Treatment options for the recurrent odontogenic keratocyst

Comparison of Five Different Treatment Approaches of Mandibular Keratocystic Odontogenic Keratocyst (OKC): A Retrospective Recurrence Analysis of Clinical and Radiographic Parameters

The odontogenic keratocyst (OKC) is a benign but locally aggressive growing lesion that infiltrates the bone and surrounding tissue. It is characterized by high rates of recurrence along with rapid growth. Different forms of partly successful treatment therapies are reported. The retrospective study at hand examined 114 patients with OKC treated over a period of 20 years. Data extracted includes gender, age, location, previous treatment for the lesion, surgery, outcome, recurrence rate and follow-up. 63.1% of the patients underwent cystectomy, 22.5% by cystectomy and carnoy solution, 7.2% by cystectomy, and curettage, 4.5% by cystostomy and 2.7% by partial resection. In this study, no significant differences could be observed regarding the surgical method. Most recurrences occurred with 91.9% in the mandible with an average size of 5.5 cm2 and increased in women. Within a mean follow-up time of 3.6 years the recurrence rate was 36.9%, on average after 36 months. Recurrences were most frequently diagnosed at the age of 31-50 (43.9%). Despite numerous studies, there is still no unanimous opinion on an effective therapy for OKC. However, precise resection of OKC can be facilitated by preoperative 3D-imaging and virtual planning.

A retrospective study of the malignant change of odontogenic keratocyst

The odontogenic keratocyst (OKC) is a common cystic lesion of the maxilla and mandible. Squamous cell carcinoma (SCC) arising from OKC or dysplasia occurring in OKC is rare. This study aimed to explore the incidence and clinical features of the dysplasia and malignant transformation of OKC. In this study, 544 patients diagnosed with OKC were collected. Among them, 3 patients were diagnosed as SCC arising from OKC, and 12 patients were diagnosed as OKC with dysplasia. The incidence was calculated. Clinical features were analyzed by chi-square test. In addition, a representative case reconstructing mandible with vascularized fibula flap under general anesthesia was reported. And cases reported before were reviewed. The incidence of the dysplasia and malignant transformation of OKC, which are highly associated with the clinical features of swelling and chronic inflammation, is about 2.76%. But the relevance between the dysplasia and malignant transformation and age, gender together with pain is not statistically high. All in all, the clinical features of swelling and chronic inflammation can be considered as characteristics of the dysplasia and malignant transformation of OKC. Although the pain isn't statistically relevant, it may be a dangerous clew. Also, combined with earlier literatures, the dysplasia and malignant transformation of OKC shows unique features of radiographs and histopathology.

Clinical indications for radical resection of odontogenic keratocyst: A systematic review

The aim of this study was to identify clinico pathological indications for radical resection of odontogenic keratocysts (OKCs) in the literature and formulate clinical guidelines for the management of OKCs based on these findings. A systematic review of the literature was undertaken in September 2021 in PubMed/Medline, Scopus, Web of Science, Google Scholar, and Cochrane databases. The following MeSH Keywords terms were used in the search strategies: (odontogenic keratocyst) OR (keratocystic odontogenic tumor) OR (primordial cyst) AND (treatment) OR (Radical resection) OR (Resection of OKC) OR (Treatment methods). Eligibility criteria included publications of clinical studies on histologically confirmed OKCs which underwent radical resection. Studies with less than 5 OKCs, experimental studies, epidemiological studies, studies that included orthokeratinized odontogenic cyst, and review papers were excluded. Ten studies on OKCs reporting on segmental or marginal resections were identified and analyzed qualitatively. Of the total of 221 OKCs that underwent radical resection, 67 OKCs were primary, 30 were recurrent, and the remaining were unclear whether they were primary or recurrent. Segmental mandibulectomy was performed in 131 OKCs, marginal mandibulectomy in 87 OKCs, and 3 OKCs were treated by partial maxillectomy. The main indications for radical resection were multilocular appearance, large OKCs (> 5 cm), multiple recurrent OKCs with or without cortical perforation, and malignant transformation. In conclusion, radical resection has its place in the management of OKC. It is indicated when there is an aggressive lesion with bony perforation, involvement of the pterygoid musculature or skull base, and malignant transformation. The surgeon should aim to identify these features to manage OKC appropriately and to prevent multiple recurrences. Clinical guidelines for the management of OKCs are proposed.

