Accelerated biodegradation of silk sutures through matrix metalloproteinase activation by incorporating 4-hexylresorcinol.

Silk suture material is primarily composed of silk fibroin and regarded as a non-resorbable material. It is slowly degraded by proteolysis when it is implanted into the body. 4-Hexylresorcinol (4HR) is a well-known antiseptic. In this study, the biodegradability of 4HR-incorporated silk sutures were compared to that of untreated silk sutures and polyglactin 910 sutures, a commercially available resorbable suture. 4HR-incorporated silk sutures exhibited anti-microbial properties. Matrix metalloproteinase (MMP) can digest a wide spectrum of proteins. 4HR increased MMP-2, -3, and -9 expression in RAW264.7 cells. MMP-2, -3, and -9 were able to digest not only silk fibroin but also silk sutures. Consequently, 59.5% of the 4HR-incorporated silk suture material remained at 11 weeks after grafting, which was similar to that of polyglactin 910 degradation (56.4% remained). The residual amount of bare silk suture material at 11 weeks after grafting was 91.5%. The expression levels of MMP-2, -3 and -9 were high in the 4HR-incorporated silk suture-implanted site 12 weeks after implantation. In conclusion, 4HR-treated silk sutures exhibited anti-microbial properties and a similar level of bio-degradation to polyglactin 910 sutures and induced higher expression of MMP-2, -3, and -9 in macrophages.

Atypical granular cell tumor in the maxilla: The first report of primary intraosseous granular cell tumor.

BACKGROUND: Granular cell tumor (GCT) is a benign soft tissue tumor of neural origin and is characterized by eosinophilic granular cells showing positivity for neuronal markers. Herein, we report the first case of primary intraosseous GCT arising in the maxilla of an adolescent girl. METHODS AND RESULTS: A 16-year-old female patient presented with palatal swelling. Radiographic findings revealed a well-defined radiolucent lesion centrally located in the right maxilla. Mass excision was performed, and histopathologic examination showed sheets and cords of eosinophilic granular cells with cellular pleomorphism. Tumor cells were strongly positive for vimentin, S-100 protein, and CD56, and negative for cytokeratin, desmin, smooth muscle actin, and c-kit. High expression of p53 and Ki-67 was found. The final diagnosis was atypical GCT. CONCLUSION: When evaluating an intraosseous radiolucent lesion with histopathologic features of granular cells, clinicians and pathologists should include GCT in the differential diagnosis. © 2016 Wiley Periodicals, Inc. Head Neck 38:E2467-E2470, 2016.

Prognostic significance of nestin in primary malignant melanoma of the oral cavity.

Several studies have examined the correlation between nestin expression and the degree of tumor invasion in cutaneous melanoma. However, no information has been reported on nestin in primary mucosal melanoma of the head and neck. The present study examined the expression and prognostic significance of nestin in patients with primary mucosal melanoma of the oral cavity. Nestin expression was examined immunohistochemically in 39 patients (six oral melanoma in-situ cases and 33 invasive oral melanoma cases) and analyzed for association with disease progression. Age, sex, anatomic site, stage, level of invasion, regional lymph node metastasis, surgical margin involvement, and treatment modality were also analyzed. In the 33 invasive melanoma cases, invasion depth correlated significantly with prognosis in univariate and multivariate analyses. High-intensity nestin staining was observed in 14 of the 33 cases and a high proportion of nestin-positive cells was observed in 16 cases. In stage III oral melanoma cases, nestin expression was not significantly associated with disease progression. However, in stage IV cases, both the intensity and the proportion of nestin expression were significantly associated with disease progression (P=0.022 and 0.005, respectively). In all 33 invasive cases, multivariate analyses showed that both the intensity and the proportion of nestin were significantly associated with a poor prognosis (P=0.014 and 0.009; hazard ratio, 3.59 and 4.05; 95% confidence interval, 1.29-9.98 and 1.42-11.56, respectively). In conclusion, nestin can be a valuable prognostic indicator in the advanced-stage (stage IV) cases of oral mucosal melanoma.

