Keratocystic odontogenic tumour

From Libre Pathology
Jump to: navigation, search
Keratocystic odontogenic tumour
Diagnosis in short

Keratocystic odontogenic tumour. H&E stain.

Synonyms odontogenic keratocyst (old term)

LM stratified epithelium with "ribbon-like appearance" with palisaded basal cell layer, parakeratosis, artefactual separation of epithelium from the basement membrane
LM DDx odontogenic cyst (dentigerous cyst), squamous cell carcinoma
Site usually mandible - see odontogenic tumours and cysts

Syndromes nevoid basal cell carcinoma syndrome

Signs mass lesion
Prevalence uncommon
Clin. DDx ameloblastoma
Keratocystic odontogenic tumour
External resources
EHVSC 10179 10178
Wikipedia keratocystic odontogenic tumour
Pathology Outlines topic/mandiblemaxillakeratocyst
Rosai Collection 14023

Keratocystic odontogenic tumour, abbreviated KOT, is an uncommon odontogenic tumour.

It was previously known as odontogenic keratocyst, abbreviated OKC.[1]

General

Clinical

Features:[4]

  • Most common presentation: swelling.

Gross

  • Location: usually mandible.
  • May mimic ameloblastoma radiologically.

Microscopic

Features: [5]

  • Stratified epithelium (resembling squamous epithelium) with:
    • "Ribbon-like appearance" - important.
      • Typically 8-10 cell layers thick - with relatively uniform thickness.
      • Lacks rete ridges.
    • Palisaded basal cell layer.
  • Parakeratosis (keratinized cells with nuclei) - key feature.
  • Artefactual separation of epithelium from the basement membrane.

DDx:

Images

www:

See also

References

  1. Madras, J.; Lapointe, H. (Mar 2008). "Keratocystic odontogenic tumour: reclassification of the odontogenic keratocyst from cyst to tumour.". J Can Dent Assoc 74 (2): 165-165h. PMID 18353202.
  2. Lee, JW.; Gates, R.; Wignall, A. (Aug 2011). "Squamous cell carcinoma arising from a keratocystic odontogenic tumor.". Otolaryngol Head Neck Surg 145 (2): 356-7. doi:10.1177/0194599811399270. PMID 21493332.
  3. Tan, B.; Yan, TS.; Shermin, L.; Teck, KC.; Yoke, PC.; Goh, C.; Balakrishnan, A.. "Malignant transformation of keratocystic odontogenic tumor: Two case reports.". Am J Otolaryngol 34 (4): 357-61. doi:10.1016/j.amjoto.2013.01.002. PMID 23374486.
  4. Habibi, A.; Saghravanian, N.; Habibi, M.; Mellati, E.; Habibi, M. (Sep 2007). "Keratocystic odontogenic tumor: a 10-year retrospective study of 83 cases in an Iranian population.". J Oral Sci 49 (3): 229-35. PMID 17928730.
  5. Thompson LDR. Head and neck pathology - (Foundations in diagnostic pathology). Goldblum JR, Ed.. Churchill Livingstone. 2006. ISBN 0-443-06960-3.
  6. Macdonald-Jankowski, DS. (Dec 2010). "Orthokeratinized odontogenic cyst: a systematic review.". Dentomaxillofac Radiol 39 (8): 455-67. doi:10.1259/dmfr/19728573.
  7. URL: http://www.sciencedirect.com/science/article/pii/S0968605305000992#fig5. Accessed on: 11 March 2013.