Mandible / maxilla
Odontogenic cysts
Calcifying odontogenic cyst

Author: Annie S. Morrison, M.D.
Senior Author: Kelly R. Magliocca, D.D.S., M.P.H.

Revised: 4 October 2018, last major update September 2013

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

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

Cite this page: Morrison, A. Odontogenic cysts: calcifying odontogenic cyst. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/mandiblemaxillacalcifyingodontogenic.html. Accessed November 12th, 2018.
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
Prognostic factors
Case reports
Treatment
  • Treated by enucleation and curettage
  • For combined lesions, treat according to characteristics of more aggressive lesion
Clinical images

Images hosted on other servers:
Missing Image

Calcifying odontogenic cyst causing swelling

Missing Image

Edentulous arch with swelling in the 14 and 15 region

Missing Image

Appearance of swelling

Missing Image

Palatally swelling

Missing Image

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.
Missing Image

Calcifying odontogenic cyst, 3x

Missing Image

Epithelium with calcifications and ghost cells, 10x

Missing Image

Calcifying odontogenic cyst epithelium with ghost cells, 20x

Missing Image

Calcifying odontogenic cyst, scanning magnification



Images hosted on other servers:
Missing Image

Ameloblastic epithelium, calcifications and ghost cells

Missing Image

Ameloblastic islands

Missing Image

Ghost cells with preservation of basic cellular outline

Missing Image

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)
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
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