Keratocystic odontogenic tumours- which surgical approach?


The keratocystic odontogenic tumour (KOT) which was previous known as the odontogenic keratocyst is a benign but locally aggressive tumour known for its high recurrence rate. A wide range of treatment options have been reported including enucleation alone, enucleation with curettage, enucleation with adjunctive therapy (Carnoy’s solution, cryotherapy, and peripheral ostectomy), marsupialisation or decompression with or without secondary cystectomy and adjunctive therapy, and resection.

The aim of this review was to identify the best surgical treatment with the lowest recurrence rate for keratocystic odontogenic tumours (KOTs)


Searches were conducted in the PubMed, Ovid MEDLINE, Cochrane CENTRAL and Google Scholar databases. Prospective randomised controlled clinical trials (RCTs) , controlled clinical studies (CCS), either prospective or retrospective, and case series on patients having surgical treatment for KOT (primary or recurrence) with at least 1 year follow up were considered.

Two reviewers independently screened studies, abstracted data and assessed risk of bias using the Newcastle-Ottawa Scale. The recurrence rate of KOTs was pooled and reported as event rates with corresponding 95% confidence intervals.


  • 35 studies were included.
  • There were no randomised controlled trials
  •  The overall weighted pooled recurrence rate of all included studies was 16.6% (95%CI; 12.3%-22%).
  • Weighted pooled recurrence rate for difference surgical approaches are shown in the table below
Treatment No. of studies No of KOTs Recurrence rate (95%CI)
Enucleation alone 17 891 23.1% (17.3% – 30.2%)
Enucleation with curettage 8 378 17.4% (11.2% – 26.1%)
Enucleation and Carnoy’s solution 16 549 11.5% (6.8% – 18.8%)
Enucleation plus liquid nitrogen cryotherapy 6 173 14.5% (5.1% – 34.9%)
Marsupialization alone 8 63 32.3% (16.9% – 52.8%)
Decompression followed by residual cystectomy 9 141 14.6% (9.2% – 22.3%)
Resection 7 92 8.4% (3.5% – 18.8%)


The authors concluded

radical resection remains the sure option for obtaining the lowest recurrence with KOTs. We believe that in an attempt to achieve the least possible morbidity, resections should be reserved for multiple recurrent lesions and possibly syndromic cases. However, to achieve the least recurrence, enucleation with application of Carnoy’s solution or cryotherapy is the first-line treatment for primary KOTs. Additionally, marsupialisation (where indicated) must be followed by secondary cystectomy to minimize recurrence.


A number of systematic reviews of treatments for KOT have been conducted since 2000 (Dental Elf – 2nd Jul 2014) including a Cochrane review (Dental Elf – 10th Nov 2015). However, all the reviews are hampered to a greater of lesser extent by the fact that no randomised controlled trials have been conducted to compare one treatment approach against another. This latest review has conducted a fairly extensive search of a number of databases and included 35 studies meeting their criteria finding that the overall pooled recurrence rate was 16.6% (95%CI; 12.3 – 22).  This compares to an estimated probability of recurrence of 21.1% (95%CI; 18.4-  23.7) estimated by Chrcanovic et al in another recent review and comparisons with other approach between the two reviews are shown in the table below.

Treatment Al-Moraissi et al

Recurrence rate (95%CI)

Chrcanovic et al

Probability of recurrence (95%CI)

Enucleation with curettage 17.4% (11.2% – 26.1) 22.5% (19.1 – 26.0)
Enucleation and Carnoy’s solution 11.5% (6.8 – 18.8) 5.3% (2.9 – 7.7)
Enucleation plus liquid nitrogen cryotherapy 14.5% (5.1 – 34.9) 20.9% (8.4 – 33.3)
Marsupialization alone 32.3% (16.9 – 52.8) 28.7% (17.7 – 39.8)
Resection 8.4% (3.5 – 18.8) 2.2% (0.2 – 4.3)


 A majority of the included studies (27)  in this review were retrospective so the underlying quality of the primary studies in this and the Chrcanovic et al  review mean that these estimates should be interpreted with caution. High quality prospective studies are needed to clarify the most effective treatment and the recurrence rates for this troublesome tumour.


Primary paper

 Al-Moraissi EA, Dahan AA, Alwadeai MS, Oginni FO, Al-Jamali JM, Alkhutari AS, Al-Tairi NH, Almaweri AA, Al-Sanabani JS. What surgical treatment has the lowest recurrence rate following the management of keratocystic odontogenic tumor?: A large systematic review and meta-analysis. J Craniomaxillofac Surg. 2017Jan;45(1):131-144. doi: 10.1016/j.jcms.2016.10.013. PubMed PMID: 27955959.

Other references

Chrcanovic BR, Gomez RS. Recurrence probability for keratocystic odontogenic tumors: An analysis of 6427 cases. J Craniomaxillofac Surg. 2016 Nov 19. pii: S1010-5182(16)30285-2. doi: 10.1016/j.jcms.2016.11.010. [Epub ahead of print] PubMed PMID: 28011178.


Dental Elf – 10th Nov 2015

No high quality evidence of treatments for keratocyst


Dental Elf – 2nd Jul 2014

Another review finds limited evidence for making treatment recommendations for keratocystic odontogenic tumors

Share on Facebook Tweet this on Twitter Share on LinkedIn Share on Google+