Case Of Keratocystic Odontogenic Tumor Research Articles

A Multi-disciplinary Approach in Management of Undetected Odontogenic Keratocyst With Three Years Follow Up - A Case Report

The keratocystic odontogenic tumor (KCOT) is regarded as the most aggressive and recurrent tumor of all. The lesion does not pose any clinical symptoms until significantly large in size. The different treatment modalities are always a matter of dilemma as to which one would yield good results with less recurrence. A Conservative treatment approach for moderately large lesions such as marsupialization and decompression was carried out in this case with regular follow-up sessions. The aim of this case report is to treat cases of KCOT with a conservative surgical approach.

Evaluation of the Connective Tissue Wall in Sporadic Cases of Keratocystic Odontogenic Tumor (KCOT) Using MMP-9 and Confocal Microscopy: A Retrospective Study

Background: Keratocystic odontogenic tumor (KCOT) is an odontogenic lesion which manifests distinct biological behavior. Predominant studies in KCOT attribute this behavior to high epithelial proliferative capacity. Besides, a few studies facet loosely arranged collagen can contribute to the behavior of KCOT. Matrix metalloproteinases (MMP) are enzymes that degrade extracellular matrix components under both physiologic and pathologic conditions. The loosely arranged collagen in connective tissue wall of KCOT could be related to the degree of MMP-9 expression. Aim: To evaluate the arrangement of collagen fibers along with immunoexpression of MMP-9 and to relate to its neoplastic biologic behavior in sporadic cases of KCOT. Materials and Methods: KCOT ( n = 23) and dentigerous cyst (DC) ( n = 15) samples were processed for the following techniques: Masson’s trichrome stain for light microscopy, PMA-PSR stain for confocal microscopy, and MMP-9 for immunohistochemistry. Results: In Masson’s trichrome analysis, correlation of collagen fiber arrangement in the deeper regions with color intensity for KCOT was found to be statistically significant ( P = .033). In confocal microscopy, there was no difference between intensities in KCOT ( P = .990) and DC ( P = .233), respectively. The immunoexpression of MMP-9 in the connective tissue wall of DC (73.3%) was relatively higher than that of KCOT (60.8%). However, on comparison between KCOT and DC in the presence of inflammation, the immunoexpression of MMP-9 was higher in DC (100%) than KCOT (69.9%) and was statistically significant ( P = .028). Conclusion: It was concluded that the loose connective tissue wall in KCOT is because of the inherent nature of the lesion that could facilitate its biologic behavior. If inflammation is present, this could further aggravate the tumorigenic behavior.

Cell proliferation proteins and aggressiveness of histological variants of ameloblastoma and keratocystic odontogenic tumor

ABSTRACTTumors that originate from the epithelium of the odontogenic apparatus are classified as benign or malignant. The proliferative activity could provide a basis for differences in the biologic behavior among the histological variants of ameloblastoma (AM) and keratocystic odontogenic tumor (KCOT). We examined 32 solid AM and 18 KCOT cases. The AM sample comprised 16 cases of follicular AM, six cases of unicystic AM, eight cases of plexiform AM and two cases of acanthomatous AM. Sections were stained with the Ki-67 antibody. Ten representative fields were selected randomly in each section. For AM, peripheral tall columnar cells of tumor islands/nests/cords were selected. For KCOT, fields were selected in the basal and the suprabasal region of the epithelial lining. We counted the average number of Ki-67 positive cells/field for AM and KCOT. AM exhibited Ki-67 expression in peripheral tall columnar cells, whereas KCOT exhibited Ki-67 expression in the basal and suprabasal layer. No significant difference between AM and KCOT was observed; the cellular proliferative activity varied among the subtypes. No significant difference in Ki-67 expression in acanthomatous, cystic and follicular types of AM was observed, although the plexiform type exhibited significantly higher levels than the other three types. High expression of Ki-67 could be a useful prognostic marker for proliferative activity and a prognostic indicator for recurrence rate of AM and KCOT.

