Primordial Odontogenic Tumor; Archival Review of 19380 Cases in a 55-Year Retrospective Study.

BACKGROUND AND OBJECTIVE: Primordial odontogenic tumor is a rare odontogenic tumor reported for the first time in 2014. It was included in the latest edition of World Health Organization classification of Head and Neck Tumors as a new benign mixed epithelial-mesenchymal neoplasm. To date, 26 cases has been reported in literature. The aim of this study was to determine the possible presence of primordial odontogenic tumor in the previously diagnosed cases with myxoid stroma. MATERIALS AND METHODS: This study was a retrospective descriptive study that was concluded in Oral and Maxillofacial Pathology Department, School of Dentistry, Tehran University of Medical Sciences. We reviewed all 19,380 cases from 19,66 to find the lesions with myxoid stroma which were in differential diagnosis with primordial odontogenic tumor. These cases should be associated with an impacted or unerupted tooth and belong to the patients under 20 years old. RESULTS: We find 503 pericoronal lesions with myxoid stroma. Three cases were isolated after recut and reevaluation for finding fulfill histologic features. After immunohistochemical analysis, we find a new case of developing primordial odontogenic tumor associated with odontoma. DISCUSSION: Primordial odontogenic tumor a recently described odontogenic tumor has a well-defined clinicopathological and immunohistochemical profile and should be differentiated from the others pericoronal lesions. It is the first time that this archival review has been done to find probable cases of primordial odontogenic tumor.

Combination of Binary System with Ki67 Immunohistochemical Staining: a Reliable Grading Method for Oral Epithelial Dysplasia.

Statement of the Problem: Oral epithelial dysplasia (OED) is a common potentially malignant lesion of oral cavity that should be managed to prevent likely malignant transformation. Purpose: Here, we present a combination of binary grading system with complementary immunohistochemical (IHC) staining for Ki67 biomarker to provide a reproducible OED grading system. Materials and Method: In this cross-sectional study, seventy out of one hundred OED specimens, which were accompanied by IHC stained microscopic slides for Ki67 antigen were evaluated by four independent oral pathologists. Both three-tier and binary grading systems based on WHO microscopic criteria were employed , blindly in a four-step method with at least two-week interval between each observation. Intra- and inter-observational reliability was assessed using Kappa statistical analysis. Results: OED diagnosis based on binary system showed significant intra-observer reliability comparing to three-tier system without biomarker. Moreover, OED diagnosis based on binary system using Ki67 biomarker showed significant inter-observer reliability comparing to diagnosis in three tier system and based on binary system without Ki67 biomarker showed significant inter-observer reliability comparing to diagnosis based on three-tier system without Ki67. Conclusion: Here, we found that application of IHC staining for Ki67 biomarker in binary system might provide a more reliable grading method for oral pathologist form different educational background.

Developing odontoma arising from calcifying odontogenic cyst: A case report.

Developing odontoma is a rare mixed odontogenic tumor that can arise with other odontogenic lesions. The association of COC with ameloblastic fibro-odontoma is extremely rare. We report an extremely rare case of developing odontoma arising from a calcifying odontogenic cyst in a 17-year-old girl.

Adenoid cystic carcinoma of buccal mucosa: A report of two rare cases and review of literature.

In the oral cavity, adenoid cystic carcinomas of the buccal mucosa are extremely rare. Minor salivary grand adenoid cystic carcinoma should receive aggressive treatment to achieve negative surgical margins to inhibit recurrence.

Central Odontogenic Fibroma Accompanied by a Central Giant Cell Granuloma-Like Lesion: Report of a Case and Review of Literature.

Central giant cell granuloma (CGCG) is a benign non-neoplastic intraosseous lesion mainly found in the anterior mandible. It is characterized by multinucleated giant cells, representing osteoclasts or macrophages. Central odontogenic fibroma (COF) is an uncommon benign lesion of the jaws. It originates from the odontogenic ectomesenchyme. In rare cases, COF may accompany a CGCG. To date, 49 cases of COF accompanied by CGCG-like lesions have been reported in the literature. In this paper, we present another case of COF-CGCG in a 46-year-old female. The lesion was located in the posterior mandible. Excisional biopsy was carried out, and histopathological analysis revealed multinucleated giant cells with numerous strands of odontogenic epithelium. A literature review of previously reported cases was also performed.

