脂腺上皮腫

SEBACEOUS EPITHELIOMA

　今日皮膚腫瘍はきわめて多数に分類されているが，個々の腫瘍はかなり明確に定義されてその病型を比較的容易に理解することができるものが多い。しかしその中でも脂腺上皮腫（sebaceousepithelioma）はなおかなり概念のあいまいさが残されている。これはもちろん本腫瘍の稀有なることにもよると思われる。著者は自験例を報告し本腫瘍の概念について論じてみたい。

A case of sebaceous epithelioma is reported, which was noted on the scalp of an 83-year-old man.

Histologically, the tumor consists of basalioma-like cell masses, which have connections with the surface epidermis. A fairly large number of single and groups of mature sebaceous cells and numerous cystic spaces are noted within the tumor masses. Sebaceous cells and the content of cystic spaces are strongly Sudan III-positive.

The author came to conclusion that sebaceous epithelioma, whose cells are composed of germinative cells and are capable of lipidization, should be classified as a type of adnexal tumors different from basal cell epithelioma biologically, even though the latter may in part exhibit sebaceous cell differentiation and both tumors may occasionally be indistinguishable from each other morphologically.