悪性黒色腫を生じた多発性境界母斑

MULTIPLE NEVOCELLULAR NEVI (JUNCTIONAL TYPE) DEVELOPED TO MALIGNANT MELANOMA

　境界母斑は皮膚および皮膚粘膜移行部において，どこにでも分布しうるが，多くの場合，複合母斑の初期発展段階としての比較的一時的な状態であり，小児にのみ見られ，例外的な部位は手掌，足蹠および陰部で，そこでは小児とともに成人でも，組織学的にみられる（母斑）細胞型母斑の普通の病型であるとされている．

　最近，著者らは27歳男子で，悪性黒色腫とともに多発性散在性に境界母斑が存在した1例を経験した．すなわち，患者のほぼ全身に多数の点状色素斑を認め，体部，四肢についてはすべて，合計108の点状色素斑を組織学的に検索したところ，その88が境界母斑であり，またlentigo simplexから境界母斑の発生を思わせる所見も得た．患者は受診の3年前に悪性黒色腫を生じたと同部に，同様点状色素斑が存在したことは写真上明らかであつた．

Junctional type of nevocellular nevus, especially multiple ones on other parts than palms, soles and genitaliae are rare in adults. A case of this disease disseminated on the entire body surface and accompanied with malignant melanoma in a 27-year-old man was reported.

About 80% of 108 melanized spots from the trunk and extremities were proved to be the junctional type histologically. Some of the junctional type nevi showed the picture of lentigo simplex with the budding phe-nomen of the epidermis.

The malignant melanoma was a tuberous type on the right medial retro-malleolar region, where a small spot was proved to have existed by the picture taken 3 years before. This melanoma might have developed from one of the freckles, refering to the picture and histologic jindings.