title: The variability and complexity of ameloblastoma: carcinoma ex ameloblastoma or primary ameloblastic carcinoma.
abstract: Ameloblastoma is characterized by slow-growing, local invasiveness and high incidence of local recurrence. It usually presents with a benign histological appearance. However, ameloblastoma occasionally demonstrates a clinical course that is characteristic of malignant transformation. Here, we present a case of ameloblastoma with an aggressive clinical course, including multiple recurrences, a short disease-free interval, pulmonary metastasis and extensive skull-base infiltration. With a careful re-evaluation of the histology and cytology of the specimens of primary and recurrent ameloblastoma in 2006 and 2007, malignant transformation was observed and carcinoma ex ameloblastoma was ultimately diagnosed.
authors.affiliation: Department of Dentomaxillofacial Radiology, Affiliated Stomatology Hospital of Medical School, Nanjing University, Zhong Yang Road 30, Nanjing, China.
authors.forename: Zitong
authors.initials: Z
authors.lastname: Lin
authors.forename: Fei
authors.initials: F
authors.lastname: Chen
authors.forename: Tiemei
authors.initials: T
authors.lastname: Wang
authors.forename: Qingang
authors.initials: Q
authors.lastname: Hu
authors.forename: Guowen
authors.initials: G
authors.lastname: Sun
mesh_terms: D000328:Adult; D000564:Ameloblastoma / Q000473:pathology* / Q000556:secondary; D002277:Carcinoma / Q000473:pathology*; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D006801:Humans; D008175:Lung Neoplasms / Q000556:secondary; D008297:Male; D008441:Maxillary Neoplasms / Q000473:pathology*; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D010579:Petrous Bone / Q000473:pathology; D056739:Pterygopalatine Fossa / Q000473:pathology; D012888:Skull Neoplasms / Q000473:pathology