Skin type spiradenoma of the parotid gland with malignant transformation: report of a case with analysis of the CYLD gene.

A distinctive variant of basal cell adenoma called membranous basal cell adenoma is well recognized in salivary glands. It appears identical to cutaneous cylindroma, hence the synonym dermal analogue tumor. We present a case of a tumor involving the parotid gland that appeared identical to cutaneous spiradenoma. In addition, the lesion had a malignant component identical to basal cell adenocarcinoma. The patient had no features suggestive of Brooke-Spiegler syndrome. Analysis of the CYLD gene revealed polymorphisms. This is the first report of a "dermal analogue tumor" of the salivary gland that resembled a cutaneous spiradenoma and not a cylindroma.