Clear cell variant of intraosseous calcifying epithelial odontogenic tumor: a case report and review of the literature

Thirteen Synchronous Multifocal Calcifying Epithelial Odontogenic Tumors (CEOT): Case Report and Review of the Literature

BACKGROUND

Calcifying epithelial odontogenic tumor (CEOT, Pindborg tumor) is a rare, benign, locally aggressive neoplasm of the jaws that accounts for approximately 1% of all odontogenic tumors. It was first defined by Pindborg in 1955 and has been reported approximately 350 times in the literature; 7 reported multiple (up to 4) synchronous lesions.

MATERIALS AND METHODS

We report an individual with the largest number of CEOTs reported to date and provide a literature review of multifocal CEOT cases.

RESULTS

A 30-year-old male presented to the Oral and Maxillofacial Surgery Department of the West Virginia University School of Dentistry (WVU SoD) to extract multiple impacted teeth previous to construction of a complete denture. A pantograph showed 15 impacted teeth, almost all associated with well-demarcated cyst-like radiolucencies, some with small, ill-defined radiopaque flecks. Microscopically, the lesions showed sheets and strands of polygonal epithelial cells with eosinophilic cytoplasm. Spread throughout the epithelium and connective tissue were small, spherical, amorphous, pale purplish calcifications. Each lesion was similar and consistent with a diagnosis of CEOT.

CONCLUSION

We report a patient with 13 independent CEOTs scattered throughout all quadrants. This case represents the largest number of Pindborg tumors or any other type of odontogenic tumor yet reported in a single individual.

CEOT Variants or Entities: Time for a Rethink? A Case Series with Review of the Literature

The first detailed description of calcifying epithelial odontogenic tumor (CEOT) are ascribed to Jens Pindborg, but this tumor was described some years previously. Subsequently, CEOT was included in the 1971 WHO classification of odontogenic tumors and a since then number of variants have been described, which have added confusion to the diagnostic criteria. We aimed to survey the literature on the variants of CEOT, in parallel with a review of our single institution experience of CEOTs. Cases identified were collated, including available clinical, radiological and histological information and then reviewed, taking into account changes in the understanding and classifications of odontogenic tumors since initial diagnosis. We identified 26 cases from 1975 to 2017 for which histological material was available. Of these, only 13 (50%) showed the "classic" histological appearance, whilst two cases were identified as recognized variants. In 11 cases, other diagnoses or a differential diagnosis were preferred, with no agreed diagnosis in four of these. The proliferation fraction (Ki67) in the 10 cases tested was 2.1% ± 0.18. These findings illustrate the diagnostic challenges in this group of tumors and highlight the gaps in knowledge. Techniques, such as EWSR1 gene cytogenetic analysis, may be helpful in cases with clear cells. However, in other areas of controversy, including the non-calcifying and Langerhans cell rich variants, further investigation, perhaps utilizing sequencing technologies may be needed to refine the classification. Owing to the relative rarity of these lesions it would be beneficial if future work could be pursued as an international collaboration.

A Rare Case of an Aggressive Clear Cell Variant of Calcifying Epithelial Odontogenic Tumor in the Posterior Maxilla

A clear cell variant of calcifying epithelial odontogenic tumor is a rare benign odontogenic neoplasm, accounting for 33 cases described in the literature. In this article, we report a challenging example of clear cell variant of calcifying epithelial odontogenic tumor of the posterior maxilla in a 45-year-old female patient showing locally aggressive growth and recurrence. Microscopically, islands of polyhedral cells containing abundant cytoplasm, well-developed intercellular bridges blended with clear cells were observed. The nuclei were frequently pleomorphic and permeated by hyaline calcified material. Immunohistochemistry revealed positivity for pan-cytokeratin (AE1/AE3), cytokeratins (CK-14 and CK-19), Bcl-2, p53, and p63. The Ki-67 proliferative index was ~10%. As odontogenic tumors are rare, when a significant clear cell component is observed, the differential diagnosis with other lesions of the jaws with similar morphology, including other odontogenic tumors with prominent clear cell component, clear cell odontogenic carcinomas, and metastatic tumors, is difficult.

Is Conservative Surgery the Best Approach for Peripheral Calcifying Epithelial Odontogenic Tumors?

Background:

Peripheral Calcifying Epithelial Odontogenic Tumors (CEOT) rich in clear cells are a rare entity in the oral cavity, with only 14 previous case reports in the English literature. None have discussed recommended treatment approaches for extraosseous CEOT.

Objective:

This brief descriptive review describes a treatment approach for peripheral CEOT including the clear cell variant.

Study design:

A complete review of all well-documented extraosseous case reports with an emphasis on the treatment was performed. Additionally, the present article reports a case of a 21-year-old woman with an asymptomatic swelling in the gingiva finally diagnosed as peripheral CEOT abundant in clear cells.

Results:

Twenty-four cases of peripheral CEOT were described; conservative surgery was the first treatment approach in approximately 80% of cases, with only one recurrence.

Discussion:

Clear cell finding was not associated with more aggressive behavior.

Conclusion:

Conservative surgery may be an advantageous approach for this group of peripheral lesions with or without clear cells, with a recurrence rate of approximately 4%.