Abstract: PURPOSE: Familial gigantiform cementoma (FGC) is a rare autosomal dominant benign odontogenic tumor. The purpose of this study is to describe the clinical characteristics of FGC in a Chinese family with multiple-affected members. METHODS: Detail screening was conducted on family members of a 13-year-old Chinese male with recent diagnosis of FGC. All family members of the patient were interviewed. Demographic, past medical and surgical histories were collected from family members with history of FGC diagnosis. Clinical information related to the lesions (symptom, age of onset, history of treatment, histological and radiological findings) was obtained. Literature review was also presented in this study. RESULTS: In this study, we found a four-generation Han Chinese family with thirteen affected members with diagnosis of FGC. Eight male patients and five female patients were appreciated in the study. All 13 patients experienced the onset of symptoms at 11-13 years old followed by a rapid and expansive growth phrase at the age of 14-16, and growth suppression phase around age 18 to 20 years old. Eight patients in our series had sustained multiple pathological long bone fractures (average 3-4 x/person) between the age of 13 and 16 years. CONCLUSIONS: The familial history of this case helps to demonstrate that the inheritance pattern of FGC was autosomal dominant. FGC usually presented with three distinctive growth phrases: ①Initial onset; ②Rapid expansion; ③Growth suppression phase.

Key words: Familial gigantiform cementoma, Pedigree, Autosomal dominant inheritance, Long bone fracture