Odontogenic cysts: calcifying odontogenic cyst

Mandible & maxilla
Odontogenic cysts
Calcifying odontogenic cyst

Authors: Annie S. Morrison, M.D., Kelly Magliocca, D.D.S., M.P.H.

Topic Completed: 1 September 2013

Minor changes: 13 December 2019

Copyright: 2003-2019, PathologyOutlines.com, Inc.

PubMed Search: Calcifying odontogenic cyst AND free full text[sb] AND Humans[Mesh]

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Table of Contents

Cite this page: Morrison, A. Odontogenic cysts: calcifying odontogenic cyst. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/mandiblemaxillacalcifyingodontogenic.html. Accessed May 27th, 2020.

Definition / general

WHO defines entity as a benign cystic neoplasm of odontogenic origin, characterized by an ameloblastoma-like epithelium with ghost cells that may calcify
Originally described by Gorlin and colleagues in 1962 as a possible oral analogue to pilomatrixoma of skin, owing to the presence of ghost cell keratinization in both lesions

Terminology

Calcifying cystic odontogenic tumor (CCOT) is preferred 2005 WHO terminology
However, also called Gorlin cyst, calcifying odontogenic cyst (COC) , keratinizing and calcifying odontogenic cyst

Commonly used terminologies
Peripheral COC: in gingival tissues, ie: extra-osseous
Central COC: within bone of jaws, ie: intra-osseous.
The following discussion pertains only to central COC
Several histopathologic classifications have been delineated, with nearly a dozen potential subgroupings
From a practical standpoint, a spectrum of histopathologic patterns exists, ranging from a benign lesion that is primarily cystic, a benign lesion with a solid pattern of growth to a rare tumor with features of carcinoma
Solid lesions may be more aptly designated Dentinogenic Ghost cell tumors
Simple cystic, non-proliferative: single chambered cyst lined by squamous or stellate reticulumlike cells with a degree of palisading of the basal cells; ghost cells present, eosinophilic dentinoid is variably present and often juxtaepithelial, but no other hard tissues seen
Cystic, proliferative/ameloblastomatous: in addition to simple cystic features, there is proliferation of ameloblastoma-like cords, islands, and sheets of epithelium with palisading of basal cell nuclei with reverse polarization within the wall; odontogenic epithelial proliferations that can superficially resemble ameloblastoma extend into the lumen as well as the connective tissue wall of the lesion
Odontoma-associated: Odontoma-like tissues are seen in the wall of the lesion; when associated with an odontoma, patient age tends to be younger, with mean age 17 years
Dentinogenic ghost cell tumor:
- Also called epithelial odontogenic ghost cell tumor, odontogenic ghost cell tumor
- Similar components to COC, but without a cystic structure and with a neoplastic growth pattern (Odontogenic ghost cell tumor)
- For a detailed classification of ghost cell tumors, refer to Table 2 of the International collaborative study on ghost cell odontogenic tumours (J Oral Pathol Med 2008;37:302)
See also Am J Surg Pathol 2003;27:372, Oral Surg Oral Med Oral Pathol 1991;72:56

Epidemiology

6% of central odontogenic tumors (J Oral Maxillofac Surg 2006;64:1343)
Mean age 31 years, range 5 - 92 years
No consistent gender predominance (studies report both)
85% have cystic component, 15% have solid pattern reminiscent of neoplastic process

Sites

Usually anterior regions of jaws, incisor cuspid region

Pathophysiology

Controversial whether a developmental cyst or a true neoplasm
In 1992, WHO classified this lesion as odontogenic tumor but continued to use the term calcifying odontogenic cyst
In 2005, WHO redesignated the lesion as calcifying cystic odontogenic tumor
Although the condition is often described as being cystic (> 85% of the cases), a significant percentage of calcifying odontogenic cysts grow as more solid, seemingly neoplastic proliferations, and the term dentinogenic ghost cell tumor has been used to describe these lesions
Even the cystic lesion has apparent neoplastic potential but most appear to be non-neoplastic

Clinical features

Either none (incidental radiographic finding of painless bony expansile remodeling) or pain
May be associated with other odontogenic pathology, most commonly odontoma

Radiology description

Usually unicystic, well defined radiolucency with focal opacification (Br J Radiol 2012;85:548) but 10 - 25% are multilocular
Scattered radiopacities in 1/3 to 1/2
1/3 associated with impacted tooth
Usually 2 - 4 cm, but up to 12 cm
Adjacent tooth root resorption or root divergence may occur (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:356)

Prognostic factors

Prognosis excellent, few recurrences (< 5%) documented
Rarely malignant transformation (Case Rep Pathol 2013;2013:853095, Korean J Pathol 2012;46:478, Ann Diagn Pathol 2009;13:394)

