and slightly elevated lesion, with irregularly-shaped depression in its center, on the greater curvature of the antrum. Endoscopy revealed an irregularly-shaped depression surrounded by slightly elevated lesion without erosion or redness on its surface.

　With preoperative diagnosis of an early gastric cancer of type Ⅱa＋Ⅱc, gastrectomy was carried out. By its histopathological examination, it was diagnosed as atypical epithelium.

　We reviewed macroscopic diagnosis of this case, and concluded as follows:

　1. It is important to take an enface picture in double contrast study or in various hard compression study to express the surface of the lesion.

　2. The absence of erosion on the surface of the lesion suggested its benignancy.

　3. An accurate biopsy with enough and undamaged specimen is important to diagnose a lesion histologically.