Pilomatrix carcinoma of the nose: Clinical and dermoscopic presentation

A 69-year-old man presented with a smooth dome-shaped reddish nodule, 1.4 cm in diameter, which had rapidly arisen on the nose over the previous 3 months (Fig 1). Dermoscopy found a prevalent vascular pattern characterized by arborized vessels surmounting the lesion. Homogeneous structureless purple/blue areas covered most of the surface. Blotches of various sizes were asymmetrically distributed: the largest presented a white central portion and a yellowish color in the periphery, the smaller ones showed shades of yellow/orange (Fig 2). The lesion was excised. Histology found an expansile growth of variously sized aggregations of basaloid cells with high mitotic activity surrounded by desmoplastic stroma. Foci of cornified material containing shadow cells were observed within the aggregations of basaloid cells, along with geographical necrosis (Fig 3). Pilomatrix carcinoma (PC) was diagnosed. Key messagePC is a rare dermo-hypodermic neoplasm originating from the hair matrix. PC should be suspected in rapidly growing nodular lesions, arising in the head and neck region, presenting simultaneously white-yellowish blotches and arborizing vascular structures. White-yellowish blotches are observed in both PC and benign pilomatricoma because of the presence of calcifications/cornified material. On the contrary, arborizing vessels have never been detected in pilomatricoma (Fig 4). They also differ from the branched arborizing vessels of basal cell carcinoma, extending superficially without interruption and creating an unfocused network covering the entire surface. The excision of doubtful lesions is mandatory especially in adults, because PC is locally aggressive with a tendency to metastasize. PC is a rare dermo-hypodermic neoplasm originating from the hair matrix. PC should be suspected in rapidly growing nodular lesions, arising in the head and neck region, presenting simultaneously white-yellowish blotches and arborizing vascular structures. White-yellowish blotches are observed in both PC and benign pilomatricoma because of the presence of calcifications/cornified material. On the contrary, arborizing vessels have never been detected in pilomatricoma (Fig 4). They also differ from the branched arborizing vessels of basal cell carcinoma, extending superficially without interruption and creating an unfocused network covering the entire surface. The excision of doubtful lesions is mandatory especially in adults, because PC is locally aggressive with a tendency to metastasize.