Staging significance of bone invasion in small-sized (4cm or less) oral squamous cell carcinoma as defined by the American Joint Committee on Cancer.

OBJECTIVES: The staging significance of bone invasion is controversial in oral squamous cell carcinoma (OSCC) cases with tumors measuring 4cm or less according to the American Joint Committee on Cancer (AJCC). Our aim was to retrospectively examine a large group of patients with OSCC to determine the staging significance of bone invasion. MATERIALS AND METHODS: Three hundred and twenty-three patients with primary OSCC were classified based on tumor size. Bone invasion was categorized as absent, one side bone, and both buccal and lingual bones, and analyzed for association with disease progression. Regional lymph node metastasis (N), perineural invasion, vascular invasion, surgical margin involvement, and adjuvant treatment were also analyzed. RESULTS: In all OSCC cases, bone invasion (p=0.007) with stage N, perineural invasion, and surgical margin involvement were significant independent prognostic factors of disease progression. However, in OSCC cases with tumors measuring 4cm or less, bone invasion was not significantly associated with disease progression. Nevertheless, invasion of both buccal and lingual bones was significantly associated with disease progression (p=0.03). In multivariate analysis, both buccal and lingual bone invasion (p=0.04; hazard ratio=3.4; 95% confidence interval, 1.0-11.0), stage N2, and perineural invasion were also independent prognostic factors. CONCLUSION: Although OSCC bone invasion was an independent prognostic factor, bone invasion in small OSCC was not. However, small OSCC with both buccal and lingual bone invasion had a significantly worse prognosis. The AJCC T system is of limited prognostic value for small OSCC with bone invasion. But other elements should be examined before a modification can be accepted.

KiSS-1 expression in oral squamous cell carcinoma and its prognostic significance.

Downregulated expression of KiSS-1 has been correlated with tumor progression, metastasis, and patient prognosis in various human malignancies. However, there is no information regarding the expression of KiSS-1 in oral squamous cell carcinoma (OSCC). Our aims were to examine KiSS-1 expression in OSCC tissue samples and cell lines and to determine its prognostic significance. KiSS-1 expression was significantly lower in lymph node (LN) metastases than in primary tumor tissues. Five of six OSCC cell lines showed absence or relatively low expression of KiSS-1. Correlations between KiSS-1 expression and clinicopathological parameters were statistically assessed. There were significant correlations between KiSS-1 expression and LN metastasis (p = 0.007), TNM stage (p = 0.024), and local recurrence (p = 0.012). In the Kaplan-Meier survival analysis, negative KiSS-1 expression significantly correlated with poorer overall survival (OS) and disease-free survival (DFS) (p = 0.000 and 0.000, respectively). Multivariate analysis using Cox regression modeling revealed that KiSS-1 expression was an independent prognostic factor for both OS and DFS (p = 0.001 and 0.000, respectively). Our findings suggested that KiSS-1 downregulation may play a role in tumor progression and metastasis of OSCC and may be a reliable biomarker for predicting clinical outcome in OSCC.

Geriatric oral lesions: A multicentric study.

