皮膚リンパ上皮腫の1例

A CASE OF CUTANEOUS LYMPHOEPITHELIOMA

　Lymphoepithelioma（Le. と略す）は病理組織学的に，泡沫状，クロマチンに乏しい核を持つ境界不鮮明な原形質の大型な上皮細胞が，索状，塊状又は不規則な島嶼状，時に個々分散してリンパ球の豊富な間質に包埋されている像を特徴としている。本腫瘍は一般に鼻孔後部，欧氏管，軟口蓋，扁桃，喉頭，咽頭，舌根等に発生し，往々にして原発巣は小さく容易に頸部リンパ腺に転移し，時には頭蓋底を侵し，非常に稀に遠隔内臓諸臓器及び皮膚に転移を見る。原発性鼻喉頭部腫瘍の臨床所見が不明瞭であるにも拘らず，頸部リンパ腺L. e. を認める事は屡々であり，多くの学者はこの頸部リンパ腺L. e. を鼻喉頭腫瘍よりの2次的病変又は転移と考えている。

　現在迄，皮膚L. e. に関しては，遠隔転移の一症状として発生した症例，及びリンパ腺，深部軟部組織L. e. からの2次的な皮膚変化の報告があるのみで，定型的な皮膚L. e. は報告されていない。

　Lymphoepithelioma is a relatively rare neoplasm which usually starts on the mucous membrane in the nasopharyngeal region with early metastasis to the cervical Lymph nodes. Metastasis to the skin is exremely rare. According to Dr. Cappell, it is classified into three types, that is, (1) Schmincke's type (2) Regaud's type, and (3) transitional cell carcinoma. Because of its small size and slow growth, it is frequently left unnoticed clinically, which is usually found after the cervical lymph node swelling. All the reported cases of lymphoepithelioma of the skin in literatures belong to either cases of multiple papules or nodules accompanied with metastasis to lymph nodes and other organs or cases of direct skin invasion of the tumor from the primary lesion on the soft palate.

　The authors reported a case of 29-year-old white man with a red tumor on the nasal tip. Histologic specimens gave a diagnosis of cutaneous lymphoepithelioma. The primary lesion in the nasopharyngeal region could not be found.

　The authors emphasized its high sensitivity to x-rays and suggested the possibility of existence of skinoriginated Iymphoepithelioma by its specific and characteristic histologic picture.