非乳頭部十二指腸腫瘍様病変の拡大内視鏡診断

The Latest Magnified Endoscopic Features of Superficial Non-ampullary Duodenal Epithelial Tumor-like Lesions

要旨●非乳頭部十二指腸腫瘍様病変の内視鏡所見/拡大内視鏡所見を明らかにすることを目的として，当科において内視鏡的切除標本の検討により病理組織学的に腫瘍様病変（異所性胃粘膜，Brunner腺過形成，胃腺窩上皮型過形成性ポリープ，Peutz-Jeghers型ポリープ）と診断した症例を対象として抽出し，遡及的にその臨床所見と内視鏡所見/拡大内視鏡所見を検討した．内視鏡的切除により異所性胃粘膜5例，Brunner腺過形成・過誤腫13例，胃腺窩上皮型過形成性ポリープ12例，Peutz-Jeghers型ポリープ6例が診断されていた．拡大観察所見はdemarcation lineを胃腺窩上皮型過形成性ポリープで全例に認めたが，異所性胃粘膜60.0%，Brunner腺過形成では22.2%にとどまった．dense patternは異所性胃粘膜40.0%，胃腺窩上皮型過形成性ポリープ50.0%にみられたが，Brunner腺過形成では22.2%であった．腫瘍様病変の中で，胃腺窩上皮型過形成性ポリープ，異所性胃粘膜とBrunner腺過形成は表面全体ないし一部が胃腺窩型上皮に被覆されるため，NBI観察では背景粘膜に比してbrownishに見える．特に胃腺窩上皮型過形成性ポリープ，異所性胃粘膜は拡大観察でdense patternを呈する頻度が高く，NBI拡大観察が腫瘍様病変の診断に有用と考えられた．

　This study aimed to elucidate the endoscopic features/magnified endoscopic features of superficial non-ampullary duodenal epithelial tumor-like lesions. The endoscopic features of superficial non- ampullary duodenal epithelial tumor-like lesions（ectopic gastric mucosa, Brunner's gland hyperplasia, gastric foveolar hyperplastic polyps, and Peutz−Jeghers polyp）histopathologically diagnosed by endoscopic resection at our department were retrospectively examined. A total of 5 cases of ectopic gastric mucosa, 13 cases of Brunner's gland hyperplasia/hamartoma, 12 cases of gastric foveolar hyperplastic polyps, and 6 cases of Peutz−Jeghers polyps were diagnosed via endoscopic resection. The magnified endoscopic features revealed a demarcation line in all cases of gastric foveolar hyperplastic polyps, but only 60% and 22.2% in ectopic gastric mucosa and Brunner's gland hyperplasia, respectively. A dense pattern was observed in 40% of ectopic gastric mucosa, 50.0% of gastric foveolar hyperplastic polyps, and only 22.2% of Brunner's gland hyperplasia. Among the superficial non-ampullary duodenal epithelial tumor-like lesions, gastric foveolar hyperplastic polyps, ectopic gastric mucosa, and Brunner's gland hyperplasia exhibited a more brownish color compared to the duodenal mucosa in the narrow-band imaging, which was attributed to the entire surface or part of the surface being covered by the gastric foveolar epithelium. In the diagnosis of tumor-like lesions, the narrow-band imaging magnification may be useful because gastric foveolar hyperplastic polyps and ectopic gastric mucosa frequently show a dense pattern.