Keratocystic odontogenic tumor associated with impacted maxillary third molar extending to the antrum: A challenging diagnosis

Keratocystic odontogenic tumor (KCOT), traditionally known as odontogenic keratocyst (OKC) is a benign intraosseous neoplasm of odontogenic origin with potential for aggressive and infiltrative behavior. Mandible is the most common site of occurrence, while maxillary antrum involvement has been reported as a rare finding. We present a case of KCOT driven from an impacted maxillary third molar, invading the entire right maxillary sinus and the orbital floor; initially misdiagnosed as a dentigerous cyst. The clinical, radiological, and histological aspects of this tumor and its treatment management are discussed.

CLINICAL, RADIOLOGIC, AND THERAPEUTIC FEATURES OF KERATOCYSTIC ODONTOGENIC TUMOR: A SERIES OF FOUR CASES

Herein we report 4 cases of keratocystic odontogenic tumor. Three male patients and 1 female patient, between 40 and 50 years of age, reported to the oral surgery service presenting with swelling on the mandibular body, in the right side of the mandible in 2 patients, and the remaining cases located in the left mandibular body and ramus. CT scan examination revealed anteroposterior intraosseous radiolucent lesion. All cases had incisional biopsy with histopathologic diagnosis of keratocystic odontogenic tumors. The treatment of choice considered the size and anatomic structures compromised by the lesion. Two cases were treated by enucleation and the other 2 with hemimandibulectomy followed by reconstruction with a 2.4 mm titanium fixture plate. The cases have been on follow-up period of 18 months without recurrence.

KERATOCYSTIC ODONTOGENIC TUMOR OF THE MAXILLARY ANTERIOR REGION MASQUERADING AS A RADICULAR CYST

Keratocystic odontogenic tumor (KCOT) is a benign odontogenic neoplasm which is characterized by aggressive behavior and a high recurrence rate. KCOTs have a predilection for the angle and ascending ramus of the mandible. Maxillary KCOTs are usually associated with nevoid basal cell carcinoma syndrome. Very few cases of non-syndromic KCOT crossing maxillary midline have been reported. In this article, we report a rare case of KCOT which presented as a multilocular radiolucency crossing midline and involving periapical area of maxillary incisors. The lesion thus simulated a periapical cyst. However, the lesion was proved to be a KCOT on histopathology. Thus this report highlights the need for histopathological evaluation of periapical lesions for accurate diagnosis and treatment plan.

Correlation between ploidy status using flow cytometry and nucleolar organizer regions in benign and malignant epithelial odontogenic tumors

ObjectiveDifferentiation between the aggressive benign odontogenic tumors and their malignant counterparts is controversial and difficult. While flow cytometry (FCM) allowed DNA analysis in neoplasia, argyrophilic organizer regions (AgNORs) number and/or size in a nucleus are correlated with the ribosomal gene activity and therefore with cellular proliferation. The aim of this research was to study the diagnostic accuracy of FCM and AgNORs staining in differentiating between benign and malignant epithelial odontogenic tumors and to correlate between these two interventions. DesignSixteen benign cases [8 cases of ameloblastoma (AB) and 8 cases of keratocystic odontogenic tumor (KCOT)] and 13 malignant epithelial odontogenic tumors [8 cases of ameloblastic carcinoma (ABC) and 5 cases of clear cell odontogenic carcinoma(CCOC)] were included in the current study. For FCM analysis, a single cell suspension from Formalin fixed paraffin-embedded (FFPE) tumors was prepared according to a modified method described by Hedley (1989) and AgNORs staining were performed in accordance to the Ploton protocol (1986). Analysis of AgNORs was performed using both quantitative and qualitative methods. ResultsThe work revealed that all the examined tumors were diploid, except for 40% of CCOC cases. The S-phase fraction (SPF) value, AgNORs count and AgNORs area/cell showed statistically significant difference on comparing benign and malignant groups. A weak positive correlation was observed between SPF and AgNORs count. ConclusionThe SPF value was considered to be more sensitive and specific in differentiation between aggressive benign and malignant epithelial odontogenic tumors in comparison to AgNORs counting.

