The keratocystic odontogenic tumor (KCOT) is a benign but locally aggressive tumour and accounts for 2-11% of jaw cysts and can occur at any age. Historically they have been referred to as odontogenic keratocyst (OKC) and primordial cyst. A range of treatment approaches have been suggested for KCOTs but preferred option is still debatable. The aim of the present study was to define and evaluate the post-treatment recurrence of KCOT lesions in non-syndromic and syndromic patients.

Searches were conducted in Medline, LILACS, BBO, IBECS, ISI Web of Knowledge, Digital Dissertations and Cochrane Database of Systematic Reviews without limits . With additional searches conducted in Google Scholar and the journals Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology, Journal of Oral and Maxillofacial Surgery, International Journal of Oral and Maxillofacial Surgery, British Journal of Oral and Maxillofacial Surgery, and Journal of Cranio-Maxillofacial Surgery.  Study selection was carried out independently by two reviewers. Studies with KCOT diagnosed histologically at least one study arm with surgical therapy and 12 months follow up were considered. The risk of bias for studies was assessed.

• 30 studies were included, 19 related to non-syndromic patients, 11 to syndromic patients.
• Of the 19 studies related to non-syndromic patients only 5 were prospective studies with the majority (74%), reporting minimum follow-up periods of less than three years.
• The overall risk of bias for these studies was considered to be moderate/high.
• Recurrence rates for 3 treatment approaches were shown
  • Enucleation only; one study arm (n = 163) had a recurrence rate of 17.8%
  • Enucleation plus adjunctive therapy; two study arms pooled (n = 51) had a recurrence rate of 10.2%
  • Other or combination of treatment; only one study arm (n = 18) with recurrence rate of 27.8%
• Of the 11 syndromic studies 8 were case series, 3 case reports.

The authors concluded

Based on existing evidence no clinical recommendations can be made for the treatment of KCOTs in either non-syndromic or syndromic patients. Additional prospective controlled clinical studies, ideally randomized and blinded, with adequate sample size and a follow-up of at least three years are needed for both nevoid basal cell carcinoma syndrome (NBCCS) and non-NBCCS cohorts.

Comment

Another group of authors has conducted a review of this topic and found limited evidence to recommend any of the treatment options that are currently being recommended for the management of KCOT. Previously we have reported on one of the other systematic reviews (Dental Elf -28^th March 2012) and highlighted the earlier Cochrane review by Sharif et al, which focussed on randomised controlled trials,  finding none. The links section below lists a number of systematic reviews identified on a quick and dirty search on Medline. What is needed now , is not more reviews. but good high quality prospective studies of sufficient size in order to provide clearer information on how to manage this locally aggressive tumour.

Links

Antonoglou GN, Sándor GK, Koidou VP, Papageorgiou SN. Non-syndromic and syndromic keratocystic odontogenic tumors: Systematic review and meta-analysis of recurrences. J Craniomaxillofac Surg. 2014 Apr 1. pii: S1010-5182(14)00100-0. doi: 10.1016/j.jcms.2014.03.020. [Epub ahead of print] PubMed PMID: 24815763.

Dental Elf -28^th March 2012 –  keratocystic odontogenic tumour recurrence rates

Sharif FNJ, Oliver R, Sweet C, Sharif MO. Interventions for the treatment of keratocystic odontogenic tumours (KCOT, odontogenic keratocysts (OKC)). Cochrane Database of Systematic Reviews 2010, Issue 9. Art. No.: CD008464. DOI: 10.1002/14651858.CD008464.pub2.

Sansare K, Raghav M, Mupparapu M, Mundada N, Karjodkar FR, Bansal S, Desai R. Keratocystic odontogenic tumor: systematic review with analysis of 72 additional cases from Mumbai, India. Oral Surg Oral Med Oral Pathol Oral Radiol. 2013 Jan;115(1):128-39. doi: 10.1016/j.oooo.2012.10.005. Review. Erratum in: Oral Surg Oral Med Oral Pathol Oral Radiol. 2013 Jun;115(6):841-2. PubMed PMID: 23217544.

Johnson NR, Batstone MD, Savage NW. Management and recurrence of keratocystic odontogenic tumor: a systematic review. Oral Surg Oral Med Oral Pathol Oral Radiol. 2013 Oct;116(4):e271-6. doi: 10.1016/j.oooo.2011.12.028. Epub 2012 Jul 6. Review. PubMed PMID: 22771402.

Kaczmarzyk T, Mojsa I, Stypulkowska J. A systematic review of the recurrence rate for keratocystic odontogenic tumour in relation to treatment modalities. Int J Oral Maxillofac Surg. 2012 Jun;41(6):756-67. doi: 10.1016/j.ijom.2012.02.008. Epub 2012 Mar 23. Review. PubMed PMID: 22445416.

MacDonald-Jankowski DS. Keratocystic odontogenic tumour: systematic review. Dentomaxillofac Radiol. 2011 Jan;40(1):1-23. doi: 10.1259/dmfr/29949053. Review. PubMed PMID: 21159911; PubMed Central PMCID: PMC3611466.

Blanas N, Freund B, Schwartz M, Furst IM. Systematic review of the treatment and prognosis of the odontogenic keratocyst. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2000 Nov;90(5):553-8. Review. PubMed PMID: 11077375.