十二指腸非乳頭部隆起性病変─腫瘍様病変

Clinical and Endoscopic Features of Tumor-like Lesions of the Duodenum

要旨●十二指腸非乳頭部腫瘍様病変の臨床像と内視鏡像を明らかにする目的で，当科で内視鏡的切除または生検により病理組織学的に診断された腫瘍様病変を対象として，その臨床的特徴を遡及的に検討した．内視鏡的切除によりBrunner腺過形成・過誤腫4例，胃腺窩上皮過形成・胃腺窩上皮型過形成性ポリープ6例，Peutz-Jeghers型ポリープ4例が診断されていた．Brunner腺過形成・過誤腫4例中3例はSMT様の形態を呈し，2例は表層に胃腺窩上皮を伴っていた．胃腺窩上皮過形成・胃腺窩上皮型過形成性ポリープ6例は隆起型や有茎性の形態を呈し，6例中4例に胃底腺組織を認めた．生検に基づいて異所性胃粘膜44例，異所性膵2例が診断されていた．異所性胃粘膜は44例中40例が十二指腸球部に存在し，29例が顆粒状小隆起の集簇の形態を呈していた．近年，腫瘍様病変は腺癌の前駆病変ないし胃型腫瘍の発生母地としても注目されつつあるが，隆起性病変の表面に島状に存在する胃腺窩上皮を通常あるいは画像強調内視鏡下に確認することが，腫瘍様病変の拾い上げ診断ないし内視鏡的鑑別診断に有用となる可能性がある．

　This study aimed to clarify the clinical features and endoscopic images of tumor-like lesions of the duodenum. We retrospectively examined the clinical features of tumor-like lesions histopathologically diagnosed by endoscopic resection or biopsy at our department. In total, four cases of Brunner's gland hyperplasia and hamartoma, six cases of crypt hyperplasia/hyperplastic polyps, and four cases of Peutz-Jeghers type polyps were diagnosed using endoscopic resection. Of the four cases of Brunner's gland hyperplasia/hamartoma, three exhibited submucosal tumor-like morphology and two cases exhibited gastric-like mucosa on the surface layer. In the six cases of crypt hyperplasia/hyperplastic polyps, we observed protruding or pedunculated morphology ; of them, four showed gastric fundic glands. In addition, we diagnosed 44 cases of ectopic gastric mucosa and two cases of ectopic pancreas based on the histopathology of the biopsy samples. Of them, we observed ectopic gastric mucosa in the duodenal bulb in 40 cases, and 29 cases exhibited morphology of protruding granular aggregation. In recent years, tumor-like lesions have gained attention as a precursor lesion of adenocarcinoma or as a lesion where gastric-type tumor originates. This would confirm islands of gastric epithelium on the surface of the protruding lesions under regular endoscopy or image-enhanced endoscopy and, thus, may be useful for the detection and endoscopic differential diagnosis of tumor-like lesions.