COMPARATIVE STUDY OF CALRETININ EXPRESSION IN ODONTOGENIC CYSTS AND TUMORS

Calretinin is a calcium-binding protein with molecular weight of 29 kDa (KiloDalton). It is expressed in a variety of normal and tumorigenic tissues. Its expression in odontogenic epithelium during odontogenesis and in neoplastic odontogenic tissues has been demonstrated. This study was undertaken to evaluate the expression of Calretinin in a group of odontogenic cysts and tumors. The expression of Calretinin was evaluated immunohistochemically in 42 samples including 8 cases of periapical cyst, 7 cases of dentigerous cyst, 7 cases of keratocystic odontogenic tumor, 8 cases of solid (multicystic) ameloblastoma, 6 cases of unicystic ameloblastoma and 6 cases of adenomatoid odontogenic tumor. Positive immunohistochemical reaction was found in all cases of solid ameloblastoma (100%), in 4 cases of unicystic ameloblastoma (67%) and 4 cases of keratocystic odontogenic tumors (57%) whereas none of the other odontogenic cysts and adenomatoid odontogenic tumors included in this study showed reactivity. Intensity was higher in the ameloblastomas compared with the keratocystic odontogenic tumors. On the basis of these results, it is suggested that calretinin might be used as a specific immunohistochemical marker for the ameloblastomas and could play an important role in the differentiation of aggressiveness of different odontogenic tumors.

A recurrence case of keratocystic odontogenic tumor

A recurrence case of keratocystic odontogenic tumor

Expression of astrocyte elevated gene-1 protein in ameloblastomas, keratocystic odontogenic tumors, and dentigerous cysts.

Benign epithelial odontogenic tumors such as ameloblastoma and keratocystic odontogenic tumor (KCOT) may exhibit an aggressive clinical course reminiscent of malignancies. Recent studies have indicated that astrocyte elevated gene-1 (AEG-1) is highly expressed in a variety of malignant neoplasms and its overexpression is associated with tumor invasion, metastasis, and poor survival. However, the role of AEG-1 in odontogenic tumors and cysts is still undiscovered. Immunohistochemical staining of AEG-1 was performed in 42 cases of ameloblastoma, 29 cases of KCOT, and 19 cases of dentigerous cyst. Correlations between AEG-1 expression and clinical parameters of ameloblastomas or KCOTs were statistically analyzed. AEG-1-positive staining was found in 37 (88%) of 42 ameloblastomas and in 24 (83%) of 29 KCOTs. None of 19 dentigerous cysts were positive for AEG-1 protein. For ameloblastomas, AEG-1 protein expression was significantly higher in ameloblast-like cells than in stellate reticulum-like cells (P = 0.003). For KCOTs, AEG-1 protein was diffusely expressed in all lining epithelial cells except the superficial parakeratinized cells. Moreover, the frequency of cortical plate perforation was significantly higher in ameloblastomas with high AEG-1 expression than in ameloblastomas with low or negative AEG-1 expression (P = 0.043). Significantly higher expression of AEG-1 protein in ameloblastomas and KCOTs than in dentigerous cysts and significantly greater frequency of cortical plate perforation in high AEG-1-expressed ameloblastomas than in low or negative AEG-1-expressed ameloblastomas may imply the high potential of AEG-1 to serve as a locally invasive biomarker and a target for novel therapy.

Interaction of stromal and microvascular components in keratocystic odontogenic tumors

