自然退縮を認めたproliferative nodulesを伴った神経皮膚黒皮症

・出生時より色素斑から隆起する結節を伴った神経皮膚黒皮症を経験した． ・結節は一部融合し腫瘤を形成，潰瘍を伴っており悪性黒色腫と鑑別を要したが，病理組織学的所見からproliferative nodules（PNs）と診断した． ・慎重に経過観察を行ったところ腫瘤の自然退縮を認めた． ・PNsは新生児〜乳幼児期に巨大色素性母斑の病巣内に生じる結節性病変であり，しばしば悪性黒色腫との鑑別が問題となる． （「症例のポイント」より）

A case of neurocutaneous melanosis with proliferative nodules showing spontaneous regression

Mochimaru, Naoko1）Tanaka, Ryo1）Hikosaka, Makoto2）Kiyotani, Chikako3）Niizeki, Hironori1）Yoshida, Kazue1） 1）Department of Dermatology, National Center for Child Health and Development 2）Department of Plastic Surgery, National Center for Child Health and Development 3）Children’s Cancer Center, National Center for Child Health and Development

Abstract We report a case of a 1-month-old girl who had giant congenital nevus (bathing-trunk nevus) on her trunk and many black spots all over her body since birth. In addition, numerous blackish-brown, elevated, and elastic hard skin nodules with ulcers were found on her back. Magnetic resonance imaging revealed melanosis in the brain and spinal cord, and this girl was diagnosed as having neurocutaneous melanosis. Pathological examination of the back mass showed proliferation of the nevus cells in the epidermal dermis, and no malignant cells were observed. We carefully followed up the patient for 4 years. During the course, the mass gradually flattened and softened. Based on the histological features and clinical course, we diagnosed the case as proliferative nodules．