Search

Oral giant cell fibromas (GCFs) are found predominantly in Caucasians and rarely in other races. This retrospective study evaluated the clinicopathological features of 24 GCFs in Taiwanese patients. Methods: Twenty-four consecutive cases of oral GCF were investigated from 1987 to 2008. Clinical data and microscopic features were reviewed and analyzed. Results: The mean age of patients at the time of diagnosis was 29 years. Oral GCF occurred more commonly in patients between 11 and 40 years of age. There were 12 male and 12 female patients. The lesions were found more frequently on the tongue (8 cases) and gingiva (7 cases). The mean size of the lesion was 5.5 mm (range, 2–10 mm) in greatest dimension. GCF is misdiagnosed frequently as fibroma (19 cases) or papilloma (5 cases). All tumors were treated by total surgical excision and no recurrence was found after treatment. Microscopically, the GCF was a sessile or pedunculated mass covered with a thin layer of parakeratinized or orthokeratinized stratified squamous epithelium. The tumor was composed mainly of loose or dense fibrous connective tissue with well-formed capillaries and no inflammation. The consistent and diagnostic feature was the presence of large stellate giant cells, usually with one or two nuclei. Multinucleated giant cells were seen occasionally. These giant cells were most numerous in the connective tissue just beneath the epithelium. Conclusion: Oral GCFs show no significant sex predilection and occur in patients in the second to fourth decades of life. Usually, the lesions are < 1 cm in diameter and are found more frequently on the tongue and gingiva. GCF resembles fibroma or papilloma and is difficult to diagnose correctly at the first glance. All GCFs can be treated by conservative surgical excision without subsequent recurrence.

Odontogenic keratocysts (OKCs) are more aggressive and more osteolytic lesions than dentigerous cysts (DCs) and radicular cysts (RCs). Osteopontin (OPN) is related to cancer metastasis and bone destruction. Binding of OPN to its cell membrane receptors integrin αv and CD44v6 can enhance tumor cell motility, migration, invasion and spread. This study assessed the possible contribution of OPN, integrin αv and CD44v6 to the local aggressive behavior and osteolytic ability of OKCs. Methods: We used an immunohistochemical method to examine the expression of OPN, integrin αv and CD44v6 in tissue sections of 20 OKCs, eight DCs and 10 RCs. Results: We found strong cytoplasmic OPN immunostaining in lining epithelial cells of 8 of 20 OKCs but not in any DCs and RCs. Positive OPN staining was also noted in the subepithelial connective tissue of four OKCs with intraepithelial expression of OPN. Diffuse and strong membranous integrin αv staining was discovered in osteoclasts in all our tissue sections and in nearly all lining epithelial cells of DCs and RCs, but not in OKCs. In addition, diffuse and strong membranous CD44v6 staining was also observed in nearly all lining epithelial cells of OKCs, DCs and RCs. Conclusion: Binding of OPN to osteoclast cell membrane receptor integrin αv can activate the osteoclasts and increase their osteolytic activity. In addition, binding of OPN to OKC lining epithelial cell membrane receptor CD44v6 can enhance the motility, migration, invasion and spread of lining epithelial cells into the surrounding cancellous bone. Therefore, we suggest that the local aggressive behavior and high osteolytic ability of OKCs in the jawbone can be explained at least partially by high expression of OPN and CD44v6 in lining epithelial cells of OKCs and high expression of integrin αv in osteoclasts.

Central ossifying fibroma (COF) is the most common benign fibro-osseous lesion of the jaw. This retrospective study evaluated the clinical and histopathologic features of 28 COFs in Taiwanese patients. Methods: Twenty-eight consecutive cases of COF were collected from 1988 to 2006. The clinical data and microscopic features of these cases were reviewed and analyzed. Results: The mean age of patients at the time of diagnosis was 34 years. There were six male and 22 female patients. Twenty-six (93%) cases were found in the mandible and two (7%) in the maxilla. The most common sites for COFs were the molar region (17 cases, 61%), followed by the premolar (8 cases, 28%), and incisor/canine (3 cases, 11%) regions. Bone swelling or expansion (96%, 26/27) was the most frequent clinical presentation. Six (21%) COFs presented as a radiolucent lesion, 17 (61%) as a mixed lesion, and five (18%) as a radio-opaque lesion. No recurrence of the lesion was found after surgical excision in this series. Microscopically, COFs showed trabeculae of woven bone (25 cases) and/or lamellar bone (5 cases) and/or spherules of cementoid (19 cases) in a cellular fibrous connective tissue stroma. The stromal component was highly cellular in 21 cases, moderately cellular in seven cases, prominently vascular in 11, and collagenous in six. Conclusion: COFs occur more frequently in female patients and in those in the second to fourth decades of life. The most commonly affected site is the mandible, especially the molar region. The majority of COF lesions present as a well-defined, mixed lesion radiographically. Most COFs can be treated by conservative surgical excision without subsequent recurrence.