AIM: To carry out an oral biopsy survey in geriatric patients from the participating institutions. METHODS: The biopsy records of the participating institutions were reviewed for oral lesions from patients aged 65 years and older diagnosed from 2003 to 2012. Demographic data and the site of the lesions were collected. Histopathological diagnoses were categorized into two categories: non-neoplastic lesions (reactive/inflammatory lesion, cyst, allergic/immunologic disorders, potentially malignant disorders, infection and others) and neoplastic lesions (benign and malignant tumors). Data were analyzed by appropriate statistics using stata11. RESULTS: Of the 76,045 accessioned cases, 11,346 cases (14.92%) were in geriatric patients. The mean age of the patients was 72.98 ± 6.25 years. A total of 5010 cases (44.16%) were diagnosed in males, whereas 6336 cases (55.84%) were diagnosed in females. The male-to-female ratio was 0.79:1. Non-neoplastic lesions outnumbered the neoplastic counterpart. The five most prevalent oral lesions in the geriatric population in the present study in descending order of frequency were squamous cell carcinoma, focal fibrous hyperplasia (irritation fibroma), radicular cyst, osteomyelitis and epithelial dysplasia, respectively. The site of predilection was labial/buccal mucosa, followed by gingiva, mandibular bone, tongue and maxillary bone, respectively. CONCLUSIONS: The geriatric oral lesions from the present study showed a similar trend with studies based on histopathological data, but different from the studies based on clinical data. This study also shed more light on potentially malignant disorders, as well as benign and malignant tumors.

Thymosin ß4 induces proliferation, invasion, and epithelial-to-mesenchymal transition of oral squamous cell carcinoma.

The epithelial-to-mesenchymal transition (EMT) plays a vital role in carcinogenesis, invasion, and metastasis of many epithelial tumors including oral squamous cell carcinoma (OSCC), a common malignancy of the head and neck. However, the functional role of the actin-sequestering protein thymosin ß4 (Tß4) in the EMT in OSCCs remains unclear. Thus, we investigated whether overexpression of Tß4 could induce in vitro tumorigenesis such as cell proliferation and anchorage independency and an EMT-like phenotype in OSCCs. Also, we examined whether it affects invasiveness and cell motility-associated signaling molecules. Tß4-overexpressing OSCCs, SCC-15_Tß4 and SCC-25_Tß4, enhanced cell proliferation and colony formation. In addition, we observed that Tß4 overexpression induced an EMT-like phenotype, accompanied by a decrease in expression of the epithelial cell marker E-cadherin and an increase in expression of mesenchymal cell markers vimentin and N-cadherin. Also, the expression level of Twist1, an EMT-inducing transcription factor, was significantly enhanced in SCC-15_Tß4 and SCC-25_Tß4 cells. Tß4 overexpression augmented in vitro invasion and MMP-2 activity and enhanced the phosphorylation of paxillin and cortactin and expression of LIMK1. Taken together, these results suggest that Tß4 overexpression could be one of the causes of tumorigenesis and progression in OSCCs. Further investigation on the Tß4 molecule would encourage the development of specific targets for cancer treatment.

Chondrosarcoma of the temporomandibular joint: a case report and review of the literature.

OBJECTIVE: Chondrosarcoma is the second most common sarcoma arising in the bone, but it rarely involves the temporomandibular joint (TMJ). To date, 30 cases of TMJ chondrosarcoma have been reported in the English literature, and the authors report an additional case arising from a cystic lesion in a 60-year-old female patient. CLINICAL PRESENTATION: The clinical and radiological diagnosis of the lesion was initially synovial cyst, and periodic check-ups were done after aspiration of the lesion. After three years, the patient perceived swelling of the lesion, and surgical excision was performed. The final diagnosis was grade I chondrosarcoma. CONCLUSION: When clinicians detect a cystic lesion in the radiographic imaging of the TMJ, chondrosarcoma should be included in the differential diagnosis. In addition, computed tomography (CT) as well as magnetic resonance imaging (MRI) is recommended for the accurate diagnosis and proper preoperative planning in TMJ chondrosarcoma.

The Effect of a Combination of Implant Controller and Handpiece from Different Manufacturers on the Torque Value.

