Keratocystic Odontogenic Tumor Recurrence Research Articles

A review on the most important management of keratocystic odontogenic tumor.

Keratocystic odontogenic tumor (KCOT) is a recurrent benign tumor with a keratinized epithelial shape. The treatment methods in KCOT are still debated. The aim of all treatment methods is to eradicate the cyst and to reduce recurrence and surgical complications. This review article was conducted to assess the findings of studies on the dia-gnosis, management and recurrence of KCOT. Information were gathered by searching keywords such as management, treatment, pharmacology, surgery and keratocystic odontogenic tumor in international databases such as Web of Science, PubMed and Scopus. The search period was between 2010-2020. Techniques used for the treatment include decompression, marsupialization, enucleation with or without adjunct, Caldwell-Luc surgery and resection. Of the 40 studies, recurrence was observed in 13 studies and the recurrence ranged from 0 to 48% in different treatment methods. Due to the high recurrence of this disease, it is suggested that long term follow-up be considered after treatment to reduce recurrence. Decision on the treatment should be made considering age, tumor size, and the site of involvement in order to reduce the economic and psychological burden of the disease.

The Use of Carnoy’s Solution and Its Modifications for Reducing the Number of Recurrences after Surgical Removal of Keratocystic Odontogenic Tumors and Ameloblastomas: A Systematic Review

The paper is a systematic review of using the pharmaceutical substance, Carnoy’s solution, to reduce the number of recurrences of such tumors as keratocystic odontogenic tumor and ameloblastoma. These are benign yet aggressive jaw tumors with a high percentage of recurrences (up to 60–80%). Surgical treatment of the above-described lesions can be performed using: (1) marsupialization (recurrence rate up to 24.8%); (2) enucleation with or without adjunct therapy; therapy may include cryotherapy with liquid nitrogen (recurrence rate up to 23.1%), peripheral ostectomy (recurrence rate up to 20%), and bone cavity treatment with Carnoy’s solution (recurrence rate up to 6.6%); (3) marginal/segmental resection of the jaw (recurrence rate up to 2.5%). Despite the low percentage of recurrences when using marginal/segmental resection, this method requires a longer and more expensive anesthetic and surgical intervention as well as longer postoperative and rehabilitation periods. With the use of Carnoy’s solution, it became possible to reduce the risks of recurrence of keratocystic odontogenic tumors and ameloblastomas from 60–80 to 6.6‒11.5%. Worldwide today, not only Carnoy’s solution recommended by Cutler and Zollinger in 1933 is applied but also its modifications that are not inferior to the original substance in terms of removal efficiency of the remaining cystic cells. The safety of the use of the solution near the vessels and nerves is confirmed by works of a number of authors. It is concluded that, despite the large number of surgical treatments of both keratocystic odontogenic tumors and ameloblastomas, enucleation with the use of Carnoy’s solution is the optimal method of choice for these diseases.

Histopathological and immunohistochemical study in keratocystic odontogenic tumors: Predictive factors of recurrence.

The aim of the present study was to identify the most useful markers for predicting recurrence of keratocystic odontogenic tumors (KCOTs). A total of 65 tumor samples from 63 patients diagnosed with typical parakeratinized cysts and KCOTs between 1992 and 2014 were retrospectively studied. Clinical and histopathological data and treatment modality were reviewed. In addition, the expression profiles of Ki-67, cluster of differentiation (CD)34 and podoplanin were assessed using immunohistochemistry. The association between these factors and the rate of KCOT recurrence was evaluated. The presence of daughter cysts, epithelial islands and high Ki-67, CD34 and podoplanin expression levels were revealed to be associated with tumor recurrence. In particular, univariate analysis revealed that high CD34 expression levels were significantly associated with tumor recurrence (P=0.034), as was conservative surgical treatment (P=0.003). Multivariate analysis revealed that conservative treatment was the greatest independent risk factor for tumor recurrence (odds ratio=13.337; P=0.018). These results suggest that overexpression of CD34 may be a potent predictor of tumor recurrence and radical treatment of the teeth that are in contact with the tumors is recommended in order to prevent tumor recurrence.

Recurrence probability for keratocystic odontogenic tumors: An analysis of 6427 cases.

