Case Discussion
Pilomatrixoma is a benign adnexal tumour of skin involving hair follicles. Sections show a lesion composed of nests of epithelial cells including viable basaloid cells and obsolete 'ghost' cells. Focal calcification is noted. The nests are separated by fibrous tissue containing a foreign body giant cell reaction. The appearance is that of a pilomatrixoma (calcifying epithelioma of Malherbe).
