Clear cell odontogenic carcinoma (CCOC) is an extremely rare odontogenic neoplasm; Only a few cases have been reported in the English literatures. It displays a propensity for the mandible, most commonly presenting in the fifth to seventh decades, with a female predilection. The clinical and radiological manifestations are multiple and the diagnosis is histological. Histological feature is of large islands and strands of uniform cells with round or ovoid nuclei and clear cytoplasm. Clinically, painless swelling is the most common symptom, followed by pain, teeth mobility, and paresthesia. CCOC has a good prognosis after surgery. This case report presents the histopathological and clinical features of CCOC excised from the mandible.

Intravascular papillary endothelial hyperplasia (IPEH) is an unusual reactive benign lesion of vascular origin caused by endothelial cell proliferation, which rarely occurs in oral cavity. IPEH appears in various forms because it has non-specific clinical presentation, so it can be misdiagnosed as a malignant lesion.Therefore, it is important to make a differential diagnosis by understanding the characteristics of this lesion.We report a case of IPEH in a 22-year-old Korean female patient, discussing about differential diagnosis and treatment. This report presents review of literature and describes a case of IPEH. Key words : Intravascular papillary endothelial hyperplasia, Masson’s tumor, Tongue

Lipoma is the most common soft tissue mesenchymal tumor which grows slowly. [1] [2] Intraoral lipomas are rare and have been reported in approximately 1 to 4% of all neoplasm in various literature. [2-5] Oral lipomas mostly develop slowly without symptoms, [6] and predominantly affect the buccal mucosa, floor of mouth, tongue and lip. [3] Material and Methods: A 71-year old male presented with asymptomatic swelling on tongue. On the clinical examination, there were various size of three swelling areas on the dorsum of tongue. Result: All lesions were surgically removed via intraoral approach under general anesthesia. They were soft and yellowish in color. All of the specimens has histologically revealed as typical lipomas. Conclusion: It is a report of tongue lipomas as a rare site, with clinical, histological and radiographic features. Also, there were several reports of a large or huge lipoma in oral cavity, however there were no report of multiple lipomas on the tongue. So, authors report the rarity of it.

Pleomorphic adenoma (PA) is the most common benign salivary gland tumor. Being pleomorphic, its histologic characteristics can be considerably varied, showing epithelial (ductal and non-ductal) cells and mesenchyme-like tissues (chondroid, myxoid, and osseous). Here, we present a rare case of a 76-year-old female presenting with a 2.0 cm PA with an epidermoid cyst of minor salivary glands on the soft palate.

The case of an intraosseous leiomyoma in a 22-year-old man is presented. The tumor was incidentally discovered during dental radiographic examination for endodontic treatment of mandibular first molar. Radiographic examination revealed a well-defined unilocular radiolucency between the roots of mandibular left canine-first premolar, measuring approximately 1.9 x 1.8 cm and perforation of the buccal cortical plate. Histological and immunohistochemical examination was diagnostic of intraosseous solid leiomyoma. Here, we report a rare case of leiomyoma of the mandible, together with conventional histopathologic and immunohistochemical findings.

Calcifying Epithelial OdontogenicTumor(CEOT), also known as Pindborg tumor is a rare lesion comprising about 1% of all odontogenic tumors mostly rising in the posterior of the mandible. It generally occurs in patients between 30-60 years old. This paper describes a case of CEOT in a 17 year-old female affecting the right mandible. Histopathologic findings showed sheets of polygonal tumor cells and pools of amorphous, eosinophilic amyloids with calcifications. 1 year after resection of the tumor, no clinical and radiographic signs of recurrence were observed.

This study aimed to test a convolutional neural network (CNN) in two different settings of training and testing data. Panoramic radiographs were selected from 1170 female dental patients (mean age 49.19 ± 21.91 yr). The cortical bone of the mandible inferior border was evaluated for osteoporosis or normal condition on the panoramic radiographs. Among them, 586 patients (mean age 27.46 ± 6.73 yr) had normal condition, and osteoporosis was interpreted on 584 patients (mean age 71.00 ± 7.64 yr). Among them, one data set of 569 normal patients (mean age 26.61 ± 4.60 yr) and 502 osteoporosis patients (mean age 72.37 ± 7.10 yr) was used for training CNN, and the other data set of 17 normal patients (mean age 55.94 ± 4.0 yr) and 82 osteoporosis patients (mean age 62.60 ± 5.00 yr) for testing CNN in the first experiment, while the latter was used for training CNN and the former for testing CNN in the second experiment. The error rate was 15.15% in the first experiment and 5.14% in the second experiment. This study suggests that age-matched training data make more accurate testing results.