Desmoplastic Fibroma of the Jaws: A Case Series and Review of Literature.

Desmoplastic fibroma (DF) is a benign, locally aggressive neoplasm that rarely occurs in the facial skeleton. It usually presents during the first three decades of life. Due to its aggressiveness and high recurrence rate, early diagnosis is imperative, and complete surgical removal of the lesion is the treatment of choice. Herein, we present three cases of DF namely a 2 year-old girl with a mandibular DF, a 9 year-old boy with a maxillary lesion and a 1.5-year old boy with a mandibular DF. Complete clinicopathological information, treatment plan and long-term follow-up of patients are discussed. Histopathologic features of 3 cases revealed non-capsulated spindle cell tumor with fascicular or swirling patterns in incisional biopsy. Immunohistochemical staining was performed to make a definitive diagnosis. Strongly positive nuclear immunoreactivity for ß-catenin confirmed the diagnosis of desmoplastic fibroma in 3 cases. Segmental mandibulectomy, partial maxillectomy and hemimandibulectomy were done for the cases. There was no recurrence in our reported cases after 8 and 11 months and 3 years follow up, respectively. It is noteworthy that despite the aggressive nature of DF, young patients often respond well to wide resection treatment.

Assessment of the Blood Parameters, Cardiac and Liver Enzymes in Oral Squamous Cell Carcinoma Following Treated with Injectable Doxorubicin-Loaded Nano-Particles.

Purpose: Oral squamous cell carcinoma (OSCC) is the most common and most malignant disorder of the oral cavity. Standard cancer treatments have many complications for patients. Nausea, vomiting, and perturbation in blood cells are the most common side effects when using Doxorubicin (Dox) for the treatment of OSCC. Use of Doxorubicin-loaded nano-particles (n-Dox) give rise to increase its biological efficacy and the rapeutic effects. This study assessed the efficacy of the injectable form of the n-Doxon blood parameters and cardiac and liver enzymes compared to the commercial form of Dox in OSCC-induced by 4NQO in rats. Methods: 4-nitroquinoline-1-oxideas was used as a solution in drinking water for inducing OSCC during 14 weeks in male Sprague-Dawley rats. Four groups of animals were categorized randomly: first (OSCC+Dox), second (OSCC+n-Dox), third (OSCC) and, last, healthy animals. Results: Using n-Dox had no harmful effect on the number of white and red blood cells. Thrombocytopenia and leukopenia in animals treated with n-Dox was less than the other groups. Hemoglobin and hematocrit in all treated groups did not differ and were similar to the healthy control. Hepatic and cardiac enzymes did not show any significant difference in any of the groups. Conclusion: The results of this research showed that significant decreases in haematological changes occurred, including leukopenia and anemia, in an animal model of OSCC induced by 4-NQO following use of n-Dox with compare to Dox. Use of n-Dox is better than of Dox for treatment of OSCC.

Evaluation of mast cell counts and microvessel density in reactive lesions of the oral cavity.

Background. Reliable immunohistochemical assays to assess the definitive role of mast cells (MCs) and angiogenesis in the pathogenesis of oral reactive lesions are generally not available. The aim of the present study was to evaluate mast cell counts (MCC) and microvessel density (MVD) in oral reactive lesions and determine the correlation between MCC and MVD. Methods. Seventy-five cases of reactive lesions of the oral cavity, including pyogenic granuloma, fibroma, peripheral giant cell granuloma, inflammatory fibrous hyperplasia, peripheral ossifying fibroma (15 for each category) were immunohisto-chemically stained with MC tryptase and CD31. Fifteen cases of normal gingival tissue were considered as the control group. The mean MCC and MVD in superficial and deep connective tissues were assessed and total MCC and MVD was computed for each lesion. Results . Statistically significant differences were observed in MCC and MVD between the study groups (P < 0.001). MC tryptase and CD31 expression increased in the superficial connective tissue of each lesion in comparison to the deep con-nective tissue. A significant negative correlation was not found between MCC and MVD in oral reactive lesions (P < 0.001, r = -0.458). Conclusion. Although MCs were present in the reactive lesions of the oral cavity, a direct correlation between MCC and MVD was not found in these lesions. Therefore, a significant interaction between MCs and endothelial cells and an active role for MCs in the growth of oral reactive lesions was not found in this study.

