まれな食道良性腫瘍および腫瘍様病変の臨床・病理

Clinicopathological Findings of Benign Esophageal Tumors and Tumor-like Conditions

要旨　食道にみられるまれな腫瘍および腫瘍様病変について自験例の臨床・病理学的所見を呈示するとともに文献的な特徴と診断の要点を加えて概説した．いずれもまれな病変であるため厳密な臨床的診断は困難であるが鑑別の要点として，①黄色調の小結節である黄色腫と食道皮脂腺は粘膜内病変であるため生検による診断が可能で，さらに粘膜内存在部位の違いから内視鏡所見でも鑑別可能と推測された．②fibrovascular polyp，lipomaやinflammatory fibroid polypは肉眼的に類似する大きな粘膜下腫瘍様のポリープであるが形態的特徴から診断は可能で，さらに食道内の発生部位の違いが鑑別の要点と考えられた．③病理学的に一見悪性細胞様の異型を示す食道胃接合部のpseudomalignant erosionや白色調の0-IIa型癌と鑑別を要するepidermizationは，臨床と病理双方がこのような病変の存在に留意することが診断上重要と考えられた．④扁平上皮乳頭腫は一般にポリープ状の病変であるが，まれなものとして側方伸展様の形態を呈するflat-type papillomaが認められた．

　For rare tumors that develop in the esophagus and other tumorous lesions, clinicopathological findings from our own cases, together with features and diagnostic key points given in the literature, were outlined. All are rare lesions and making a precise clinical diagnosis is difficult;but for key points in differential diagnosis, the following can be listed: (1) Both xanthomas, which are small yellowish nodules, and an esophageal sebaceous gland are lesions that develop within the mucosa and therefore can be diagnosed from a biopsy. Due to the difference in the sites of involvement within the mucosa, endoscopic observations are sufficient for differentiation. (2) Fibrovascular polyps, lipoma and inflammatory fibroid polyps are all large submucosal tumor-like polyps that resemble each other under macroscopic observation: Differential diagnosis is possible based on their morphological features. In addition, the sites of involvement within the esophagus may be a key point in differentiation. (3) For pseudomalignant erosion, which seemingly shows malignant cell-like atypia under pathological examination, and epidermization that requires differentiation from 0-IIa tumors of white coloration, it is diagnostically important to note these possibilities in both clinical and pathological examinations. (4) Squamous papilloma commonly presents a polypoid lesion but on rare occasions, flat-type papillomas with lateral extensions have been noted.