Pilomatricoma is the second most common benign dermal-subcutaneous tumor of the head and neck region, after epidermoid cyst, originating from the outer sheath cells of the hair follicle. It can be easily treated with surgical excision. However, it is a relatively unknown skin lesion to maxillofacial surgeons. Therefore, we report a case of pilomatricoma occuring inferolateral area of the parotid gland in a 54-year-old man; with a review of the relevant literature.

Although the mechanism of the abnormal calcification in the calcifying odontogenic cyst (COC) was not elucidated so far, it has been known that the ghost cells are closely related to the calcification, producing dystrophic globular cementum-like materials, comparable to pilomatricoma in epithelium1). Here, we presented a case of COC occurred in left maxillary canine area of 23 years old female, exhibiting a collection of aberrant ossification admixed with basophilic ghost cells in comparison with seven cases of COC. In the polarizing microscope observation with Masson trichrome stain the present case clearly disclosed the typical birefringence of bony tissue, stained red in von Gieson stain, indicating the collagenous backbone. Some ghost cells showed the features of interdigitating epithelial attachments, empty spaces of nuclei, and reticular basophilic cytoplasms, which were similar to the basophilic ghost cells of philomatricoma. The present case demonstrated the aberrant ossification by basophilic ghost cells in COC similar to the ossification of pilomatricoma