A Rare Case of Pilomatrixoma (Calcifying Epithelioma of Malherbe) of Parotid Space Masquerading as Salivary Gland Tumor

Pilomatrixoma is a benign tumor of hair follicle first described as calcifying epithelium (1). It accounts for 1% of all the benign skin tumors (2). It is a slow-growing, firm, dermal or subcutaneous neoplasm, usually measuring fewer than 3 cm in diameter. Pilomatricomas are considered benign; rarely recur after surgical excision (3). However, cases of pilomatrixoma with local recurrence and local invasiveness have been reported in the literature. Microscopically, the tumor is characterized by proliferation of basalloid cell masses arranged haphazardly throughout the tumor with varying degree of cytological atypia with eosinophilliccornified material and abundant shadow cells (4).We hereby present a case of pilomatrixoma arising in a parotid space of a 28 yrold lady. A 28 yr old woman presented to the Department of Oral Medicine and Radiology, NIMS Dental College Jaipur (India) in December 2015 with a chief complaint of a swelling and pain on her left subauricular region, the lesion had disappeared and relapsed several times over one year of duration (Fig. 1). On palpation, it was firm and movable with tenderness. Cervical lymph nodes were non – palpable. Ultrasonography revealed a patchy radiopaque lesion of the parotid space (Fig. 2). Clinical differential diagnoses of pleomorphic adenoma, pilomatrixoma and neurogenic tumors with dystrophic calcification were considered. Informed consent of the patient was obtained. A surgical procedure was performed under general anesthesia. The mass was exposed and removed along with surrounding tissue by extracapsular enucleation. The excised specimen was sent to the Department of Oral and Maxillofacial Pathology NIMS Dental College (Jaipur). The gross specimen showed a firm gritty cut (Fig. 3). Histological examination revealed a peripheral layer of basophilic cells resembling epithelium basaloid cells. The connective tissue stroma was loose and fibrilar (Fig. 4). A central area exhibited collection of numerous nucleus free cells with diaphanous cytoplasm resembling shadow A Rare Case of Pilomatrixoma (Calcifying Epithelioma of Malherbe) of Parotid Space Masquerading as Salivary Gland Tumor