title: Ameloblastic carcinoma (secondary type) with extensive squamous differentiation areas and dedifferentiated regions.
abstract: Ameloblastic carcinoma is rare, accounting for 1.5%-2.0% of all odontogenic tumors. Few small series are available, but data on its clinicopathologic characteristics derive mainly from single case reports; therefore, descriptions of new cases may help to better understand the biological characteristics of this rare odontogenic malignancy. In the current report we describe an ameloblastic carcinoma affecting a 27-year-old female patient who had a previous diagnosis of ameloblastoma 7 years before. The carcinoma featured extensive areas of squamous differentiation resembling a primary intraosseous squamous cell carcinoma, as well as areas of dedifferentiation, a poorly documented histologic characteristic of ameloblastic carcinoma. This case provides new insights on the microscopic spectrum of ameloblastic carcinoma, permitting a critical discussion of the current World Health Organization classification of this odontogenic tumor.
authors.affiliation: Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil.
authors.forename: Felipe Paiva
authors.initials: FP
authors.lastname: Fonseca
authors.affiliation: Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil.
authors.forename: Oslei Paes
authors.initials: OP
authors.lastname: de Almeida
authors.affiliation: Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil.
authors.forename: Pablo Agustin
authors.initials: PA
authors.lastname: Vargas
authors.affiliation: João de Barros Barreto University Hospital, Federal University of Pará, Belém, Brazil.
authors.forename: Fábio
authors.initials: F
authors.lastname: Gonçalves
authors.affiliation: João de Barros Barreto University Hospital, Federal University of Pará, Belém, Brazil.
authors.forename: Flávia Sirotheau
authors.initials: FS
authors.lastname: Corrêa Pontes
authors.affiliation: João de Barros Barreto University Hospital, Federal University of Pará, Belém, Brazil. Electronic address: Harp@ufpa.br.
authors.forename: Hélder Antônio
authors.initials: HA
authors.lastname: Rebelo Pontes
mesh_terms: D000564:Ameloblastoma / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008339:Mandibular Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D060787:Neoplasm Grading; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor