Odontogenic keratocyst

Odontogenic keratocyst
Other namesKeratocystic odontogenic tumour (KCOT)
Micrograph of an odontogenic keratocyst. H&E stain.

An odontogenic keratocyst is a rare and benign but locally aggressive developmental cyst. It most often affects the posterior mandible and most commonly presents in the third decade of life.[1] Odontogenic keratocysts make up around 19% of jaw cysts.[2] Despite its more common appearance in the bone region, it can affect soft tissue. [3]

In the WHO/IARC classification of head and neck pathology, this clinical entity had been known for years as the odontogenic keratocyst; it was reclassified as keratocystic odontogenic tumour (KCOT) from 2005 to 2017.[4][5] In 2017 it reverted to the earlier name, as the new WHO/IARC classification reclassified OKC back into the cystic category.[6] Under The WHO/IARC classification, Odontogenic Keratocyst underwent the reclassification as it is no longer considered a neoplasm due to a lack of quality evidence regarding this hypothesis, especially with respect to clonality. Within the Head and Neck pathology community there is still controversy surrounding the reclassification, with some pathologists still considering Odontogenic Keratocyst as a neoplasm in line with the previous classification.[7]

  1. ^ MacDonald-Jankowski DS (January 2011). "Keratocystic odontogenic tumour: systematic review". Dento Maxillo Facial Radiology. 40 (1): 1–23. doi:10.1259/dmfr/29949053. PMC 3611466. PMID 21159911.
  2. ^ Crispian S (2008). Oral and maxillofacial medicine : the basis of diagnosis and treatment (2nd ed.). Edinburgh: Churchill Livingstone. ISBN 9780443068188. OCLC 123962943.
  3. ^ Stoelinga, P, et al. (January 2022). "The extra-osseous odontogenic keratocyst: An anachronism?". Journal of Stomatology Oral and Maxillofacial Surgery. 123 (6): e790–e793. doi:10.1016/j.jormas.2022.07.001. PMID 35798194.
  4. ^ Barnes L, Eveson JW, Reichart P, Sidransky D, eds. (2005). World Health Organization Classification of Tumours: Pathology and Genetics of Head and Neck Tumours (PDF) (2005 ed.). Lyon, France: IARC Press. ISBN 978-92-832-2417-4. Archived from the original (PDF) on 2015-09-24.
  5. ^ Madras J, Lapointe H (March 2008). "Keratocystic odontogenic tumour: reclassification of the odontogenic keratocyst from cyst to tumour". Journal. 74 (2): 165–165h. PMID 18353202.
  6. ^ El-Naggar AK, Chan JK, Grandis JR, Takata T, Slootweg PJ, eds. (2017). WHO Classification of Head and Neck Tumours. WHO/IARC Classification of Tumours. Vol. 9 (4th ed.). Lyon, France: IARC Press. ISBN 978-92-832-2438-9.
  7. ^ Wright JM, Vered M (March 2017). "Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Odontogenic and Maxillofacial Bone Tumors". Head and Neck Pathology. 11 (1): 68–77. doi:10.1007/s12105-017-0794-1. PMC 5340735. PMID 28247226.