PURPOSE: To determine the accuracy of applied torque of different implant controller and handpiece combinations by using an electronic torque gauge. MATERIALS AND METHODS: Four combinations of the following devices were tested: Surgic XT controller (NSK), XIP10 controller (Saeshin), X-SG20L handpiece (NSK), CRB26LX handpiece (Saeshin). For five torque settings, 30 measurements were recorded at 30 revolutions per minute by using an electronic torque gauge fixed to jigs, and means were calculated. RESULTS: Applied torques were generally higher than the set torque of 10 and 20 Ncm and lower than the set values of 40 and 50 Ncm. The average torque deviations differed significantly among the combinations (P < .05). At 10 and 20 Ncm, the Surgic XT/X-SG20L combination yielded the closest value to the intended torque, followed by the XIP10/X-SG20L combination. At 30 Ncm, the XIP10/X-SG20L combination showed the nearest value. At 40 Ncm, the Surgic XT/X-SG20L, XIP10/CRB26LX, and XIP10/X-SG20L combinations showed deviations within 10%. At 50 Ncm, all the combinations showed lower applied torque than the set value. Large standard deviations were observed in the Surgic XT/CRB26LX (13.288) and Surgic XT/X-SG20L (7.858) combinations. CONCLUSION: Different combinations of implant controllers and handpieces do not generate significant variations in applied torque. The actual torque varies according to the torque setting. It is necessary to calibrate devices before use to reduce potentially problematic torque.

The potential of interleukin 12 receptor beta 2 (IL12RB2) and tumor necrosis factor receptor superfamily member 8 (TNFRSF8) gene as diagnostic biomarkers of oral lichen planus (OLP).

OBJECTIVE: This study evaluated the potential of interleukin 12 receptor beta 2 and tumor necrosis factor receptor superfamily member 8 as diagnostic biomarkers of oral lichen planus (OLP). MATERIALS AND METHODS: The mRNA expression of IL12RB2 and TNFRSF8 in FFPE OLP samples (OLP group, n = 38) were investigated with quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis and compared to those of chronic non-specific mucositis (Non-OLP group, n = 25) and normal mucosa (Normal group, n = 18). Predictive modeling of the expression of IL12RB2 and TNFRSF8 was constructed using support vector machine (SVM), random forest (RF), linear discriminant analysis (LDA), neural network (NN) and naive Bayes (NB) methods. RESULTS: Normalized expression of IL12RB2 in the OLP group (3.78 ± 1.67) was significantly higher than the Normal group (1.97 ± 1.12), but lower than the Non-OLP group (6.86 ± 1.67). TNFRSF8 gene expression in the OLP group (7.46 ± 1.51) was significantly higher than the Normal group (2.90 ± 1.61), but no significant difference was found between the OLP and Non-OLP groups. The ratio of IL12RB2/TNFRSF8 in the OLP group (0.52 ± 0.23) was significantly lower than the Normal group (0.74 ± 0.39) and the Non-OLP group (1.07 ± 0.38). In the predictive modeling, the area under receiver operating characteristic (ROC) curves (AUC) ranged from 0.83-0.92 and their accuracy was higher than 0.75 in all methods. CONCLUSIONS: The IL12RB2/TNFRSF8 ratio can be a useful diagnostic tool for OLP.

The role of p300 in the tumor progression of oral squamous cell carcinoma.

BACKGROUND: EP300 gene encoding p300 is a candidate tumor suppressor gene. This study investigated p300 expression and gene alteration in oral squamous cell carcinoma (OSCC) specimens to assess its role in OSCC development. METHODS: Genomic DNA extracted from 13 human OSCC cell lines and 40 OSCC patient specimens was subjected to methylation-specific PCR and exon sequencing. Immunohistochemical staining with primary antibodies against p300 and p53 was performed in 48 patients with OSCC. We analyzed the association between the data and clinicopathological factors of OSCC patients. RESULTS: Methylation-specific PCR revealed that the EP300 promoter region was not hypermethylated in OSCC. Only one cell line demonstrated a point mutation at exon 31. On immunohistochemical examination, patients with metastatic lymph nodes (P = 0.009) and advanced clinical stage (P = 0.046) tended to show increased expression of p300. There was no statistically significant relationship between p300 expression and p53 accumulation in OSCC tissue samples. Patient survival was not correlated with p300 expression. CONCLUSIONS: EP300 is not a tumor suppressor gene because there was neither epigenetic inactivation of the gene nor a mutation resulting in functional impairment. Based on p300 overexpression and its association with clinical factors in patients with OSCC, it is likely that p300 itself or one of its target genes plays a key role in the aggressive phenotypes of OSCC.

