Giant benign intradermal melanocytic nevus of rapid onset

Benign melanocytic nevi are slowly growing acquired or congenital tumors with varied morphology, commonly encountered in dermatology clinics. Any tumor with rapid clinical growth must be assessed carefully in order to exclude malignancy. We report a woman with a histopathologically benign intradermal nevus that presented as a rapidly evolving large cutaneous mass on the ear. Owing to the discrepancy between the clinical and histopathological findings, an extensive histopathological work-up involving many deeper sections, immunohistochemical stains, and fluorescent in situ hybridization (FISH) analysis was conducted in order to rule out malignancy.