Immunohistochemical comparison of E-cadherin expression in oral lichen planus with and without dysplasia

Objectives E-cadherin is a transmembrane glycoprotein, which is responsible for cell adhesion and its expression decreases in dysplastic lesions. This study aimed to assess the expression of this marker in oral lichen planus (OLP) with and without dysplasia to assess its potential for use as a predictor of malignant transformation.Methods This descriptive, cross-sectional study was conducted on 44 OLP specimens using immunohistochemistry (IHC) by streptavidin- biotin technique. For this purpose, E-cadherin antibody was used and the intensity score (IS), proportional score (PS) and total score (TS) were calculated. Data were analyzed using SPSS version 21. The relationship between the intensity of expression of E-cadherin and dysplastic changes was assessed using the Mann Whitney U test. P < 0.05 was considered significant.Results The TS of E-cadherin expression was 3 to 6 and 3 in the superficial and deep layers of 100% of specimens with dysplasia, respectively. The TS of E-cadherin expression was 3 to 6 in the superficial layer of 82.5% of specimens and 3 in deep layers of 81.2% of specimens without dysplasia. According to the Mann Whitney U test, the expression of E-cadherin in the superficial (P = 0.90) and deep (P = 0.35) layers was not significantly different between the two groups of OLP with and without dysplasia.Conclusion No significant difference was found in the expression of E-cadherin in OLP specimens with and without dysplasia. It may be concluded that in contrast to other preneoplastic lesions, dysplastic changes of OLP do not follow other malignant transformation patterns in the oral mucosa

Immunohistochemical Expression of PCNA and Ki-67 in Periapical Granuloma and Radicular Cyst

Objectives: Periapical Granulomas (PGs) and Radicular Cysts (RCs), as the most common odontogenic lesions have yet unclear pathogenesis. This study was aimed to compare PCNA and Ki-67 expression in PGs and RCs and evaluate their possible relationship with two lesions.Methods: In this cross-sectional descriptive study, twenty PGs and twenty RCs were evaluated immunohistochemically using an anti-PCNA and anti-Ki-67 polyclonal antibodies. PCNA+ and Ki-67+ cells were counted in connective tissue wall and epithelial lining (in RCs). Statistical analysis was performed by using Mann-Whitney U test and Spearman’s rank correlation coefficient.Results: In PGs, percentage of PCNA and Ki-67 expression were found 70% and 30%, respectively; In RCs, PCNA and Ki-67 expression were observed 90% and 55%, respectively. Additionally, in RCS, Immunoexpression of PCNA (85%) and Ki-67 (60%) were detected at epithelial lining area. The positive immunoexpression of PCNA in RCs was greater than PGs (p<0.05).Conclusion: Immunoexpression of PCNA and Ki-67 were detected in both lesions which may be mentioned as valuable markers for the prediction of biologic behavior of PGs and RCs

Odontogenic Cysts: A 10-Year Retrospective Study in an Iranian Population

Objectives: The purpose of this study was to determine the frequency of all odontogenic cysts (OCs) along with age range, gender distribution, and the site of involvement over a 10-year period (March 2001 to March 2011) and to compare these data with findings from other surveys.Methods: The archives of departments of oral and maxillofacial pathology from Shahid Beheshti and Tehran University of Medical Sciences were retrieved and analyzed for demographic data such as age, gender, location and histopathological diagnosis of OCs.Results: Of the 8,563 biopsy samples that were received, 1,518 (17.7%) were diagnosed as OCs. Radicular cyst was the most common diagnosis (33.2%), followed by dentigerous cysts (24.1%), and odontogenic keratocysts (18.6%). OC occurred 59.3%, 40.6% in male and female respectively. Mandibular involvement was 62.4% while in maxilla was 37.6%.Conclusion: Our study provided demographic data on a large series in Iran, a Southwest Asian country. In our study, radicular cysts, the most common OC, had a lower frequency compared to that reported in most other studies. On the other hand, calcifying OCs seem to be more prevalent in the Iranian population compared to other populations male to female to female ratio was 1.45:1

Ortho keratinized Odontogenic Cyst of Mandible: A Rare Case Report

Objective: The Ortho keratinized Odontogenic Cyst (OOC) is a rare lesion originates from dental lamina and clinically, it may be mistaken for many other odontogenic cysts and Tumors. Microscopically, It should be distinguished from KCOT because of differences in biologic behavior and histologic features.Case: An interesting case of OOC arising in the edentulous mandibular right first premolar region of a 55-year-old woman is reported. Under the initial clinical diagnosis of a residual cyst, the excisional biopsy was performed. Because of detection of an orthokeratinized epithelium lining, a definite diagnosis of OOC was made.Conclusion: Microscopic examination is crucial for making the correct diagnosis of such lesions, therefore establishing patients' prognosis accurately

Extrafollicular Cystic Adenomatoid Odontogenic Tumor of the Maxilla: a Rare Challenging Case Report with Review of the Literature

Adenomatoid odontogenic tumor is a non-aggressive slow growing epithelial odontogenic tumor with varied clinical and microscopic features. This neoplasm rarely appears as a completely cystic lesion histopathologically; therefore, oral pathologists should be aware of the various histopathologic types of this lesion. The main objective of this case report is to present a rare challenging case of maxillary extrafollicular cystic adenomatoid odontogenic tumor affecting a 28-year-old male

Are CD68 and Factor VIII-RA Expression Different in Central and Peripheral Giant Cell Granuloma of Jaw: An Immunohistochemical Comparative Study

