Malignant blue nevus of the parotid gland: A case report.

Abstract

Malignant blue nevus is a highly aggressive tumor arising from a background of benign blue nevus. Extensive review of the medical literature revealed a few reported cases of this transformation from cutaneous origin. We report the first case of blue nevus of the parotid gland and its malignant transformation within this gland. A 62-year-old woman presented to our clinic with sudden onset parotid mass. After a superficial parotidectomy, histologic examination of the specimen was performed. Features compatible with blue nevus with focal region of atypical mitotic activity were evident. The diagnosis of malignant blue nevus was confirmed by immunohistochemical studies. We report the first case of malignant transformation of blue nevus within the parotid gland. We found this lesion to be highly aggressive and to have metastasized shortly after diagnosis.