Plasmablastic lymphoma of the oral cavity in a human immunodeficiency virus-negative patient: a case report with literature review.

Plasmablastic lymphoma (PBL) is an aggressive diffuse large B-cell lymphoma variant that is most frequently observed in the oral cavity of human immunodeficiency virus (HIV)-infected individuals. However, in recent years, some cases have emerged in patients without HIV infection and involve other sites like stomach, lung, nasal cavity, and jejunum. We report a rare case of PBL in the maxillary anterior area of a 62-year-old man without HIV infection. The tumor cells were characterized by non-cohesive round or oval shape cells with eccentrically-placed nuclei with a prominent perinuclear halo. Immunohistochemical studies showed that the tumor cells were strongly positive for MUM1, VS38c, VMT, and κ light chain, focally positive for LCA and CD79a, and negative for CD3, CD20, CD56, λ light chain, CK-pan, EMA, and HMB45. The patient was treated with chemotherapy using cyclophosphamide, doxorubicin, vincristine, and prednisone. The lesion showed partial remission.

Hypothetical pathogenesis of eosinophilic infiltration in Langerhans cell histiocytosis of the jaw.

OBJECTIVE: The present study investigated the densities of mast cells and CCL-11/eotaxin-1 expression of tumor cells in Langerhans cell histiocytosis (LCH) of the jaw. STUDY DESIGN: Eleven LCH cases arising in the jaws were selected. We evaluated eotaxin-1 expression in LCH cells via immunohistochemical staining. Toluidine blue was used to stain mast cells, with 20 periapical granuloma specimens serving as the control group. RESULTS: In all 7 patients with multifocal LCH, jaw lesions were the earliest manifestation. Toluidine blue staining revealed that most of the mast cells involved in LCH were degranulated, and the number of mast cells in LCH lesions was not significantly higher than in periapical granulomas. Upon immunohistochemical examination, all patients but one showed positivity for eotaxin-1 in LCH cells. CONCLUSION: This preliminary study suggests that eotaxin-1 expression in LCH cells may contribute to eosinophilic infiltration. Further studies of chemokine-receptor interactions will be needed to confirm this.

A giant radiopaque mass in the masticatory space.

A 2-year-old boy presented with a giant mass in the masticatory space. The mass exhibited a lobulating ossification, with no attachment to the adjacent normal bone. An enucleation was performed under the tentative diagnosis of extra-articular synovial chondromatosis, benign ossifying neoplasm, non-neoplastic heterotopic ossification, or low-grade malignancy. Upon microscopic examination, the excised mass was composed of multiple osteocartilaginous areas. We hereby present detailed clinicopathological findings.

Histopathological features of bisphosphonate-associated osteonecrosis: findings in patients treated with partial mandibulectomies.

The present study investigated the histopathologic and radiographic features of stage 3 bisphosphonate-associated osteonecrosis of the jaw (BAONJ) in patients who were treated with partial mandibulectomies. Bisphosphonates had been orally administered to 10 patients with osteoporosis and intravenously administered to 1 patient with metastatic carcinoma. On radiographic images, massive osteolysis and periosteal bone formations were conspicuous, and a thin mandibular cortical width was observed in 5 of 10 osteoporosis patients despite the previous use of bisphosphonate. Microscopically, the mandibulectomy specimens of the patients could be divided into 4 distinct layers. Although there were few differences in overall histologic features between BAONJ and chronic suppurative osteomyelitis, a notable number of osteoclasts were found detached from the bony trabeculae in BAONJ.

Comparative immunohistochemical study of ameloblastoma and ameloblastic carcinoma.

