Primordial odontogenic tumour: clinicopathological analysis of six cases of a previously undescribed entity.
AIM
To describe the clinicopathological and immuno-histochemical features of six tumours that do not fulfil the criteria of any of the currently classified odontogenic tumours.


METHODS AND RESULTS
The patients were three males and three females, whose ages ranged from 3 years to 18 years (mean, 11.05 years). In all cases there were well-defined radiolucencies associated with unerupted teeth apparently showing a pericoronal relationship. Microscopically, all tumours were composed of variably cellular loose fibrous tissue with areas similar to dental papilla, entirely surrounded by cuboidal to columnar epithelium resembling the internal epithelium of the enamel organ. Mesenchymal tissue was positive only for vimentin, and Ki67 expression was very low (<2%). The epithelium was positive for CK AE1/AE3, CK5, CK14, and CK19, but negative for CK18 and CK20. All cases showed clear demarcation from the surrounding bone, and were surgically removed, with no recurrences after follow-up ranging from 6 months to 20 years.


CONCLUSIONS
These findings differ from those observed in other odontogenic lesions, such as ameloblastic fibroma, odontogenic myxoma, odontogenic fibroma, and hyperplastic dental follicles. The term primordial odontogenic tumour is proposed to describe this novel lesion.
['Mosqueda-Taylor|Adalberto|A|', 'Pires|Fabio Ramoa|FR|', 'Aguirre-Urízar|José Manuel|JM|', 'Carlos-Bregni|Roman|R|', 'de la Piedra-Garza|José Mario|JM|', 'Martínez-Conde|Rafael|R|', 'Martínez-Mata|Guillermo|G|', 'Carreño-Álvarez|Sergio J|SJ|', 'da Silveira|Henrique Martins|HM|', 'de Barros Dias|Bruno Santos|BS|', 'de Almeida|Oslei Paes|OP|']
D000293:Adolescent D014408:Biomarkers, Tumor D004848:Epithelium D005260:Female D006801:Humans D007150:Immunohistochemistry D007573:Jaw Neoplasms D008297:Male D009808:Odontogenic Tumors
odontogenic tumour dental papilla dental follicle jaws tooth primordium