Case reports

15 year old Japanese boy with pigmented calcifying cystic odontogenic tumor associated with compound odontoma (Head Face Med 2007;3:35)
23 year old man with ameloblastic fibro-odontoma arising from a calcifying odontogenic cyst (Bull Tokyo Dent Coll 2001;42:51)
24 year old woman with calcifying odontogenic cyst associated with an orthokeratinized odontogenic cyst (Head Neck Pathol 2008;2:324)
Calcifying odontogenic cyst with odontogenic keratocyst (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:e40)
Hybrid odontogenic tumor with features of ameloblastic fibro-odontoma, calcifying odontogenic cyst, and adenomatoid odontogenic tumor (J Oral Maxillofac Surg 2010;68:470)
Calcifying odontogenic cyst with ameloblastic fibroma (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2004;98:451)

Treatment

Treated by enucleation and curettage
For combined lesions, treat according to characteristics of more aggressive lesion

Clinical images

Images hosted on other servers:

Calcifying odontogenic cyst causing swelling

Edentulous arch with swelling in the 14 and 15 region

Appearance of swelling

Palatally swelling

Swelling obliterating buccal vestibule

Gross description

Unicystic, often 2 cm or less; no solid areas

Microscopic (histologic) description

Well defined layer of palisading basal cells, loosely arranged suprabasal epithelial cells resembling stellate reticulum similar to ameloblastoma
Unlike ameloblastoma, variable numbers of lesional epithelial cells undergo ghost cell change in suprabasilar epithelium
Epithelium also contains pale, eosinophilic ghost cells that may keratinize or calcify; dentin may be laid down next to basal cells; variable foreign body reaction
Ghost cells: altered epithelial cells with preservation of basic cell outline, eosinophilic cytoplasm, but loss of nucleus
Can exhibit dystrophic calcifications
Ghost cell change may be due to coagulative necrosis, accumulation of enamel protein, aberrant keratinization of odontogenic epithelium
Dentinoid:
- Varying amounts of a paucicellular, eosinophilic calcified material considered to represent dysplastic dentin
- May be present adjacent to epithelial component
- Probably due to inductive effect by odontogenic epithelium on adjacent mesenchymal tissue

Microscopic (histologic) images

Images hosted on PathOut server:

Contributed by Kelly R. Magliocca, D.D.S., M.P.H.

Calcifying odontogenic cyst, 3x

Epithelium with calcifications and ghost cells, 10x

Calcifying odontogenic cyst epithelium with ghost cells, 20x

Calcifying odontogenic cyst, scanning magnification

Images hosted on other servers:

Ameloblastic epithelium, calcifications and ghost cells

Ameloblastic islands

Ghost cells with preservation of basic cellular outline

Ghost cells undergoing calcifications

Cytology description

Numerous polyhedral epithelial cells and occasional columnar cells with calcification and Congo red-negative extracellular homogenous material in background (Acta Cytol 2009;53:460)

Positive stains

Cytokeratins 7, 8, 14 and 19 (J Oral Pathol Med 2003;32:163)
Beta-catenin (APMIS 2008;116:206, Pathol Int 2006;56:732, Am J Clin Pathol 2003;120:732, Am J Pathol 2003;163:1707)
Amelogenesis related proteins (J Oral Pathol Med 2012;41:272)
MMPs: Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011;112:609
Hard alpha-keratins (Am J Clin Pathol 2005;123:376)
Podoplanin (J Oral Sci 2012;54:165)

Negative stains

Ki67 lower in COC than in other odontogenic tumors with ghost cells and solid growth pattern (Oral Oncol 2009;45:515)

Electron microscopy description

Basal and suprabasilar cells contain tonofilaments and organelles
Ghost cells contain coarse bundles of tonofilaments intermingled with dilated membranous organelles (Med Electron Microsc 2002;35:109, Oral Surg Oral Med Oral Pathol 1975;39:769)

Molecular / cytogenetics description

Aberrations of Wnt signaling pathway with beta-catenin overexpression (APMIS 2008;116:206)

Differential diagnosis

Central jaw lesion with basal palisading of epithelium
- COC
- COC in combination with second tumor
- Ameloblastoma
- Keratocystic odontogenic tumor
- Dentinogenic ghost cell tumor/carcinoma
- Odontogenic cyst or tumor, NOS
Ghost cells identified, unknown anatomic location:
- COC
- Dentinogenic ghost cell tumor
- Ghost cell odontogenic carcinoma: infiltrative and exhibits mitotic activity, nuclear atypia, and/or necrosis.
- Odontoma
- Ameloblastic fibro-odontoma
- Pilomatrixoma
- Matrical carcinoma
- Craniopharyngioma