Recurrence of odontogenic keratocyst in the buccal space

Odontogenic keratocyst (OKC) rarely appears in the buccal space. It is aggressive and infiltrative, and simple enucleation results in high recurrence. This case report describes an OKC located in the buccal space recurring twice in a 62-year-old man with a 25 mm diameter cystic lesion in the right pterygomandibular space. The multicystic lesion was enucleated. Subsequently, a recurrence was observed, and the gourd-shaped recurrent lesion was also enucleated. The difficulty in detaching the mass from the scar tissue resulted in the perforation of the cystic wall. Thereafter, a second recurrence was observed, and the tissue surrounding the unicystic recurrent lesion was excised. The histopathological features were consistent with those of OKC. The present case is the 11th reported case of OKC in the buccal space and the first with apparent recurrence. Since complete enucleation in the pterygomandibular space is difficult, excision along with the surrounding tissues could prevent recurrence.

Multiple, Multiloculated, and Recurrent Keratocysts of the Mandible and Maxilla in Association with Gorlin-Goltz (Nevoid Basal-Cell Carcinoma) Syndrome: A Pediatric Case Report and Follow-up over 5 Years

Background

We report a case of multiple keratocysts first diagnosed in an 8-year-old boy.

Case report

The incidental radiographic finding of a cystic lesion in an 8-year-old boy led to the surgical enucleation and further diagnosis of a keratocyst associated with a tooth crown. In the course of dental maturation from deciduous to permanent teeth, the boy presented new lesions, always associated with the crowns of teeth. Gorlin-Goltz (nevoid basal-cell carcinoma) syndrome was suspected, and the genetic analysis detected a previously undescribed germline variant in the PTCH1 gene.

Treatment

This included a surgical removal of the cystic lesions, as well as the affected teeth.

Follow-up

Due to the high recurrence rate of the keratocysts, frequent radiological checks were performed over a 5-year period.

Third molar in the orbital floor: A precarious presentation of odontogenic keratocyst-A case report and review of literature

The case illuminates the likelihood of a dental pathology presenting with discrete signs and symptoms and the importance of the differential diagnosis of some incongruent clinical entities. The purpose of this article was to present a case report of odontogenic keratocyst (OKC) arising in the orbital floor, finding the common thread in rare pathology, and highlighting the aberration in our treatment plan by collating all the wealth of information published in the literature.

Topical 5-Fluorouracil is a Novel Targeted Therapy for the Keratocystic Odontogenic Tumor

PURPOSE

The antimetabolite drug, 5-fluorouracil (5-FU), is used in the treatment of various cancers, including basal cell carcinomas (BCCs). The authors hypothesized that keratocystic odontogenic tumors (KOTs) would respond to 5-FU treatment because of their similarities to BCCs in molecular etiopathogenesis.

MATERIALS AND METHODS

An ambispective cohort study of the treatment efficacy of topical 5-FU on KOTs was conducted. Independent variables included the topical application of 5% 5-FU or modified Carnoy's solution (MC) after enucleation and peripheral ostectomy at the University of Toronto from 2006 through 2014. Outcome variables included time to recurrence and peripheral nerve injury. KOT specimens in these patients were immunostained with p53, Ki-67, thymidylate synthetase (TS), thymidylate phosphorylase (TP), and dihydropyrimidine dehydrogenase (DPD) antibodies. Semiquantitative staining scores were calculated for all immunohistochemistry sections examined. Descriptive statistics were computed using Fisher exact test and Kaplan-Meier analysis as appropriate with the P value set at .05.

RESULTS

Thirty-two patients with 32 KOTs were reviewed (41% in women and 59% in men). There were no KOT recurrences in the 5-FU group (n = 11), whereas there were 4 recurrences in the MC group (n = 21; P = .190). There was a significantly lower incidence of inferior alveolar nerve paresthesia with 5-FU treatment (P = .039). Immunohistochemical staining showed upregulation of TP (P < .0001) and DPD (P < .0001) and no change in TS (P > .05) in inflamed KOTs.