Little is known about the interaction of stromal components in odontogenic tumors. Thus, the aim of this study was to investigate mast cells (MCs), myofibroblasts, macrophages, and their possible association with angiogenesis and lymphangiogenesis in keratocystic odontogenic tumors (KCOTs). Thirty cases of KCOTs were included and analyzed by immunohistochemistry for mast cell tryptase, α-SMA, CD34, CD163, and D240. For comparative purpose, 15 radicular cysts (CRs) and 7 pericoronal follicles (PFs) were included. There was an increase in MCs for RCs and this difference was significant when they were compared to KCOTS and PFs. A significant increase in the density of MFs was observed for KCOTs when compared to RCs and PFs (P = 0.00). No significant difference in CD163-positive macrophages (P = 0.084) and CD34-positive vessels (P = 0.244) densities was observed between KCOTs, RCs, and PFs, although KCOTs showed a higher density of all proteins. Significant difference in lymphatic vessel density was observed for KCOTs when compared to RCs and PFs (P = 0.00). Positive correlation was observed between mast cell tryptase and CD34 in KCOTs (P = 0.025). A significant interaction between the MC population and CD34-positive vessels in KCOTs supported the hypothesis that MCs and blood vessels contribute to the stromal scaffold of KCOT.

Immunohistochemical expression of vascular endothelial growth factor in keratocystic odontogenic tumor, dentigerous cyst, and radicular cyst: A comparative study.

Background:Cyst and tumors arise from tissue remains of odontogenesis, these interactions have been considered to play an important role in the tumorigenesis of odontogenic lesions. The connective tissue stroma has an essential role in the preservation of epithelial tissues and minor alterations in the epithelium are followed by corresponding changes in the stroma, such as angiogenesis. Vascular endothelial growth factor (VEGF) is considered the first factor which maintains its position as the most critical driver of vascular formation and is required to initiate the formation of immature vessels, with this aim, present study was executed to evaluate VEGF expression in kertocystic odontogenic tumor, dentigerous cyst and radicular cyst (RC).Materials and Methods:A retrospective study was carried out comprising a total of 31 cases; 13 cases of keratocystic odontogenic tumor (KCOT), nine cases of dentigerous cyst (DC) and nine cases of RC. The sections were stained immunohistochemically with VEGF antibody and were evaluated for the presence and intensity of the immuno reactive cells. Statistical analysis was carried out using Chi-square test to inter-compare the VEGF expression between KCOT, DC, and RC.Results:VEGF expression in the epithelium and connective tissue was significantly higher in KCOT compared to dentigerous and RC. One case of KCOT with carcinomatous change also revealed positive results for the VEGF expression in the dysplastic epithelium, tumor islands, and connective tissue. The significant difference was observed on inter-comparison of the VEGF expression in the connective tissue of KCOT and DC, whereas no significant difference was observed in the VEGF expression in the connective tissue of KCOT and DC.Conclusion:The present study data supports the literature finding that angiogenesis can be important in the progression and enlargement of odontogenic cysts similarly to what occurs in neoplastic conditions and further it can be concluded that the higher positivity for VEGF of KCOT could help to explain in part the aggressive biological behavior of the lesion. The stroma of KCOT could be regarded not only as a structural support of the cyst wall but also as playing a part in the neoplastic behavior of cyst.

Unusual presentation of keratocystic odontogenic tumor: Two case reports

Keratocystic odontogenic tumor (KOT) is a common odontogenic cyst with aggressive behavior with a high recurrence rate. Features that predict recurrence of KOT are thin friable epithelium which is difficult to enucleate and presence of satellite cysts in the fibrous wall. Most of the lesions grow in an anteroposterior direction without causing any bony expansion. Here, we report two cases of KOT with different clinical presentation.

Odontogenic Keratocyst Tumor: A Case Report and Literature Review

First described by Philipsen in 1956, the odontogenic keratocyst is characterized by a large squamous keratinization of its border, an aggressive growth and a high recurrent rate. It is now designated by the World Health Organization as a keratocystic odontogenic tumour (KOT). Clinically, the KOT is manifested by an asymptomatic growth. Radiographically, it appears as a well-defined uni-locular or multilocular osteolytic lesion. The diagnostic approach is based on a combined analysis of the medical history, the clinical appearance and the radiographic appearance. The diagnosis may be confirmed by the anatomical pathology report. Finally, treatment consists of surgical excision and follow up is characterized by a high rate of recurrence. The authors report a case of keratocystic odontogenic tumor of the upper jaw and review the various diagnoses, therapeutics and follow up aspects of this type of tumors.

