Papilliferous Keratoameloblastoma (PKA): Is It a Different Clinicopathological Entity or Histological Subtype of Conventional Ameloblastoma?

BACKGROUND

Papilliferous keratoameloblastoma (PKA) is an exceptionally rare variant of conventional ameloblastoma, marked by papilliferous epithelial projections and prominent keratinization within an ameloblastomatous framework. Because of its rarity and overlap with other keratinizing odontogenic tumours, PKA is often overlooked and is not recognised in the current WHO classification. Limited awareness and inconsistent terminology contribute to diagnostic uncertainty and may affect clinical management.

OBJECTIVES

This review critically analysed all published PKA cases to describe their clinical, radiographic and histopathological features, evaluating whether PKA should be regarded as a distinct clinicopathological entity or a histological subtype of conventional ameloblastoma.

MATERIALS AND

METHODS

A comprehensive search of PubMed, Scopus, Web of Science, and Google Scholar was performed to identify all English-language reports of PKA. Extracted data included demographics, clinical presentation, radiographic findings, histopathology, treatment and outcomes. The information was synthesised and descriptively analysed.

RESULTS

Seven cases of PKA were included. Patients ranged from 18 to 76 years (mean age: 50.4 years), with a male predominance. All lesions involved the right mandible. Clinically, most patients presented with slow-growing mandibular swellings, occasionally accompanied by pain or mucosal changes. Radiographs most often show multilocular radiolucencies with buccolingual expansion or cortical perforation. Histopathology consistently reveals classic ameloblastomatous epithelium with squamous metaplasia, keratin pearl formation, and distinctive papilliferous projections lining cystic spaces.

CONCLUSION

The uniform histopathological pattern observed across reported cases supports recognising PKA as a distinct histopathological subtype of conventional ameloblastoma. Its formal inclusion in odontogenic tumour classification appears justified, although further molecular and clinicopathological studies are needed to better define its biological behaviour.