涙腺良性多形腺腫の免疫組織化学

Immunohistochemical study in pleomorphic adenoma of the lacrimal gland

　涙腺由来の良性多形腺腫で，種々の酵素抗体染色をし，腫瘍とともに摘出された正常涙腺組織と比較した。正常組織では，涙腺上皮細胞はEMA,CEA,keratinに染色され，筋上皮細胞はactinによく染まった。良性多形腺腫では，管腔構造を形成する大型の細胞はEMA,CEA,keratinに陽性で，筋上皮様細胞や紡錘形細胞はactinやvimentinに染まった。一部の紡錘形細胞はS-100蛋白にも陽性であった。ヒアリン変性を示す部位や粘液腫様の部位にみられる類円形細胞はvi-mentinとS-100蛋白に陽性であった。GFAPは平滑筋腫様やヒアリン変性や粘液腫様の部位の一部の細胞に染まった。これらの結果は唾液腺由来の良性多形腺腫の免疫組織化学の結果と類似し，GFAPは多形腺腫の腫瘍関連抗原であるという考えを支持している。

We performed immunohistological studies of pleomorphic adenoma of the lacrimal gland in a 33 -year-old male. In the normal lacrimal gland in the vicinity of the tumor, epithelial cells were positive for EMA, CEA and keratin. Myoepithelial cells stained well with actin. In the adenomatous area, large cells with abundant cytoplasm forming a ductal or glandular structure stained with EMA, CEA and keratin. Myoepithelium-like cells and spindle-shaped cells stained with actin and vimentin. Some spindle-shaped cells were positive for S-100 protein antibody. Round cells in hyalin -degenerated and myxoid areas of the tumor stained with vimentin and S-100 protein. GFAP was present in a small number of cells in the myomatous, hyalin-degenerated and myxoid tumor areas. These findings coincided with immunohisto-chemical features of pleomorphic adenoma of the salivary gland, supporting the concept that GFAP would be a tumor-associated antigen.