Keratocystic odontogenic tumor: A biopsy service's experience with 104 solitary, multiple and recurrent lesions.

BackgroundKeratocystic odontogenic tumor (KCOT) is a clinically significant cystic lesion of odontogenic origin. This study aimed to retrospectively review and describe the clinicopathologic features of KCOT and to objectively compare the clinical and histological features of solitary, multiple and recurrent KCOT in a Saudi Arabian population.Material and MethodsBiopsy request forms, pathology records and archival materials (all histological slides) of 104 cases of KCOT from 75 patients were retrieved. Demographic and clinical details as well as histological evaluation were analyzed and compared between the 3 groups using chi-squared or Mann-Whitney tests of association as appropriate.ResultsSignificant differences were noted in the age of presentation, location and association with impaction between multiple and solitary cases. Histologically, there was a difference in the mitotic count, presence of satellite cysts and proliferating odontogenic epithelium between solitary and multiple lesions. There was no difference between the KCOT that later recurred and solitary lesion which did not recur even when matched clinically for age, sex and location. There were differences when solitary KCOT that later recurred or recurrent KCOT were compared with multiple lesions. Multiple lesions still had more significant proliferative activity parameters than solitary recurrence-related KCOT.ConclusionsKCOTs in Saudi Arabians are not different from those reported from other parts of the world. Clinical and histological analyses showed multiple KCOT is different from its solitary recurrent or non-recurrent counterparts and has a higher proliferative activity than both. Clinicohistologic features alone cannot wholly explain the behavior of KCOT. Key words:Descriptive study, keratocystic odontogenic tumor, odontogenic keratocyst, solitary, multiple, recurrent.

E-cadherin regulators are differentially expressed in the epithelium and stroma of keratocystic odontogenic tumors.

The epithelial-mesenchymal transition (EMT) is the process where cells lose their epithelial features and acquire properties of typical mesenchymal cells. The dissociation of tumor cells due to changes in cell-cell adhesion is one of the key principles of tumor invasion and EMT. Thus, the knowledge of the molecular features of EMT in keratocyst odontogenic tumor (KOT) can provide useful markers to aid in the diagnosis and prognosis and perhaps contribute to an alternative therapeutic approach as it shows an aggressive clinical behavior and high recurrence rates. This study aimed to evaluate the EMT in KOT by the immunoexpression of E-cadherin, N-cadherin, Snail, and Slug and comparing to radicular cysts and dental follicles. Thirty-two KOTs, 15 radicular cysts, and 08 dental follicles were used for immunohistochemistry, evaluating the extent, intensity, labeling pattern, cellular compartment in the epithelium and stroma, and the presence of inflammation. E-cadherin was preserved in most cases of keratocystic odontogenic tumor. N-cadherin was increased in the tumor epithelium, a result that was positively correlated with the heterogeneous and nuclear immunoexpression of Slug in the epithelium; Slug also correlated with high Snail immunoexpression. N-cadherin was positively correlated with Slug in the stroma of keratocystic odontogenic tumors. The high immunoexpression of Snail and nuclear Slug in keratocystic odontogenic tumors suggests these proteins as transcription factors without necessarily participating in 'cadherin switching'. However, the knowledge of their induction of the epithelial-mesenchymal transition in odontogenic tumors is still limited.

Keratocystic Odontogenic Tumor in the Infraorbital Region: Case Report

Keratocystic odontogenic tumor (KOT) is a benign but locally aggressive tumor originating from the cellular remnants of dental lamina. It is frequently located in the posterior mandible, being rare in the anterior maxilla. A 17-year-old female presented to our department of oral and maxillofacial surgery with painful volume increase in the right infraorbital region. Computed tomography showed an image consistent with a lesion surrounding the crown of tooth #13, in the infraorbital region. The tooth was extracted, and the lesion was completely removed by local surgical excision. Histopathological examination of the lesion resulted in a diagnosis of KOT. The patient progressed well and without recurrence. This particular topography is rare among cases of KOT.

