Abstract
It is well known that malignant melanoma arises in a large congenital pigmented nevus. We report a case of basal cell carcinoma arising in a large congenital pigmented nevus.
A 45-year-old woman had a congenital pigmented nevus on the left inguinal region that measured 23×17cm. The patient noticed a red nodule on the nevus in September 2000. When she visited our hospital on August 24, 2001, the dome-shaped nodule 4×4×4cm in size was elastic hard. The left inguinal lymph nodes were swollen. We excised the tumor, and the nevus was doubted to have been a malignant melanoma. Wide excision of the lesion including left inguinal lymph nodes was performed. However, the histopathological diagnosis was basal cell carcinoma, and the lymph nodes revealed no metastasis. [Skin Cancer (Japan) 2004; 19: 120-123]
