Familial gigantiform cementoma with brittle bone disease, pathologic fractures, and osteosarcoma: A possible explanation of an ancient mystery

INTRODUCTIONGigantiform cementomas (GC) constitute one of foursubgroups of cementomas in the classification of theWorld Health Organization [1], a group of benign fibro-osseous lesions of periodontal ligament origin [2]. Adisease related to the cementomas, known as floridosseous dysplasia (FOD), occurs most commonly inmiddle-aged women of African or East-Asian ethnicity[3–6]withameanageatonsetof42years.Ararefamilialformofthecementomas,familialgigantiformcementoma(FGC),isamorphologicallysimilaryetclinicallydistinctentity [7–12], which typically presents in the first orsecond decades of life. It is histologically consistent withthecemento-ossifyingfibromasandresultsinpronouncedfacial asymmetry. It follows an autosomal dominantinheritance pattern with variable phenotypic expression[8–11] although without racial predilection or genderpreference. The disease, generally limited to the facialbones,isconsideredbenignbutitoftenrequiresextensiveresectionandfacialreconstruction[12].Rareextragnathicdisease(‘‘cementomaoflongbones’’)hasbeenpostulatedtobeadistinctentity[13,14],althoughmorethanlikelyitrepresents a disorder of simple bone cysts filled withmaterialmimickingthecementumoftooth[15,16].Toourknowledge, no association of FGC of the jaws with anylong bone disease, benign or malignant, has ever beenreported. We describe four individuals in a single familywith familial gigantiform cementoma, polyostotic dia-physial bone disease, pathologic fractures, and osteosar-coma (OS) in one of the children. We also suggest apossible explanation for the facial abnormalities depictedinthereliefsofthefather(Akhenaten)oftheEgyptianboyking Tutankhamen.PATIENTSPatient 1A 12-year-old African-American female of non-con-sanguineous parents presented with a 5 months history ofswelling and pain in her right knee and a suspecteddiagnosis of OS. She had blue sclerae at birth, confirmedbyaphotographtakenduringinfancy.Attheageof8years,she suffered a fracture of the right tibia following minortrauma (Table I). Her physical exam disclosed aprotuberant jaw (Fig. 1A) and a swollen, tender knee but