Keratokistik odontojenik tümör: 64 vakalık retrospektif çalışma

Aim: The purpose of this retrospective study was to evaluate the clinicopathological features of 64 patients with keratocystic odontogenic tumor (KCOT). Materials and Methods: The patients ranged in age at the time of diagnosis from 8 to 74 years (mean: 38.20 ± 16.71). Postoperative follow-up period was 3-8 years (mean time 4.76 ± 1.10). This research was carried out on panoramic radiographs and histopathological samples. Data such as gender, age, treatment methods, location of the tumor, presence of impacted teeth and its histological features were subjected to descriptive statistical analyses with the statistical software program. Results: Of the 64 analyzed cases of KCOT, 68.8% of them were men and 31.2% were females (male-to-female ratio was 2.2:1). It was observed that KCOT peaked in the third and fifth decade of life (23.4%-20.3%). The incidence of KCOT was higher in the mandible than in the maxilla (76.6%-23.4%). There was recurrence in nine out of 64 subjects (14.1%) in the follow-up period. The recurrence was more often found in posterior mandible. It is noteworthy that in 9 recurrent subjects, 7 lesions were parakeratotic and 4 lesions were associated with daughter cysts. Conclusion: Although there are several studies about KCOT in the literature, the choice of treatment modalities remains controversial. In recurrent subjects, more aggressive therapy approaches should be considered. Periodic controls and aggressive treatment approaches may be effective in the prevention of recurrences.

Expression of Bcl-2 and epithelial growth factor receptor proteins in keratocystic odontogenic tumor in comparison with dentigerous cyst and ameloblastoma.

Background:Keratocystic odontogenic tumor (KCOT) is a developmental odontogenic cyst on which various investigations have been focused due to its biological activities, high tendency to recur and different growth mechanisms in comparison with other cystic lesions. Previous studies have shown different biological and proliferative activities for the lining epithelium of KCOT. The aim of this study was immunohistochemical evaluation of Bcl-2 and epidermal growth factor receptor (EGFR) expression in KCOT compared with dentigerous cyst and ameloblastoma.Materials and Methods:Formalin-fixed and paraffin-embedded tissue sections of 16 cases of KCOT, 16 cases of dentigerous cyst and 16 cases of ameloblastoma were immunohistochemically analyzed to determine Bcl-2 and EGFR proteins’ expression. Biotin-Stereotavidin method was used. It was observed by two oral pathologists separately, and the data were analyzed by Mann–Whitney and Kruskul–Wallis. P < 0.05 was considered as significant.Results:Regardless of staining intensity, all cases of ameloblastoma and KCOT except dentigerous cases were positively stained for Bcl-2. Expression of Bcl-2 was higher in the peripheral layer of ameloblastoma and basal layer of KCOT. Furthermore, all cases of ameloblastoma and dentigerous cysts except KCOT samples were positively stained for EGFR. Expression of EGFR was higher in the peripheral layer of ameloblastoma and basal layer of dentigerous cysts.Conclusion:According to the expression of — Bcl-2 in ameloblastoma and KCOT, and no expression of EGFR in KCOT, it can be concluded that the biological activity and growth mechanisms of KCOT are different compared with other cystic lesions. However, the aggressive potential of KCOT is not as severe as that of a neoplasm such as ameloblastoma.

Diagnostic dilemma: Radicular cyst or keratocystic odontogenic tumor?

Keratocystic odontogenic tumor was previously considered as a common cyst of developmental origin but now it is considered as a tumor of the oral cavity with high recurrence rate and it has an ability to mimic other jaw cysts. Present study is a case report of a 19 year old male presenting with apainful swelling in right lower face region. On clinical and radiographic examination, a provisional diagnosis of Radicular cyst was given. Histopathological examination revealed Keratocystic Odontogenic Tumor. KOT may look similar to endodontic lesion. The lesion was successfully treated by complete enucleation. The aim of the study is to report and distinguish a case of keratocystic odontogenic tumor simulating Radicular cyst because of its aggressive behavior and high recurrence rate.