Ⅱa集簇型を呈した進行胃癌

Advanced Gastric Carcinoma Simulating Ⅱa Aggregated Polypoid Type, a Case Report

　Ⅱa型早期胃癌のなかには比較的稀なものとして肉眼的に小隆起が多数密集し，癌としての領域を占め，集簇性にみられることがある¹⁾．このⅡa集簇型は早期胃癌の性状を示すことが多いが，われわれは術前本症と診断し，術後の検索により，組織像が異型上皮のように分化した分化型腺癌から未分化癌が混在し移行する多彩性の進行癌であった稀な例を経験したので報告する．

　The patient is a 63-year-old woman. There was nothing particular in her familial or past history. Since three years before she felt postprandial dull pain in the epigastrium. She underwent an examination of the upper digestive tract. Physical examination on admission was normal.

　X-ray examination of the stomach after admission revealed in the barium-filled picture unevenness and irregularity on the lesser curvature of the lower body. The greater curvature stretched not too well. In double contrast picture the mucosal surface as a whole was rough and granular, showing clusters of polypoid shadows on the greater curvature of the lower body. Compression picture revealed the same findings.

　Gastrofiberscopy showed hemispheric and nodular clusters of polypoid lesions, in a wide area extending from the greater over to the lesser curvature, centering on the anterior wall of the greater curvature of the lower body over to the angle down to the antrum.

　Gross findings of the excised specimen showed rounded or hemispheric polypoid lesions of various size in an extended area along the greater curvature region from the upper part of the body down to the pyloric antrum. Some of them were confluent, forming a striking protrusion with papillary surface.

　Generally cancer of the protruding type mostly displays differentiated adenocarcinoma, but our case showed variegated patterns, well differentiated adenocarcinoma like atypical epithelium intermixed with undifferentiated adenocarcinoma with appearance of Signet ring cells. They also tended to shift to each other.

　Intestinal metaplasia was predominant in the mucosa of the pyloric antrum, which displayed well differentiated adenocarcinoma, while in the body was seen no intestinal metaplasia, mostly occupied by moderately differentiated adenocarcinoma or poorly differentiated one. This fact seemed to have a relationship with chronic gastritis as a mucosal environment to the development of cancer.