Odontogenic keratocyst (OKC), also known as keratocystic odontogenic tumor (KCOT), is an emerging odontogenic tumor originating from the dental lamina. It is an aggressive lesion with a squamous epithelium and a recurrence rate of 15-35%. Radiologically, there is a clear, smooth, or shell-like border showing a unilocular or multifocal, polycystic radiographic picture. Hard tissue formation in OKC is a very rare phenomenon and occurs in the form of dystrophic calcification, cartilaginous tissue or dentinoid. In this article, we report the case of OKC with calcification. OKC with radiopaque lesion is very rare, these are considered as dystrophic calcification, dentinoid formation, ossification. The incidence of dystrophic calcification in recurrent OKC is low, so it can be inferred that the recurrence rate of OKC with dystrophic calcification is lower than that of conventional OKC.

Mucoepidermoid carcinoma (MEC) is the most common malignant epithelial tumor of the salivary gland in the oral cavity. In South Korea, it occurs most frequently in the palate, retromolar area, floor of the mouth, buccal mucosa, and other areas of the oral cavity. MEC is rare in children and adolescents under 20 years of age, but it is the most common malignant salivary gland tumor in this group. Reconstructive surgery is often required due to cystic lesions or resection of malignancy in the oral cavity. Buccal fat pad (BFP) is a flap that is reliable and suitable for reconstructing oral defects because it has a low complication rate and small volume change over time. Case Presentation: We report the case of a 12-year-old female patient with low-grade MEC on light soft palate with no neck metastasis. After tumor resection the palatal mucosal defect was reconstructed with a BFP flap. Conclusion: The purpose of this article is to discuss the features and treatment methods of MEC that is rarely occurring in children, and the usefulness of BFP for reconstruction. Therefore, we will make a precise diagnosis and treatment as we examine the clinical feature and review the literature.

Pseudosarcomatous fibromatosis (PSF), also known as nodular fasciitis and pseudosarcomatous fasciitis, is a rare, benign proliferation of fibroblasts and myofibroblasts. It is often misdiagnosed as sarcoma because of its characteristic rapid progression, leading to unnecessary and aggressive surgery. Here we report a case of PSF found in the masseter muscle in a 26-year-old female. The mass that could be misdiagnosed because of its rapid growth characteristics was surgically excised by an intraoral approach and diagnosed as PSF by histopathologic examinations.

It is well known that lymph node metastasis is a major prognostic factor in patients with oral squamous cell carcinoma (OSCC). 30-40% of patients with OSCC have already undergone regional metastasis at diagnosis. The survival rate of patients with metastasis is reduced by more than 50%. Therefore, prevention and early detection of metastasis are very important to increase the survival rate of patients. Many investigators have studied the molecular mechanism of metastasis and tried to develop the molecules to inhibit any step of metastatic cascade. Among those molecules, an interest in the metastasis suppressor gene has been increasing. Expression of metastasis suppressor KiSS-1 has shown to be significantly related to poor clinical outcome and worse survival rate of patient in various malignancies of different organs. In addition, our previous study in OSCC also revealed that downregulation of KiSS-1 expression correlated with the presence of cervical lymph node metastasis, one part of tumor progression. Therefore, further investigation was needed to identify the molecular function of KiSS-1 using OSCC cell line and to evaluate the possibility of KiSS-1 as a new therapeutic target.

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin's lymphoma, and usually showed painless neck swelling, fever, sweat, and weight loss. Although about 5% of all lymphomas appeared in the oral area, the primary maxillofacial lymphomas were rare and sometimes clinically tended to be misdiagnosed such as chronic periodontitis, osteomyelitits, etc. This study demonstrated three cases of primary DLBCL mimicking localized osteomyelitis at mandible or maxilla. A series of histological and immunohistochemical examination using different biomarkers of lymphoreticular cells were performed to characterize the neoplastic cells of DLBCL. The first case occurred in a 45 years old male exhibiting mandibular osteomyelitis and neck swelling. The second case simply showed a gingival swelling at left upper premolar area in a 55 years old male. And the third case is from an 84 years old female who felt numbness at left lower lip and had severe periodontitis involving regional alveolar bone resorption. All of three cases had experienced no systemic manifestation of lymphoreticular malignancy before the diagnosis of oral lymphoma. Immunostainings of CD3, CD20, TNFα, BCL-2, Ki-67, PCNA, and c-Myc were strongly positive in these tumor cells, while those of p53 and CD31 were slightly positive, and CD56 immunoreaction was negative. These three cases were diagnosed as DLBCL and referred to the hemato-oncology unit for treatment. Therefore, every chronic granulomatous periodontal lesion hardly cured by simple medical treatment should be carefully explored through pathological examination, and it was presumed that DLBCL is closely related to the chronic inflammatory periodontal lesions recruiting mucosa-associated lymphoid cells in older patients. It was also suggested that DLBCL be differentially diagnosed from T-cell lymphoma, Burkitt’s lymphoma, and Hodgkin’s disease, etc. with immunohistochemical determination of tumor cell subtypes as soon as possible in order to be treated with appropriate therapy.