The histopathological study showed the malignant transformation of melanocytic nevi with the lymph node metastasis on the right groin.

• 出生后即发现腰骶部有巨大黑素细胞痣,14个月时皮损组织病理检查示,黑素细胞痣恶变并有右侧腹股沟淋巴结转移。