3Kaddu S, Soyer H P, Hodl S, et al. Morphological sta- ges of pilomatricoma[ J]. Am J Dermatopathol, 1996, 18 (4) :333-338.
4Chan E F, Gat U, Mcniff J M, et al. A common human skin tumour is caused b y activating mutations in beta- catenin[J] Nat Genet, 1999, 21 (4):410-413.
5Hwang J Y, Lee S W, Lee S M. The common ultrasono- graphic features of pilomatricoma [J] Ultrasound Med, 2005, 24(10) :1397.
6Kawakami M, Yoshimura K, Tanaka H, et al. Two cases of pilomatrixoma in the cheek[ J ]. Bull Osaka Med Coil, 2004, 50(1-2):13.
7Whittle C, Martinez W, Baldassare G, et al. Pilomatrico- ma: ultrasound diagnosis[J]. Rev Med Chil, 2003, 131 (5) :735.
8Thomas R W, Perkins J A. Surgical excision of pilomatri- coma in head and neck: a retrospective review of 26 cases [J]. Ear Nose Throat J, 1999, 78(8) :541-544.
9Black S J, Marple B F, Vuith F. Multiple giant piloma- tricoma of the head and neck [ J ]. Head Neck Surg, 1993, 109(3):541-547.
10Julian CG, Bowers PW. A clinical review of 209 pilomatricomas. J Am Acad Dermatol, 1998,39 : 191
