Keratinizing odontogenic cysts with a spectrum of verrucoid morphology: investigation of a potential role of human papillomavirus

Orthokeratinized odontogenic cyst: A large series and comprehensive literature review with emphasis on synchronous multiple occurrence and neoplastic transformation

OBJECTIVES

The objective of this study was to demonstrate the clinical, radiologic, and histologic features of orthokeratinized odontogenic cyst (OOC); determine the characteristics of multiple OOCs; and present rare but significant manifestations of OOC.

STUDY DESIGN

A clinical, radiologic, and histopathologic study of 65 primary and 2 recurrent OOC cases was performed retrospectively along with a comprehensive literature review.

RESULTS

OOCs shared similar radiologic findings with odontogenic keratocyst, yet some showed features that have not been previously described: root resorption and radiopaque foci. Histologic review revealed a unique histiocytic lining and some findings suggestive of the multipotentiality of the odontogenic epithelium. The analysis of patients with multiple OOCs demonstrated that multiple OOCs occurred synchronously with a marked predilection for young male adults. Two unusual cases were also identified: an OOC combined with a BRAF^V600E ameloblastoma and a recurrent OOC with malignant transformation.

CONCLUSIONS

This largest series presents previously unreported radiographic and histopathologic features that can be seen in OOC. Multiple OOCs have clinical characteristics distinct from those of solitary cases. The first reported OOC associated with ameloblastoma suggests the involvement of oncogenic mutations in odontogenic tumorigenesis. Although OOC shows a low recurrence rate, the possibility of malignant transformation of recurrent OOCs should be emphasized.

Orthokeratinized odontogenic cysts: a Spanish tertiary care centre study based on HPV DNA detection

Background

The role of human papillomavirus (HPV) in orthokeratinized odontogenic cysts (OOCs) has rarely been studied. The objective is to describe the clinicopathological findings in a series of OOCs from a Spanish population that were investigated in relation to the possible presence of HPV.

Methods

A clinicopathological retrospective analysis followed by a molecular analysis of 28 high- and low-risk HPV genotypes was performed in OOC samples of patients seen during the last 15-years in a Spanish tertiary care center.

Results

Of 115 odontogenic cysts with keratinization, 16 cases of OOCs were confirmed and evaluated. OOCs occurred predominantly in the mandible of males (mean age 36.06 ± 13.16 years). Swelling of the jaw followed by pain were the most common clinical symptoms, and 56.5% of the OOC cases were associated with an unerupted tooth. After a mean post-cystectomy follow-up of 3.8 years, only one recurrent case was observed, resulting in a verrucous cystic lesion that was considered premalignant after immunohistological examination. DNA extraction was successful from 14 of the 16 OOC cases. None of the primary OCCs or the single recurrent OOC were positive for HPV in the molecular analysis.

Conclusions

OOCs show a very limited potential for recurrence. Our results suggest that neither high- or low-risk HPV subtypes are likely to play a role in the etiology or neoplastic transformation of OOC, at least in the Spanish population.