Oral verruciform xanthoma (VX) is an uncommon oral mucosal lesion. This retrospective study evaluated the clinical and histopathologic features of 15 oral VXs occurring in Taiwanese patients. Methods: Fifteen consecutive cases of oral VX were collected from January 1988 to December 2005. Clinical data and microscopic features of these cases were reviewed and analyzed. Results: The mean age of patients was 45 years (range, 18-79 years). There were eight male and seven female patients. Seven (46.6%) cases occurred on the gingiva, four (26.7%) on the tongue, and four (26.7%) on the buccal or vestibular mucosa. The greatest mean dimension of the lesions was 0.8 cm (range, 0.3-2.0 cm). Three patients had concomitant other oral mucosal lesions such as oral submucous fibrosis, squamous cell carcinoma, and erosive oral lichen planus. Microscopically, all specimens showed varying degrees of surface parakeratosis and the accumulation of numerous foam cells in the connective tissue papillae among uniformly elongated epithelial ridges. Individuals or aggregates of foam cells were also found underneath the epithelial ridges in nine (60%) cases. When the oral VX lesions were further classified into three types according to the microscopic surface architecture, seven (47%) lesions were of the verrucous type, three (20%) the papillary type, and five (33%) the flat type. All patients received surgical excision of the lesions and no recurrence was noted during follow-up of up to 18 years. Conclusion: Oral VXs occur more frequently in the fifth decade of life. The more commonly affected site is the gingiva. The treatment of choice for oral VXs is surgical excision. The prognosis is excellent and recurrence was not seen in this study. [J Formos Med Assoc 2007;106(2):141-147]

Erythropoietin (Epo) is a multi-functional growth factor that promotes cell proliferation, migration and survival, tumor angiogenesis, and tumor cell invasion and metastasis. Its diverse biological effects are mediated through its interaction with its erythropoietin receptor (EpoR). In this study, we examined the expression of Epo and EpoR in 60 specimens of oral squamous cell carcinoma (OSCC), 40 specimens of oral epithelial dysplasia (OED), 20 specimens of oral epithelial hyperkeratosis (OEH), and 10 specimens of normal oral mucosa (NOM) by immunohistochemistry. The Epo and EpoR labeling indices (LIs) in OSCC, OED, OEH, and NOM groups were calculated and compared between groups. The correlation between the expression of Epo or EpoR in OSCCs and clinicopathological parameters or survival of OSCC patients was analyzed statistically to investigate the possible influence of Epo or EpoR on the progression and prognosis of OSCCs in Taiwan. Positive Epo or EpoR staining was mainly cytoplasmic. The mean Epo LI increased significantly from NOM (0%) through OEH (14±10%) and OED (45 ±24%) to OSCC samples (68±21%, p = 0.000). The mean EpoR LI also increased significantly from NOM (8±3%) and OEH (30±13%) through OED (53 ±27%) to OSCC samples (74 ±23%, p = 0.000). Statistical analysis showed a significant association of higher Epo or EpOR expression in OSCCs with the younger age of patients, the larger tumor size, the presence of lymph node metastases, and the more advanced clinical stages of OSCC. Our results suggest that the expression of Epo and EpoR is an early event in oral carcinogenesis in Taiwan. The Epo or EpoR LI in OSCC samples can predict the progression of OSCCs in Taiwan. [ABSTRACT FROM AUTHOR]