OBJECTIVE: Ameloblastic carcinoma combines the histologic features of ameloblastoma with cytologic atypia, regardless of whether it has metastasized. Because of its rarity, there are few immunoprofile studies of ameloblastic carcinoma and few comparative studies of ameloblastic carcinoma and ameloblastoma. In this study, we compared the expression levels of cytokeratins (CKs), matrix metalloproteinases (MMPs), and Ki-67 between ameloblastoma and ameloblastic carcinoma, and assessed the usefulness of these markers for differentiating the tumors. STUDY DESIGN: We assessed CK7, CK14, CK18, CK19, MMP-2, MMP-9, and Ki-67 expression by immunohistochemistry in 10 cases of ameloblastoma and 7 cases of ameloblastic carcinoma and then compared expression patterns between the 2 groups. RESULTS: Immunostaining for CK14 and CK19 was diffuse and strongly positive in both tumor types, but staining for CK7 was focally positive in only 1 case of ameloblastoma and absent in all cases of ameloblastic carcinoma. However, there was a significant difference in CK18 expression between the 2 tumors (P = .000). Whereas 80% of ameloblastomas showed negative reactivity for CK18, most cases of ameloblastic carcinomas showed a moderate to strong intensity of immunostaining for CK18. Regarding the expression of MMPs, there were significant differences in parenchymal MMP-2 and stromal MMP-9 expression between the 2 tumors. Compared to ameloblastoma, ameloblastic carcinoma showed significantly strong expression of MMP-2 in parenchymal cells (P = .001) and MMP-9 in stromal cells (P = .013). However, there were no differences in MMP-2 expression of stromal cells and MMP-9 expression of parenchymal cells between ameloblastoma and ameloblastic carcinoma. The mean Ki-67 labeling index (LI) of ameloblastic carcinomas was 17.21%, which was significantly higher than that of ameloblastomas (3.57%; P = .002). CONCLUSIONS: The significant expression of CK18, parenchymal MMP-2, stromal MMP-9, and Ki-67 could provide useful markers for differentiating ameloblastic carcinoma from ameloblastoma.

Relationship between the expressions of PD-L1 and tumor-infiltrating lymphocytes in oral squamous cell carcinoma.

Tumor-infiltrating lymphocytes (TILs) are considered to represent immune reactions of the host to a malignant tumor. Programmed death receptor ligand-1 (PD-L1) is a surface protein that blocks the function of T lymphocytes and is expressed on cancer cells. Tumor-associated fibroblasts (TAFs), which influence tumor growth have also been reported to express PD-L1 and thus inhibit TILs. In the present study, we investigated the densities of CD4(+)/CD8(+) TILs, PD-L1 expression of tumor cells and TAFs in oral squamous cell carcinoma (OSCC). Forty-five cases of OSCC were selected. We evaluated PD-L1 expression and the infiltration degree of each lymphocyte by immunohistochemical examination. These data were analyzed in connection with clinicopathological factors. Peritumoral CD8(+) TILs were observed in every patient with OSCC, and their densities were correlated with lymph node metastasis (P<0.001), tumor size (P=0.003), and clinical stage (P<0.001). PD-L1 expression on OSCC cells was observed in 39 cases and was associated with the lower density of intratumoral CD8(+) TILs (P=0.047). PD-L1 expression of tumors <4cm in size was correlated with the histological grade of the tumor (P=0.022). TAFs were positive for PD-L1 in 18 cases. Peritumoral TILs were significantly associated with tumor size, lymph node metastasis and clinical stage. Though PD-L1 expressed by OSCC cells did not affect patients' survival, its correlation with decreased number of intratumoral TILs suggests that the development of a strategy to block the interactions of PD-L1 with TIL would be a useful tool for inhibiting tumor growth.