Objective: Central giant cell granuloma and peripheral giant cell granuloma of the jaw and oral cavity are identical in histopathologic features, although they are different in pathogenesis and clinical behavior. The aim of present study was to compare CD 68 and factor VIII related antigen (VIII-RA ) immunoreactivity in central giant cell granuloma and peripheral giant cell granuloma to determine the biologic nature and clinical behavior of these lesions which may lead to a better or new treatment modality. Material and Method: CD68 and factor VIII-RA expression were examined immunohistochemically in 22 cases of central giant cell granuloma (10 aggressive and 12 non- aggressive ) and 19 cases of peripheral giant cell granuloma. The Kruskal-Wallis test followed by the Dunn test was used for data analysis. Results: CD68 expression was observed in approximately 100% of multinucleated giant cells and 50% of mononuclear cells. Overexpression of factor VIII-RA in the endothelial cells of capillary like vessels in the periphery of the lesions was prominent. A statistical significant difference for CD68 intensity score in mononuclear cells among three groups (P=0.016) was observed. Indeed, factor VIII-RA intensity score in the endothelial cells of central giant cell granuloma and peripheral giant cell granuloma showed significant difference (P=0.004). Conclusion: These findings support the histiocyte/macrophage nature of multinucleated giant cells and mononuclear cells. Overexpression and high intensity score of CD68 in mononuclear cells and the high intensity score of factor VIII-RA in endothelial cells represent less aggressive behavior in central giant cell granuloma

Diagnostic and Biological Significance of Immunohistochemical Expression of Osteopontin and Ki67 in Fibro-osseous lesions of jaws

Background and Aim: Fibrous dysplasia (FD) and ossifying fibroma (OF) are the most important fibro-osseous lesions (FOLs) of the jaws with similarities in radiographic and morphological features while showing completely different biological behavior. Limited studies have been evaluated immunohistochemistry markers, such as osteopontin (OPN) and osteocalcin to help differentiate these two lesions. This study aimed to assess the immunoexpression of OPN and Ki67 as potential markers for differentiation of different FOLs. Materials and Methods: This cross-sectional study was conducted on 12 FD, 19 OF, and eight FOL samples retrieved from the archives of the department of oral pathology. The specimens were examined immunohistochemically using streptavidin-biotin method for OPN and Ki67. The intensity score (IS), proportional score (PS) and total score (TS) were assessed in hard and soft tissue matrix and in mesenchymal cells for Ki67. The data were analyzed by independent samples Kruskal-Wallis. Results: Osteopontin showed positive immunoreaction in both stromal and trabecular components of all FDs and OFs. Among the scores, PS and TS of bone trabeculae were significantly different in FD and OF (P=0.005). Nevertheless, no significant difference was observed in Ki67 expression in mesenchymal cells (P=0.880) and OPN scores in soft tissue matrix between the lesions; their P-value were 0.336, 0.340 and 0.415 for IS, TS, and PS, respectively. Conclusion: Osteopontin can serve as a useful marker for differential diagnosis of FD and OF. However, we suggest evaluation of other NCMPs, especially functionally similar molecules such as bone sialoproteins (BSPs) in FOLs for differential diagnosis

Asymptomatic Osteoblastoma of the Mandible: A Rare Case Report

Osteoblastoma is a rare solitary osteoblastic bone neoplasm. It is characterized by proliferation of osteoblasts forming trabeculae within a vascular fibrous stroma. There is a variety of jaw bone lesions with very close clinical, radiological and microscopic interrelations, which make diagnosis more challenging. Familiarity with these rare bony lesions is vital for oral pathologists. This report presents a new case of asymptomatic mandibular osteoblastoma occurring in a 43-year-old mal

The correlation between p16 expression and INK4a locus mutation with grades and stages in oral squamous cell carcinoma

Objective: p16INK4a is a tumor suppressor gene playing a critical role. Researches have indicated the gene to be altered in oral squamous cell carcinoma. Present studies have tried to assess the correlation between p16INK4a expression and INK4a locus mutation in relation to grades and stages of this tumor. Materials and Methods: Expression of p16INK4a was studied immunohistochemically in 58 oral squamous sell carcinoma samples and INK4a locus mutation was determined by polymerase chain reaction (PCR) and conformation sensitive gel electrophoresis (CSGE). Results: Expression of p16INK4a was higher in stage1 compared to stage 2, 3, and 4 (P = 0.234). The difference was not significant in grade 1, 2, and 3 (P = 0.671). The average values of total score (TS) were significantly higher in stage1 compared to stage 2, 3, and 4 (P = 0.035). The average values of complete score (CS) were higher in stage 1 compared to stage 2, 3, and 4 (P = 0.061). The research did not show a significant correlation between lymph node involvement and p16INK4a expression (P = 0.491). It seems that 5.1% (3/58) of samples have mutation in INK4a locus. Conclusion: Loss of p16INK4a expression occurred in initial stages of oral squamous cell carcinoma. Evaluation of TS and CS for p16INK4a might be a useful clinical indicator concerning the tumor. However, gene mutation is believed to have minor rate of genetic alteration in carcinogenesis

Case Report Recurrent Peripheral Calcifying Cystic Odontogenic Tumor (Calcifying Odontogenic Cyst)

ABSTRACT Peripheral calcifying cystic odontogenic tumor (PCCOT) is a rare odontogenic lesion, which represents about 1% of jaw cysts. Here we report clinicopathologic, radiographic and CT scan images of a new case of recurrent large PCCOT located in mandibular gingiva in a 77-year-old male with history of a nodular mass in the same area, which had been completely excised 3 years ago. In reviewing the literature, we found 55 previous reported cases with a mean age of 48.8 yr at the time of diagnosis. A majority of cases appear as a circumscribed nodule less than 1.5 cm in greatest diameter, without bony involvement. No case larger than 4cm in diameter has been reported. Only one case of recurrent PCCOT was seen in reported cases