顎下腺筋上皮腫の1症例

Myoepithelioma of the Submandibular Gland:Report of a Case

　はじめに

　1943年Sheldon^1）は，57例の唾液腺腫瘍のうち筋上皮細胞由来と考えられる細胞のみからなる3例を認め，これを筋上皮腫と呼んだ。唾液腺腫瘍中，筋上皮腫は1％以下と比較的まれであるとされる。今回われわれは顎下腺に発生した筋上皮腫の1症例を経験したので若干の文献的考察を加え報告する。

Myoepithelioma, first described by Sheldon in 1943, is a rare neoplasm of the salivary glands.

We reported the sixth case of myoepithelioma of the submandibular gland in the Japanese literature. The tumor was surgically removed and was found to be composed of a mixture of two types of myo-epithelial cells-the plasmacytoid and spindle-cell form.

Preoperative diagnosis is quite difficult by radiological images, and it is necessary to suspect of this disease if plasmacytoid cells are recognized in aspiration cytology. As myoepithelioma is more aggressive than pleomorphic adenoma and occasion-ally transforms into malignant myoepithelioma, the tumor should be excised including surrounding healthy tissues.