Mandibular Fracture Associated with a Dentigerous Cyst: Report of a Case and Literature Review.

Background and aims . Pathological fractures are rare in the maxillofacial region and account for less than 2% of all fractures in this site. They are defined as fractures that take place when bone has been weakened by an underlying pathologic process. Among all pathoses, cysts (although so common in the maxillofacial region) constitute a very small part. Here we report a case of a dentigerous cyst in a 38-year-old man.The cyst was associated with a mandibular second premolar tooth and resulted in a pathologic fracture. Excision of the lesion was performed and bony union was observed after 6 months. In the literature review, only one case of dentigerous cyst causing pathologic fracture was found. In addition to the report of the present case, pathologic fractures associated with all types of odontogenic cysts (totally just 12 cases) are reviewed in this article to provide a comprehensive and detailed collection.

Prevalence of Head and Neck Tumors in Children under 12 Years of Age Referred to the Pathology Department of Children's Hospital in Tabriz during a 10-year Period.

Background and aims. Head and neck tumors are the most common complaints of people referring to different medical sections, especially in children. The aim of this study was to evaluate the prevalence of these tumors in children less than 12 years of age to provide a better perspective for future studies. Materials and methods. All the files in Department of Pathology at Tabriz Pediatric Hospital from 2001 to 2011 were screened for head and neck tumors in children under 12 years of age. Data including age and gender as well as the type, the location, and benign/malignant characteristic of the tumor were recorded. Data were analyzed by SPSS 15 statistical software, using descriptive statistics and chi-square test. Results. A total of 160 cases were identified. Most of the tumors were benign (68%) and most of the tumors occurred in the neck region (41%). The most frequent benign and malignant tumors were lymphangioma and non-Hodgkin lymphoma, respectively. The majority of benign tumors were found in children younger than 2 years old (P=0.007), but there was no age predilection for malignant tumors. Conclusion. According to our results, benign tumors were more prevalent than malignant ones. Although a low rate of benign tumors in males shows that more attention should be paid to the early diagnosis of head and neck tumors.

Therapeutic Efficacy of Orally Delivered Doxorubicin Nanoparticles in Rat Tongue Cancer Induced by 4-Nitroquinoline 1-Oxide.

PURPOSE: Oral cancer is one of the most significant cancers in the world, and squamous cell carcinoma makes up about 94% of oral malignancies. The aim of the present study was to compare the efficacy of doxorubicin plus methotrexate - loaded nanoparticles on tongue squamous cell carcinoma induced by 4NQO and compare it with the commercial doxorubicin and methotrexate delivered orally on seventy SD male rats. METHODS: 70 rats were divided into five groups. During the study, the animals were weighed by a digital scale once a week. Number of mortalities was recorded in the data collection forms. At the end of the treatment, biopsy samples were taken from rat tongues in order to evaluate the severity of dysplasia and the extent of cell proliferation. The results were analyzed using ANOVA, descriptive statistics and chi-square test. RESULTS: No statistically significant difference was found in the mean weight of five groups (p>0.05). No significant relationship was found between groups and mortality rate (P = 0. 39). In addition, there was a significant relationship between groups and the degree of dysplasia (P <0.001). The statistical analysis showed a significant relationship between groups and the rate of cell proliferation (p <0.001). CONCLUSION: The results of the present study showed that the use of doxorubicin plus methotrexate - loaded nanoparticles orally had more therapeutic effects than commercial doxorubicin plus methotrexate.

Immunohistochemical Assessment of Mast Cells and Small Blood Vessels in Dentigerous Cyst, Odontogenic Keratocyst, and Periapical Cyst.

