title: Intraosseous pilomatricoma: a possible rare skeletal manifestation of Gardner syndrome.
abstract: Here we report a case of intraosseous pilomatricoma in a patient with Gardner syndrome. A 17-year-old boy with a family history of Gardner syndrome and multiple cutaneous epidermoid cysts presented with pain in the region below the knee of the left leg. Plain radiographs displayed a well-circumscribed eccentric lesion of mixed radiolucent and radiopaque density within the diaphysis of the left proximal tibia. By magnetic resonance (MR) imaging, the lesion appeared as a low intensity lesion in T1-weighted images and a heterogeneous high intensity lesion with a low-signal radiation pattern on T2-weighted images. Gadolinium enhancement was observed partially within the lesion and intensely in the lesion rim. After curettage, histological examination revealed a massive accumulation of keratinous material with epithelial nests that displayed both epidermal and trichilemmal keratinization with basaloid and shadow cells and with metaplastic ossification. These features confirmed a pathological diagnosis of intraosseous counterpart of pilomatricoma. In the context of this patient's skin lesions, intraosseous pilomatricoma may be a rare skeletal manifestation of Gardner syndrome.
authors.affiliation: Department of Pathology and Laboratory Medicine, National Center of Neurology and Psychiatry, Kohnodai Hospital, Kohnodai 1-7-1, Chiba, Ichikawa 272-8516, Japan. k3301@ncnpk.hosp.go.jp
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ishida
authors.forename: Satoshi
authors.initials: S
authors.lastname: Abe
authors.forename: Yuji
authors.initials: Y
authors.lastname: Miki
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Imamura
mesh_terms: D000293:Adolescent; D001859:Bone Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D003287:Contrast Media / Q000008:administration & dosage; D003937:Diagnosis, Differential; D004814:Epidermal Cyst / Q000150:complications / Q000175:diagnosis / Q000601:surgery; D005736:Gardner Syndrome / Q000150:complications*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D018296:Pilomatrixoma / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D011859:Radiography; D035583:Rare Diseases; D013977:Tibia / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery
chemical_list: D003287:Contrast Media