爪甲色素線条を伴った爪部Bowen病

・爪甲中央に色素線条を呈する爪部Bowen病を経験した．

・色素線条は不均一で臨床像からは悪性黒色腫との鑑別を要した．

・爪部Bowen病ではダーモスコピーで爪甲下に角化所見を伴う爪甲色素線条を認め，診断の補助に有用と考える．

（「症例のポイント」より）

　

A case of Bowen’s disease with longitudinal melanonychia

　

Tozawa, Takahisa1）Nakamura, Ayaka2）Kakeda, Masato3）Habe, Koji2）Yamanaka, Keiichi2） 1）Department of Dermatology, Yokkaichi Municipal Hospital 2）Department of Dermatology, Mie University, Graduate School of Medicine 3）Department of Dermatology, Saiseikai Matsusaka General Hospital

　

We reported a case of a 48-year-old male with a pigmented streak on his right middle fingernail. The streak didn't contact the lateral edge of the nail plate. Dermoscopic examination of the nail plate revealed longitudinal black pigmentation with hyperkeratosis. The Hutchinson’s sign was not present. We confirmed a diagnosis of Bowen’s disease by excisional biopsy. Dermoscopy provides valuable information for the diagnosis of subungual Bowen’s disease and aids in the differential diagnosis from nail-unit melanoma.