十二指腸球部に脱出したⅠ型早期胃癌の1例

A Case of Early Gastric Cancer Prolapsed into the Duodenal Bulb

はじめに

　健康診断の目的で外来を受診し，胃X線検査の結果，十二指腸球部腫瘍を疑われ，その後の精査により癌と診断されたが，その原発部位は必ずしも明らかとならず，手術によりはじめて，幽門輪上わずかに前庭部側から発生したⅠ型早期胃癌と判明した症例を経験したので報告する．

　A 66-year-old woman visited our hospital for the routine physical examinaton and was found to have a tumor in the duodenal bulb by x-ray examination. Radiologically the tumor was round, 3cm in diameter, with irregular margins. The filling defect appeared to be a pedunculated mass with its base possibly originating from the pyloric ring. The turnor could not be returned to the stomach by manipulation.

　Gastroscopic examination revealed an irregular epithelium, but the tumor was not identified.

　Duodenalfiberscope also failed to demonstrate the mass, but when the scope was retracted into the gastric space, a part of the tumor was visualized. A diagnosis of adenocarcinoma was made on the basis of biopsy specimen from the lesion. On operation, the tumor was pedunculated on a broad, short stalk which was located in the prepyloric region.

　Pathological diagnosis was adenocarcinoma tubulare localized in the mucosal layer of a part of the tumor.

　When a filling defect is found in the duodenal bulb, a differential diagnosis between a bulbar tumor and a stomach polypoid lesion prolapsed into the bulb is essential. The present case exemplifies difficulties in this differential diagnostic problem.