The role of Cripto-1 in the tumorigenesis and progression of oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC), the most common malignancy of the oral cavity, remains a lethal disease in over 50% of cases diagnosed annually, due mostly to late detection of this cancer in its advanced stages despite the easy accessibility of the oral cavity for regular examinations. Cripto-1 is a member of the epidermal growth factor (EGF)-CFC protein family and is involved in the activation of several different signaling pathways during embryonic development and cellular transformation. Although the Cripto-1 protein is overexpressed in several human cancers including breast, colon, cervix, gastric, and pancreatic cancer, no prior study has evaluated Cripto-1 expression in OSCC. Therefore, our aims in this study were to examine Cripto-1 expression in clinical samples of OSCC patients using immunohistochemistry, to analyze the correlation between Cripto-1 expression and clinicopathologic parameters, and to identify the oncogenic roles of Cripto-1 in OSCC cell lines. Both epithelial dysplasia (73.3%) and OSCC (55.5%) tissue samples showed significantly higher expression of Cripto-1 than normal mucosa (20%) (p=0.031). In the OSCC samples, there was a significant correlation between Cripto-1 expression and the histological differentiation of OSCC (p=0.015) and a high PCNA index (p=0.011). The in vitro cell proliferation assays demonstrated that recombinant human Cripto-1 (rhCripto-1) induced both SCC-4 and SCC-25 cells to proliferate as compared with control cells (p<0.05 and p<0.01, respectively). In in vitro migration assays, treatment of SCC-4 and SCC-25 cells with rhCripto-1 protein induced a 2.4-fold and 1.7-fold-increase in cell migration, respectively (p=0.000 and p=0.008, respectively). Taken together, our data suggest that Cripto-1 plays a role in the malignant transformation of the oral mucosa and is involved in the tumorigenesis and progression of OSCC by promoting the growth and migration of malignant cells.

Recurrent odontogenic ghost cell carcinoma (OGCC) at a reconstructedfibular flap: A case report with immunohistochemical findings

Odontogenic ghost cell carcinoma (OGCC), a malignant counterpart of the odontogenic ghost cell tumor (OGCT),with aggressive growth characteristics, is exceedingly rare. A painful swelling in the jaw with local paresthesia isthe most common symptom.We described a case of 47-year Korean woman who had a rare central epithelial odontogenic ghost cell carcinomawhich recurred at reconstructed fibular flap. Immunohistochemical differences between OGCT and OGCC analyzedusing primary and recurred surgical specimen. On the basis of this case, the tumor started as an OGCT andtransformed into OGCC with highly aggressive, rapidly growing, infiltrative tumors. Our findings suggest thatsome of the cytokines produced by ghost cells may play important roles in causing extensive bone resorption inthe odontogenic ghost cell carcinoma.Wide local excision with histologically clean margins is the treatment mode of selection. Also, we recommendclose long-term surveillance of OGCT because of high recurrence and potential for malignancy transformation (AU)

Malignant pigmented villonodular synovitis of the temporomandibular joint with lung metastasis: a case report and review of the literature.

Malignant pigmented villonodular synovitis (PVNS) is an extremely rare lesion. Approximately 30 cases of malignant PVNS have been reported to date and of these, only 1 case involved the temporomandibular joint. Owing to the rarity of well-documented cases and the heterogeneous histologic features of this group of tumors, there has been some confusion regarding its diagnosis. The heterogeneous features of the sarcomatous areas contain fibrosarcomatous, myxosarcomatous, malignant fibrous histiocytomalike or giant cell tumorlike patterns. However, despite the absence of frank sarcomatous change in the histopathogy of PVNS, there have been 3 reported cases of metastatic lesions in the lung or lymph nodes. Here we present an additional case of clinically malignant PVNS with pulmonary metastasis after recurrence. A 29-year-old man presented in our hospital with a recurrent swelling and pain in the right preauricular area, where benign tumor had been previously resected. MRI demonstrated a large mass with a low signal intensity that seemed to demonstrate a ferromagnetic effect. Surgical resection of the lesion was performed and the diagnosis of PVNS with focal atypical cells was made. Unfortunately, at 30 months post surgery, a thoracic CT found a metastatic nodule in the left lower lobe of the lung.