LAUSR

Melanocytic matricoma is a rare, biphasic adnexal tumor. It typical presents as a pigmented papule on the sun-damaged skin of elderly patients. Histopathology shows a dermal nodule composed of basaloid cells, ghost cells and deeply pigmented dendritic melanocytes. The basaloid cells are usually positive for β-catenin and these tumors show overlapping histopathological and molecular features with pilomatricoma. Here we review the literature on melanocytic matricoma and present three new cases. We suggest different terminology to reflect the overlapping features with pilomatricoma, that recognizes that melanocytic matricoma is likely to be a variant of pilomatricoma associated with melanocytic hyperplasia. Although melanocytic matricoma is usually considered benign, malignant transformation has been reported. This highlights the need for increased awareness of this entity. This article is protected by copyright. All rights reserved.