PURPOSE: The aim of this study was to verify the density of mast cells (MCs) and microvessels in odontogenic cysts. Furthermore, the correlation between MCs and microvessels was evaluated to assess the contribution of MCs to angiogenesis and growth of odontogenic cysts. This approach may be a basis for the development of future pharmaceuticals addressed to MCs performance to manage odontogenic cysts. To our knowledge, no study investigating the correlation between MCs and microvessels has been performed to date. METHODS: 60 cases of odontogenic cysts consisting of 20 radicular cysts (RCs), 20 odontogenic keratocysts (OKCs) and 20 dentigerous cysts (DCs) were included in this study. Five high power fields in superficial connective tissue and five high power fields in deep connective tissue were counted for each sample. Moreover, a total mean of ten fields was calculated. RESULTS: RC showed the highest mean numbers of MCs and microvessels (p<0.05). The subepithelial zones of all cysts contained more MCs and microvessels compared to the deeper zones. A statistically significant correlation between the numbers of MCs and microvessels was not observed (r=0.00, p=0.49). CONCLUSION: Although the number of MCs was not significantly associated with microvessels, these cells may be related to the growth of odontogenic lesions, particularly RCs. Further studies on the in vivo functions of MCs will make the concept more clear.

Consistency rates of clinical diagnosis and histopathological reports of oral lesions: a retrospective study.

Background and aims. A correct diagnosis is the most important step in the treatment of oral lesions and each oral lesion has specific clinical features that provide clinical diagnosis; however, some of these features are common among different lesions. In these situations, biopsy and histopathological examination are indicated. The aim of this study was to evaluate the relationship between clinical and histopathological diagnosis of patients referred to the Department of Oral Pathology, Tabriz Faculty of Dentistry, from 2009 to 2011. Materials and methods. In this retrospective study, individual data and clinical findings of 311 patients who had been referred to the Department of Oral Pathology during a three-year period were collected through questionnaires and compared with histopathological reports. Data were analyzed by using chi-squared and Fisher's tests. Results. In 80.7% of the cases the clinical diagnosis of the lesions was consistent with pathology reports. In 19.3% of the cases, the clinical diagnosis of the lesions was not confirmed histopathologically. The greatest consistency was observed for lichen planus (100%) and inflammatory fibrous hyperplasia (epulis fissuratum) (94.3%). Conclusion. Although great consistency rates were observed in this study between clinical diagnoses and pathology reports, there was also a significant disagreement with the literature, indicating that comprehensive clinical examination, high consistency with oral lesion features and effective cooperation between surgeons and pathologists are necessary.

Schwannoma in the midline of hard palate: a case report and review of literature.

Schwannoma is a benign encapsulated slow-growing tumor that originates from Schwann cells of the peripheral nerve sheath. It usually occurs in the head and neck; however, it is rare in the oral cavity. The tongue is the most common site of intraoral schwannomas, followed by the floor of the mouth, palate, gingiva, vestibular mucosa, lips and mental nerve area. We report a rare case of schwannoma in the midline of hard palate with ulcerated surface in a 21-year-old male with a two-month history of a painless swelling on his palate. Clinical, radiographic and histopathological features along with differential diagnosis and treatment are also discussed.

Nucleolar organizer regions in oral squamous cell carcinoma.

BACKGROUND AND AIMS: Several diagnostic methods are being employed to detect benign and malignant lesions, one of which is silver nitrate staining for organizer regions. The number of nucleolar organizing regions (NORs) can be used to show the degree of cell activity or metabolism in pathologic lesions. This study was designed to evaluate NORs as determi-nants of precancerous and squamous cell carcinoma. MATERIALS AND METHODS: A silver colloid technique was applied on paraffin sections of 40 cases of oral squamous cell carcinoma and 25 cases of precancerous lesions; 15 specimens of normal epithelium were selected for the control group. After staining with silver nitrate, argyrophilic nucleolar organizer regions (AgNORs) were counted in 100 epithelial cells in three groups with the use of an oil immersion and ×1000 objective lens. One-way ANOVA and a post hoc Tukey test were used for statistical analysis. RESULTS: The mean numbers and standard deviations of AgNORs were 1.58 ± 0.76 in normal epithelium, 2.1 ± 1.05 in pre-cancerous lesions and 2.43 ±1.33 in squamous cell carcinoma (SCC). There were statistically significant differences in Ag-NORs numbers between the groups (P<0.001) and significant differences in precancerous lesions between dysplastic and non-dysplastic epithelia (P<0.001). The mean AgNORs count per nucleus increased from healthy epithelium to precancer-ous lesion to SCC. CONCLUSION: This study suggests that the silver staining technique for the detection of NORs (AgNOR) can be used to distinguish precancerous lesions and benign and malignant lesions.