To investigate and compare the probability of recurrence of keratocystic odontogenic tumors (KCOTs) for different variables and treatment protocols. An electronic search was undertaken in April 2016 that included clinical series of KCOTs reporting recurrences. Untransformed proportions and meta-analyses were performed to estimate the probability/risk of recurrence, according to several variables. A total of 94 publications were included (6427 KCOTs, 1464 recurrences). Probability of recurrence: all lesions, 21.1%; nevoid basal cell carcinoma syndrome, 35.4%; males, 20.3%; females, 19.3%; maxilla, 15.3%; mandible, 21.5%; unilocular, 14.7%; multilocular, 24.4%; marsupialization/decompression, 28.7%; decompression+enucleation±additional therapy, 18.6%; enucleation/curettage, 22.5%; enucleation+peripheral ostectomy, 18.6%; enucleation+Carnoy's solution, 5.3%; enucleation+cryotherapy, 20.9%; marginal/segmental resection, 2.2%. The recurrence was not statistically significantly affected by lesion location (maxilla vs. mandible, risk ratio [RR] 0.92, P=0.32) or patient's sex (male vs. female, RR 0.94, P=0.44), but by locularity (unilocular vs. multilocular, RR 0.67, P=0.007). Recurrence risk for surgical managements: marsupialization vs. enucleation (RR 1.65, P=0.0006), marsupialization vs. resection (RR 3.17, P=0.009), enucleation alone vs. enucleation+peripheral ostectomy (RR 1.66, P=0.05), enucleation alone vs. enucleation+Carnoy's solution (RR 1.94, P=0.03), enucleation alone vs. enucleation+cryotherapy (RR 0.88, P=0.56). KCOTs have a considerable rate of recurrence, which varies significantly according to some clinical, radiographic, and histopathological features, as well as surgical management.

Trends in Recurrence of Keratocystic Odontogenic Tumor

Trends in Recurrence of Keratocystic Odontogenic Tumor

Keratocystic Odontogenic Tumor Recurrence Rates With Enucleation and Curettage Using Carnoy's Versus Modified Carnoy's Solution

Keratocystic Odontogenic Tumor Recurrence Rates With Enucleation and Curettage Using Carnoy's Versus Modified Carnoy's Solution

Management and recurrence of keratocystic odontogenic tumor: a systematic review

The objective of this study was to evaluate the most up-to-date treatment modalities and respective recurrence rates for keratocystic odontogenic tumor (KCOT). A systematic review of the literature from 1999 to 2010 was undertaken examining treatment and recurrence rates for KCOT. Four inclusion criteria were defined for articles to then be analyzed against 8 standards. Of the 2736 published articles, 8 met the inclusion criteria. When merging the data, enucleation and enucleation with adjunctive measures (other than Carnoy's solution) had recurrence rates of 25.6% and 30.3%, respectively. Marsupialization with adjunctive measures produced a recurrence rate of 15.8%, whereas enucleation with Carnoy's solution presented a recurrence rate of 7.9%. Only one resection case had recurrence (6.3%). The enucleation technique with the use of adjunctive procedures (other than Carnoy's solution) provides a higher recurrence rate than any other treatment modality.

A clinical study on the recurrence of keratocystic odontogenic tumor

角化嚢胞性歯原性腫瘍は，歯原性上皮に由来する単房性もしくは多房性の顎骨内腫瘍で，錯角化を呈する重層扁平上皮により裏装されている。多発性の本腫瘍は母斑基底細胞癌症候群の徴候の一つとして知られている。本腫瘍の臨床的な特徴としては，周囲組織に対して侵襲的な態度を示すことや，再発傾向があることなどがある。今回われわれは，2001年から2010年までの10年間に東京医科歯科大学歯学部附属病院顎口腔外科で加療した角化嚢胞性歯原性腫瘍68例（男性39例，女性29例），90腫瘍について臨床的に検討した。このうち8例（男性3例，女性5例），30腫瘍は母斑基底細胞癌症候群例であった。全90腫瘍のうち24腫瘍で再発を認め，再発率は26.7%であった。開窓・摘出術を行った腫瘍の再発率（16.1%）は，開窓療法を行わず摘出術を行った腫瘍の再発率（34.5%）より低かった。腫瘍に接する歯を根治的に処置した腫瘍の再発率（3.4%）は，保存的に処置した腫瘍の再発率（37.7%）より低かった。再発は，その多くが保存した歯の歯根付近から生じていた。これは，この部位は腫瘍の摘出が困難なため，不完全になってしまうことによると考えられた。腫瘍の摘出から再発までの期間は6か月から5年に分布し，ほとんどが3年以内であった。よって，腫瘍摘出後は最低3年間は定期的に経過観察を行う必要があると考えられた。