CONCLUSIONS

5-FU effectively treats KOTs with less postoperative morbidity than conventional treatment with MC. Low TS and upregulated TP expressions in inflamed KOTs suggest increased 5-FU efficacy in inflamed KOTs. Topical 5-FU is a novel therapy for KOTs and provides a targeted molecular approach to treatment.

Interventions for the treatment of keratocystic odontogenic tumours

BACKGROUND

The keratocystic odontogenic tumours (KCOTs) account for between about 2% and 11% of all jaw cysts and can occur at any age. They are more common in males than females with a male:female ratio of approximately 2:1. Although they are benign, KCOTs are locally very aggressive and have a tendency to recur after treatment. Reported recurrence rates range from 3% to 60%. The traditional method for the treatment of most KCOTs is surgical enucleation. However, due to the lining of the cyst being delicate and the fact that they frequently recur, this method alone is not sufficient. Adjunctive surgical treatment has been proposed in addition to the surgical enucleation, such as removal of the peripheral bone (ostectomy) or resection of the cyst with surrounding bone (en-bloc) resection. Other adjunctive treatments proposed are: cryotherapy (freezing) with liquid nitrogen and the use of the fixative Carnoy's solution placed in the cyst cavity after enucleation; both of which attempt to address residual tissue to prevent recurrence.

OBJECTIVES

To assess the available evidence comparing the effectiveness of interventions for the treatment of KCOTs.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (to 17 March 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2015, Issue 2), MEDLINE via Ovid (1946 to 17 March 2015) and EMBASE via Ovid (1980 to 17 March 2015). We searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomised controlled trials comparing one modality of intervention with another with or without adjunctive treatment for the treatment of KCOTs. Adults, over the age of 18 with a validated diagnosis of solitary KCOTs arising in the jaw bones of the maxilla or mandible. Patients with known Gorlin syndrome were to be excluded.

DATA COLLECTION AND ANALYSIS

Review authors screened trials for inclusion. Full papers were obtained for relevant and potentially relevant trials. If data had been extracted, it would have been synthesised using the fixed-effect model, if substantial clinical diversity were identified between studies we planned to use the random-effects model with studies grouped by action provided there were four or more studies included in the meta-analysis, and we would have explored the heterogeneity between the included studies.

MAIN RESULTS

No randomised controlled trials that met the inclusion criteria were identified.

AUTHORS' CONCLUSIONS

There are no published randomised controlled trials relevant to this review question, therefore no conclusions could be reached about the effectiveness or otherwise of the interventions considered in this review. There is a need for well designed and conducted randomised controlled trials to evaluate treatments for KCOTs.

Skull base tumors: a kaleidoscope of challenge

Resection of skull base lesions has always been riddled with problems like inadequate access, proximity to major vessels, dural tears, cranial nerve damage, and infection. Understanding the modular concept of the facial skeleton has led to the development of transfacial swing osteotomies that facilitates resection in a difficult area with minimal morbidity and excellent cosmetic results. In spite of the current trend toward endonasal endoscopic management of skull base tumors, our series presents nine cases of diverse extensive skull base lesions, 33% of which were recurrent. These cases were approached through different transfacial swing osteotomies through the mandible, a midfacial swing, or a zygomaticotemporal osteotomy as dictated by the three-dimensional spatial location of the lesion, and its extent and proximity to vital structures. Access osteotomies ensured complete removal and good results through the most direct and safe route and good vascular control. This reiterated the fact that transfacial approaches still hold a special place in the management of extensive skull base lesions.

