角結膜上皮内癌の組織学的検討

Histopathological findings of conjunctival and corneal intraepithelial neoplasia

要約　目的：角結膜上皮内癌の病理組織所見の報告。症例：81歳女性が左眼の翼状片と上方からの角膜混濁で紹介され受診した。5年前に右眼に翼状片手術を受けていた。左眼に翼状片と上方結膜から角膜に侵入するゼラチン様の半透明な膜があり，上皮内癌が疑われた。組織を切除し，病理学的に検索した。所見：上皮は扁平・肥厚し，異形上皮細胞の増生があり，部位により上皮内癌または異形成を示した。上皮層の基底部がビメンチン陽性，P53はびまん性に陽性で，Ki-67細胞があった。角膜基底膜と実質は正常で，病的変化は上皮層に限定していた。結論：本症例での角結膜上皮内癌は増殖のマーカーが陽性であり，上皮層の基底部分で間葉性の性質を獲得した細胞増殖能が高い組織であると考えられる。

Abstract.　Purpose：To report histopathological findings in a case of conjunctival and corneal intraepithelial neoplasia. Case：An 81-year-old female was referred to us for pterygium and corneal opacity in the left eye. She had received surgery for pterygium in the right eye 5 years before. The left eye showed gelatinous semitransparent membranous lesion infiltrating the upper sector of cornea and conjunctiva. The lesion was resected and was examined histopathologically. Findings：The epithelium was flattened and thickened with proliferation of atypical epithelial cells. Some areas showed findings of intraepithelial neoplasia or severe dysplasia. Basal layer of epithelium was vimentin-positive and diffusely positive for P53. Ki-67 cells were also present. Conclusion：Conjunctival and corneal intraepithelial neoplasia in the present case was positive for proliferation markers. It appears to be a tissue with high proliferative capacity that has acquired mesenchymal properties at the base of epithelial layer.