隆起型胃癌と鑑別を要する炎症性疾患

Gastric Elevated Lesions Requiring the Differential Diagnosis with Elevated Type Early Gastric Cancer

要旨　胃の多くの炎症性隆起性病変は，その肉眼的特徴から胃癌との鑑別は比較的容易である．これら隆起性病変は腸上皮化生やびらん・潰瘍の再生性過形成性変化として出現することが多く，したがって，腸上皮化生やびらんが出現しやすい前庭部に認めることが多い．腺腫や過形成性隆起病変の中には，Ⅱa型早期胃癌との鑑別に迷う症例もあり，このような症例を鑑別する上で，拡大内視鏡検査により胃粘膜微細模様（fine gastricmucosal pattern；FGMP）を観察することは極めて有用である．悪性病変においては，過形成性粘膜で観察されるD patternの大きさが不揃いで配列が不規則となり，そこにびらんが形成されるとその再生粘膜模様は特有の悪性再生上皮模様（malignant regenerative mucosal pattern；MRMP）を呈することになる．また，悪性新生血管が併存することもあり，これらの所見を観察することでより正確な診断が可能である．

　It is easy to diagnose an elevated lesion due to gastritis by its ordinary endoscopic findings. In the stomach intestinal metaplasia or the regenerative mucosa of the erosion or ulcer often causes these elevated lesions. Such lesions were often found in the antrum. Some adenoma and hyperplastic elevated lesions are difficult to diagnose differentially from early gastric cancers type Ⅱa. At such times it is very useful to perform magnifing endoscopic examination and find out the fine gastric mucosal pattern (FGMP) . FGMP of malignant lesions resembles the D pattern which can be found also in regenerative hyperplastic mucosa, but it is irregular. If there is erosion or ulceration in the malignant lesion, regenerative mucosa comes to form a special pattern which Ⅰ call malignant regenerative mucosal pattern (MRMP). Sometimes, we can find a newly produced malignant vessel accompanied by a malignant lesion. So, if we focus on these special findings of magnifing endoscopy, we can make a more precise diagnosis about such lesions.