Keratocystic Odontogenic Tumor Surgical Management: Retrospective Analysis on 77 Patients

In 2005 the WHO introduced the former odontogenic keratocyst to the category of benign odontogenic tumours. The change in terminology was based on the observation that the odontogenic keratocyst behaves as a neoplasm and not like a benign cystic lesion. The present paper is a retrospective analysis on the management of keratocystic odontogenic tumor over a period of 11 years (2001–2012) in the Department of Maxillo-Facial Surgery at the University of Rome “Sapienza”, with particular focus on the surgical choices and the relative rates of relapse. The patient population consisted of 34 females and 43 males. Administered treatment modalities consisted of enucleation in 55 cases and radical resection in 22 cases. Nineteen percent of patients who underwent enucleation suffered KCOT relapse. No relapse was observed in the radical resection group with follow-up of 3–7 years. The goals of the treatment include elimination of the pathology and decrease of potential recurrence while minimizing harm to the patient. In the Authors' experience, conservative treatment still encompasses a high rate of recurrence; otherwise, resection provides the lowest recurrence rate, yet causes the most suffering to the patient. The issue surgeons encounter is whether to choose a conservative approach, reducing the morbidity to the patient, knowing that several operations may be required to eliminate recurrence; or being more aggressive and potentially more destructive, at the same time ensuring the best condition to avoid recurrence. Other studies are needed in order to find definitive guidelines for this challenging pathology.

Keratocystic odontogenic tumour arising as a periapical lesion

AIM

To document a case of a keratocystic odontogenic tumour (KOT) involving the apical region in the maxilla mimicking a periapical lesion of endodontic origin.

SUMMARY

Benign and malignant tumours, including odontogenic lesions, can be erroneously diagnosed as periapical radiolucencies. KOTs mimicking periapical lesions of endodontic origin are uncommon, especially when the lesions involve the maxilla. This article describes a 55-year-old man with a well-delimited, oval-shaped, radiolucent lesion, occupying the middle and apical third of teeth 22 and 23. After 30 days, the clinical and radiographic findings remained unchanged and the patient was referred for surgical removal of the lesion. Clinical, radiographic and histopathological features are also discussed and compared with current literature.

Depth of penetration of methylene blue in mandibular cortical bone

BACKGROUND

Surgeons treating keratinizing odontogenic tumors (KOT) and other intrabony lesions frequently use methylene blue as an adjunct in peripheral ostectomy in estimating the depth of bone that has been removed. Depth of methylene blue penetration in cortical bone has not been evaluated.

STUDY DESIGN

Specimens of mandible harvested from 9 fresh unembalmed cadaveric mandibles were stained with methylene blue. A microcaliper was used to measure total thickness of the cortical specimen along with the amount of dye penetration within the cortical block to the nearest 0.1 mm.

RESULTS

Average depth of dye penetration was 0.48 mm in the symphysis. Average dye penetration was 0.53 mm in the body. Average depth of penetration of 0.42 mm in the angle.

CONCLUSIONS

The use of methylene blue as a depth gauge to ensure adequate ostectomy with a single application of the dye may be inadequate to ensure complete removal of lesion from bony wall.

Keratocystic odontogenic tumour (KCOT)--a cyst to a tumour

PURPOSE

The World Health Organization (WHO) has reclassified 'odontogenic keratocyst' (OKC) to 'keratocystic odontogenic tumour' (KCOT) in 2005. Currently, this tumour is classified as a benign neoplasm of odontogenic origin and not as a cyst. This article reviews and discusses history, classification scheme, aetiology and pathogenesis, molecular and genetic basis, incidence, epidemiology and site, clinical features, imaging, histopathology, immunohistochemistry, treatment options, prognosis, recurrence and malignant transformation of KCOT, with emphasis on understanding the basis of reclassification as 'keratocystic odontogenic tumour'.

METHODS

A systematic search and review of the literature was carried out in the online database of the United States National Library of Medicine to identify eligible titles for the study.

RESULTS

Current evidence suggests that the scientific community still continues to use the term 'odontogenic keratocyst' more favourably than 'keratocystic odontogenic tumour'.

CONCLUSION

The online database search indicates that the scientific community still continues to use the term 'odontogenic keratocyst' more favourably than 'keratocystic odontogenic tumour'. At this juncture, where the terminology has changed from a cyst to a tumour, a thorough review of literature on KCOT is presented.