Peripheral ossifying fibromas (POFs) present as tumor-like growths on the gingiva or alveolar mucosa. They are often misdiagnosed as a fibrous epulis, a pyogenic granuloma, or a peripheral giant cell granuloma. Data on 27 patients each with a POF diagnosed and treated in our institute during the period from 1988 to 2006 were analyzed in this study. There were 16 female and 11 male patients. The mean age of the 27 patients at the time of diagnosis was 38 years. The sizes of the 27 POFs ranged from 5 to 30 mm in greatest dimension with an average size of 15 mm. Clinically, they usually presented as reddish, firm, pedunculated, or sessile masses on the gingiva or alveolar mucosa. The overlying mucosa was either completely intact (13 cases) or focally ulcerated (14 cases). The more-common sites for POF lesions were the premolar and molar regions of the maxilla (52%). All patients ultimately received total surgical excision of the lesion. Of the 27 POFs, 4 (15%) experienced a single recurrence. Histologically, the POFs showed trabeculae or islands of mineralized products in a cellular fibrous connective tissue stroma. The mineralized products were defined as woven bone (22 cases), lamellar bone (6 cases), cementoid (12 cases), or amorphous material of dystrophic calcification (4 cases). We concluded that POFs occur more commonly in female patients aged < 50 years. The more-common sites for POFs were the premolar and molar regions of the maxilla in this series. The recurrence rate for our POF lesions was 15%. [ABSTRACT FROM AUTHOR]

Overexpression of metastasis-associated protein 1 (MTA1) has been demonstrated in a variety of human cancers and found to be significantly associated with the tumor size, lymph node metastasis, clinical stage, tumor invasion, and prognosis of these cancers. In this study, we examined the expression of MTA1 in 74 specimens of oral squamous cell carcinoma (OSCC), 100 specimens of oral epithelial dysplasia (OED; 33 mild, 44 moderate, and 23 severe OED cases), and 21 specimens of normal oral mucosa (NOM) by immunohistochemistry. The cytoplasmic and nuclear MTA1 labeling indices (LIs) in OSCC, OED, and NOM samples were calculated and compared among these groups. Correlations of the cytoplasmic and nuclear MTA1 Us in OSCC with clinicopathological parameters and survival of OSCC patients were statistically analyzed. We found that the mean cytoplasmic MTA1 Us were all over 95% for the NOM, OED, and OSCC samples. There were no significant associations of the cytoplasmic MTA1 LI with any of the clinicopathological parameters of OSCC patients. The mean nuclear MTA1 LIs significantly decreased from NOM (73% ± 13%) to mild OED (71% ± 16%), moderate OED (60% ± 22%), and severe OED (46% ± 25%) and OSCC samples (30% ± 30%, p < 0.001). A significant correlation was found between the lower mean nuclear MTA1 LIs and OSCCs located on the buccal mucosa and tongue (p = 0.001), with larger tumor sizes (T3 and T4, p = 0.020), with regional lymph node metastases (Ni, N2, and N3, p = 0.024), and with more-advanced clinical stages (stages 3 and 4, p = 0.045). Our results suggest that MTA1 is universally expressed in the cytoplasm of normal, dysplastic, and malignant oral epithelial cells. The nuclear expression of MTA1 significantly dropped from NOM through OED to OSCC samples, and was inversely related to the T status, N status, and clinical staging of OSCCs. Therefore, the nuclear MTA1 LI can be used to predict the progression of OSCCs in Taiwan. [ABSTRACT FROM AUTHOR]

Background: Bone morphogenic proteins (BMPs) are important bone-induction factors, and the development of a suitable carrier for BMPs is a critical step to achieve osteoinductive function. The aims of the present study were to evaluate, at the cellular and molecular levels, the feasibility of recombinant human BMP-2 (rhBMP-2)--collagen composite scaffold and its efficiency for carrying BMP-2 in ectopic bone formation in rats. Methods: Scaffolds with (test) or without rhBMP-2 (control) were made and implanted into the calf muscle of 16 5-week-old rats. The tissue responses to the scaffolds were examined by histology. Masson's trichrome and von Kossa stainings were performed to examine collagen matrix deposition and calcification at 3, 7, 10, and 14 days. Expressions of bone phenotypic markers, alkaline phosphatase, osteocalcin, osteopontin, and bone sialoprotein were detected by reverse transcription polymerase chain reaction and immunohistochemistry. Results: No detectable adverse responses were noted around the implanted scaffolds, and the area of the resorbed scaffold had been replaced by young connective tissue by 3 to 7 days in both groups. In the rhBMP 2 composite scaffold, collagen matrix deposition was found in the implanted site on day 7 and initial signs of endochondral differentiation also appeared. Mineralization and the expressions of key bone proteins were demonstrated in chondroblasts and osteoblasts at 7 to 14 days. Molecular cascades of bone induction were not shown in control specimens. Conclusion: The rhBMP 2-atelocollagen scaffold showed excellent biocompatibility and possessed a bone inducing capacity in rat within 2 weeks, and, thus, may provide a potential application in tissue engineering of bone tissue. J Periodontol 2007; 78:335-343. [ABSTRACT FROM AUTHOR]