Clinicopathological and immunohistochenical examination on the recurrence of keratocystic odontogenic tumor

Clinicopathological and immunohistochenical examination on the recurrence of keratocystic odontogenic tumor

Computerized tomography findings and recurrence of keratocystic odontogenic tumor of the mandible and maxillofacial region in a series of 46 patients

The aim of this study was to evaluate the computerized tomography (CT) features of keratocystic odontogenic tumors (KCOTs). Another aim was to determine the recurrence rate of KCOTs during a mean follow-up of 4.7 years. The CT features of histopathologically verified KCOTs in 46 patients were reviewed. The features examined included the shape of the lesion, the lesion's influence on surrounding structures, such as cortical bone and teeth, and the behavior of contrast medium. The recurrence rate and the time to recurrence were determined in the series. In the body of the mandible, KCOTs demonstrated only minimal cortical expansion. The vast majority of the lesions caused border scalloping in both jaws. In the maxilla, this could be demonstrated only by CT. Increased attenuation within the tumor cavity that did not show enhancement was evident in 30% of cases. Recurrences occurred in 39% of the patients, with a mean time to a recurrence of 2.2 years. The CT features that should arouse suspicion of a KCOT include high attenuation areas in the inner part of the lesion, minimal expansion in the body of the mandible, and border scalloping. The high recurrence rate of KCOT makes periodic and long-term follow-up important. The importance of CT imaging in the follow-up is stressed, especially in the maxilla because of its complex 3-dimensional anatomy.

Prognostic factors for keratocystic odontogenic tumor (odontogenic keratocyst): analysis of clinico‐pathologic and immunohistochemical findings in cysts treated by enucleation

The purpose of this study was to determine prognostic factors for the recurrence of keratocystic odontogenic tumors (KCOTs) following simple enucleation by examining clinico-pathologic and immunohistochemical findings. Following enucleation, the frequency of recurrence among 32 subjects diagnosed with KCOT was analyzed for tumor site, radiographic and histologic features, and immunopositivity for Ki-67 and p53. Keratocystic odontogenic tumors in four out of 32 subjects (12.5%) recurred during the follow-up period (median: 33 months, range: 7-114 months). Three out of four subjects (75.0%) among recurrent group showed high expression of Ki-67 (LI >10%) in basal layer and four (4/28; 14.3%) among non-recurrence group (P = 0.025). Expression of p53 among non-recurrent group was observed in 11 subjects (11/28; 39.3%), and in three subjects (3/4; 75.0%) among the recurrent group (P = 0.295). Hazard risk for the recurrence of KCOT was 4.02 (95% CI 1.42-18.14) for high Ki-67 expression in the basal layer by the Cox proportional hazard model (P = 0.009). In our study, none of the other clinico-pathologic variables were associated with the recurrence of KCOT. The results suggested that the evaluation of Ki-67 expression in KCOT at the time of pathological diagnosis might be helpful for consideration of appropriate adjunctive surgical procedures to avoid a recurrence and may serve as a prognostic marker.

O.125 Recurrence of keratocystic odontogenic tumors

O.125 Recurrence of keratocystic odontogenic tumors

Recurrence of Keratocystic Odontogenic Tumor: Clinicopathological Features and Immunohistochemical Study of the Hedgehog Signaling Pathway

Aims: Critical factors responsible for the recurrence of keratocystic odontogenic tumor (KCOT) were examined. Methods: The clinicopathological features were retrospectively studied in 74 patients with 75 sporadic KCOTs. From the 75 KCOTs, 23 were examined for the expression of Sonic Hedgehog (SHH), Patched and Smoothened (SMO) by immunohistochemistry. Results: Recurrence in multilocular lesions was more frequent than in unilocular lesions. Nine (64%) of 14 multilocular lesions recurred, in contrast to 2 (7%) of 27 unilocular lesions (p = 0.0350). The average length of recurrent lesions (62.8 ± 6.5 mm) was larger than that of nonrecurrent lesions (43.0 ± 4.0 mm; p = 0.0363). The immunoreactivity of proliferation-related SMO in KCOTs with recurrence was higher than that of those without recurrence (p = 0.0475), whereas the expressions of a ligand, SHH, and an inhibitory receptor, Patched, were not associated with KCOT recurrence. The expressions of SHH and SMO showed inverse correlation in whole KCOT (p = 0.0318). Conclusion: These findings suggest that recurrence of KCOT is associated with multilocular large lesions and high SMO expression.