Cell block technique as a complementary method in the clinical diagnosis of cyst-like lesions of the jaw

OBJECTIVE

To evaluate the applicability of the cell block technique as a complementary method for presumptive diagnosis in the analysis of cyst-like aspirates from jaw lesions prior to histopathological diagnosis.

MATERIAL AND METHODS

The sample was made up of 17 cyst-like jaw lesions. After puncture, the aspirates were centrifuged, fixed in formalin, embedded in paraffin and processed. All lesions were biopsied and submitted to histopathological examination.

RESULTS

In 9 cases, the cytopathological analysis using the cell block method showed a predominant presence of erythrocytes, inflammatory cells and few epithelial cells. In the other 8 cases, the cell block technique demonstrated the presence of parakeratin, whose histopathological analysis confirmed the occurrence of keratocystic odontogenic tumors (KOTs).

CONCLUSIONS

According to the studied cases, the cell block method was proven to be a simple, fast and low-cost technique to effectively differentiate KOTs from other lesions with similar clinical and radiographic features. The cell block technique comprises cellular preparations useful to determine a clinical diagnosis and help to develop a therapeutic plan for those lesions.

WITHDRAWN: Comparison of Enucleation With and Without Carnoy Solution for the Treatment of Odontogenic Keratocyst: A Prospective, Randomized Clinical Trial

The Publisher regrets that this article is an accidental duplication of an article that has already been published, doi:10.1016/j.joms.2011.01.034. The duplicate article has therefore been withdrawn.

Interventions for the treatment of keratocystic odontogenic tumours (KCOT, odontogenic keratocysts (OKC))

BACKGROUND

The keratocystic odontogenic tumours (KCOTs) account for between about 2% and 11% of all jaw cysts and can occur at any age. They are more common in males than females with a male:female ratio of approximately 2:1. Although they are benign, KCOTs are locally very aggressive and have a tendency to recur after treatment, reported recurrence rates range from 3% to 60%. The traditional method for the treatment of most KCOTs is surgical enucleation. However, due to the lining of the cyst being delicate and the fact that they frequently recur, this method alone is not sufficient. Adjunctive surgical treatment has been proposed in addition to the surgical enucleation, such as removal of the peripheral bone (ostectomy) or resection of the cyst with surrounding bone (en-bloc) resection. Other adjunctive treatments proposed are: cryotherapy (freezing) with liquid nitrogen and the use of the fixative Carnoy's solution placed in the cyst cavity after enucleation; both of which attempt to address residual tissue to prevent recurrence.

OBJECTIVES

To assess the available evidence comparing the effectiveness of surgical interventions and adjuncts for the treatment of KCOTs.

SEARCH STRATEGY

Databases searched were: the Cochrane Oral Health Group's Trials Register (to 28th July 2010), CENTRAL (The Cochrane Library 2010, Issue 3), MEDLINE (from 1950 to 28th July 2010), and EMBASE (from 1980 to 28th July 2010). The reference lists of all trials identified were cross checked for additional trials. There were no language restrictions and several articles were translated.

SELECTION CRITERIA

Randomised controlled trials comparing one modality of surgical intervention with another with or without adjunctive treatment for the treatment of KCOTs. Adults, over the age of 18 with a validated diagnosis of solitary KCOTs arising in the jaw bones of the maxilla or mandible. Patients with known Gorlin syndrome were to be excluded.

DATA COLLECTION AND ANALYSIS

Review authors screened trials for inclusion. Full papers were obtained for relevant and potentially relevant trials. If data had been extracted, it would have been synthesised using the fixed-effect model, if substantial clinical diversity were identified between studies we planned to use the random-effects model with studies grouped by action provided there were four or more studies included in the meta-analysis, and we would have explored the heterogeneity between the included studies.

MAIN RESULTS

No randomised controlled trials that met the inclusion criteria were identified.

AUTHORS' CONCLUSIONS

There are no published randomised controlled trials relevant to this review question, therefore no conclusions could be reached about the effectiveness or otherwise of the interventions considered in this review. There is a need for well designed and conducted randomised controlled trials to evaluate treatments for KCOTs.