Oral malignant melanomas (OMMs) are a rare entity that account for only 0.5% of all oral malignancies. Regional lymph node metastasis rarely develops without recurrence at the primary site which had received wide excision. This report presents a case of an OMM occurring at the anterior maxillary labial and palatal gingivae in a 63-year-old female patient. The primary tumor received wide surgical excision. However, submandibular and cervical lymph node metastases developed 7 months later without primary site recurrence. The metastatic lymph nodes were removed by a modified radical neck dissection. The histopathological examination of the primary tumor and metastatic nodes showed a sheet of non-pigmented proliferating epithelioid cells with vesicular nuclei and prominent nucleoli. Melanin-laden macrophages and multinucleated foreign body giant cells were also found scattered within the sheet of non-pigmented tumor cells. Immunohistochemical studies demonstrated that the non- pigmented tumor cells were negative for cytokeratin, strongly positive for HMB-45 and neuron-specific enolase (NSE), moderately positive for MART-1/Melan-A, and weakly positive for S-100 protein and Mitf, suggestive of a malignant melanoma. Anti-CD68 immunostaining revealed positive cytoplasmic staining in the melanin-laden macrophages and multinucleated foreign body giant cells. Tumor cell invasion into the alveolar process of the maxilla was also evident. Because 2 of 27 left submandibular and cervical lymph nodes revealed metastatic melanoma with extracapsular spread, the patient was further arranged for chemotherapy to control the progression of the disease. The patient is still under close follow-up in the clinic of the Oral and Maxillofacial Surgery Department at our hospital, and no tumor recurrence at the operated primary site or neck area has been found so far. [ABSTRACT FROM AUTHOR]

Oral submucous fibrosis (OSF) is a precancerous condition. This point of view is supported by a high frequency of oral epithelial dysplasia, oral leukoplakia, and oral squamous cell carcinoma (OSCC) found in patients with OSF. In this study, we used an immunohistochemical technique to study the expression of cytokeratin 13 (CK13) in 16 specimens of normal buccal epithelium, 8 specimens of the epithelium covering an oral fibroma, 16 specimens of oral epithelial hyperplasia, 13 specimens of oral epithelial dysplasia, 25 specimens of the epithelium adjacent to an OSCC, 47 specimens of OSF epithelium, and 28 specimens of OSCC. We found 3 distinct patterns of CK13 expression in these specimens. The first group of specimens including the normal buccal epithelium, epithelium covering an oral fibroma, oral hyperplastic epithelium, and mildly dysplastic oral epithelium uniformly showed grade 5 (positive cells > 80% of all epithelial cells) CK13 expression. The second group of specimens including OSF epithelium and the epithelium adjacent to an OSCC demonstrated a great variation in CK13 expression with approximately 1/3 of specimens showing grade 5 CK13 expression and 2/3 showing marked attenuation of CK13 expression. The third group of specimens including moderately and severely dysplastic oral epithelium and malignant epithelium of an OSCC also exhibited a great variation in CK13 expression with more than 95% showing a marked decrease in CK13 expression. Because mild to severe dysplasia is frequently found in the epithelium adjacent to an OSCC and the CK13 expression pattern in OSF epithelium is similar to that in dysplastic oral epithelium and to that in the epithelium adjacent to an OSCC, we suggest that OSF may be a premalignant lesion. [ABSTRACT FROM AUTHOR]

Five cases of oral malignant fibrous histiocytoma (MFH) in patients who had previously received radiotherapy in the head or neck region were included in this study. There were 3 men and 2 women. Four patients had been irradiated for nasopharyngeal carcinoma (NPC) and the other for a squamous cell carcinoma (SCC) involving the tongue and mouth floor. The MFH developed 2.5-11 years after the initial radiotherapy. Two cases of MFH occurred in the maxilla, two in the mandible, and the remaining one in the tongue, floor of mouth and mandible. Clinically, the oral post-radiation MFH presented as tender, reddish, elastic, lobulated masses with surface ulceration. Radiographic examination of the involved jaws revealed a poorly defined radiolucent lesion without any periosteal or endosteal reaction. The prognosis of these tumors was very poor. Although aggressive multimodality treatment had been applied, 3 of 5 patients eventually died of the disease, with a mean survival time of 17 months after establishing the diagnosis of MFH. In order to ensure the early diagnosis and treatment of this radiation-induced second malignancy, close oral follow-up is mandatory for patients who have received radiotherapy for head and neck malignancies. [ABSTRACT FROM AUTHOR]