Aggressive pilomatrixoma in a child: a case report.

Calcifying epitheliomas of Malherbe (pilomatrixomas) are benign calcifying tumours that arise from the hair matrix and present as a slow-growing dermal or subcutaneous mass most commonly located in the head and neck. Recurrences after tumour removal are rare. There have been reports in the past of invasive pilomatrixoma in the pre-auricular area (Krausen et al., 1974; Rothman et al., 1976; Sasaki et al., 1976; Arole et al., 1983), as well as other locations such as the right arm (Gromiko, 1927) and the upper back (Lopansri and Mihm, 1980). Two cases were also reported in adults by Weedon et al. in 1980. None of these tumours has occurred in children.