Giant benign intradermal melanocytic nevus of rapid onset.

Benign melanocytic nevi are slowly growing acquiredor congenital tumors with varied morphology,commonly encountered in dermatology clinics. Anytumor with rapid clinical growth must be assessedcarefully in order to exclude malignancy. We report awoman with a histopathologically benign intradermalnevus that presented as a rapidly evolving largecutaneous mass on the ear. Owing to the discrepancybetween the clinical and histopathological findings,an extensive histopathological work-up involvingmany deeper sections, immunohistochemical stains,and fluorescent in situ hybridization (FISH) analysiswas conducted in order to rule out malignancy.