十二指腸腺腫と癌の病理組織学的診断基準（案）

The Histopathological Diagnostic Criteria for Well-differentiated Epithelial Tumors（Distinction between Adenoma and Carcinoma）

要旨●十二指腸粘膜は正常では小腸型粘膜であるが，異所性胃粘膜や胃上皮化生をしばしば伴い，十二指腸で発生する腫瘍は腸型および胃型形質ともに存在することから，胃と同様の病理診断基準を用いることが可能と考えられる．早期病変の観察に基づく経験から導かれた病理診断基準に，胃上皮性腫瘍の形質発現や細胞増殖動態，遺伝子異常などのエビデンスを加え，構造異型の乏しい高分化上皮性腫瘍の病理組織学的診断基準（腺腫と癌の鑑別診断基準）をここで提唱する．

　The duodenal mucosa a type of small intestine and is accompanied by ectopic gastric mucosa and gastric metaplasia. Duodenal tumors can be of both the intestinal and gastric types. Therefore, histopathologic diagnostic criteria similar to those for the stomach can be used for duodenal tumors. In addition to experience based on observation of early lesions, these criteria have been derived from evidence from a follow-up study, analysis of cell kinetics, genetic events, etc. The histopathological diagnostic criteria for well-differentiated epithelial tumors（distinction between adenoma and carcinoma）have been proposed here.