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The aim of this study is to define an algorithm for the management of odontogenic keratocysts (OKCs) in order to reduce the recurrence rate (RR), morbidity and to analyse relapse risk factors. This article is a 10-years retrospective study on 67 patients treated for odontogenic keratocysts with different surgical options established on clinical and radiological evaluations. Recurrence free survival (RFS) and relapse risk factors were analysed with Kaplan-Meier method and log-rank tests, with a confidence interval set at 95 %. A literature research was performed using PubMed to find the most relevant and recent papers about the argument. Fifty-five subjects were included: 38 out of 55 patients presented the disease only once, while the others 17 patients presented at least one relapse. The total amount of histological examined lesions and relative surgical procedures was 75. More aggressive treatments showed lower recurrence rate but higher morbidity; more conservative ones had better functional and aesthetic outcomes but higher recurrence rate. Considering the literature, conservative treatments plus adjuvant procedures can reduce the RR. The recurrence rate was estimated to be 25.3 % with a median time to relapse of 24 months. Multilocularity resulted a negative prognostic factor significantly associated with recurrence free survival (p = 0.048). According to our results and to the literature, we propose a management algorithm from diagnosis to treatment of the OKCs based on dimensions and internal arrangement of lesions, type (primary lesion or recurrence), presence of bony erosions, noble structure/teeth involvement. Multilocularity represented a statistically significant risk factor for relapse. [ABSTRACT FROM AUTHOR]

Objective: To describe PNI and to evaluate its impact on disease-free (DFS) and overall survival (OS) in patients with resected pancreatic ductal adenocarcinoma (PDAC). Summary of Background Data: Although PNI is a prognostic factor for survival in many GI cancers, there is limited knowledge regarding its impact on tumor recurrence, especially in "early stage disease" (PDAC ≤20 mm, R0/ N0 PDAC). Methods: This multicenter retrospective study included patients undergoing PDAC resection between 2009 and 2014. The association of PNI with DFS and OS was analyzed using Cox proportional-hazards models. Results: PNI was found in 87% of 778 patients included in the study, with lower rates in PDAC ≤20 mm (78.7%) and in R0/N0 tumors (70.6%). PNI rate did not differ between patients who underwent neoadjuvant therapy and upfront surgery (88% vs 84%, P = 0.08). Although not significant at multivariate analysis (P = 0.07), patients with PNI had worse DFS at univariate analysis (median DFS: 20 vs 15 months, P < 0.01). PNI was the only independent predictor of DFS in R0/N0 tumors (hazard ratio [HR]: 2.2) and in PDAC ≤ 20 mm (HR: 1.8). PNI was an independent predictor of OS in the entire cohort (27 vs 50 months, P = 0.01), together with G3 tumors, pN1 status, carbohydrate antigen (CA) 19.9 >37 and pain. Conclusions: PNI represents a major determinant of tumor recurrence and patients' survival in pancreatic cancer. The role of PNI is particularly relevant in early stages, supporting the hypothesis that invasion of nerves by cancer cells has a driving role in pancreatic cancer progression. [ABSTRACT FROM AUTHOR]

There is an increased interest in venous vascular resection associated with pancreatic resection for pancreatic ductal adenocarcinoma as an upfront procedure or after neoadjuvant treatment. The aim of this study was to evaluate the impact of venous vascular resection for pancreatic ductal adenocarcinoma on postoperative and long-term outcomes. The study is a retrospective analysis of patients who underwent pancreatectomy for pancreatic head pancreatic ductal adenocarcinoma with and without venous vascular resection between January 2010 and April 2018. The impact of venous vascular resection on postoperative and pathologic data was analyzed. Univariate and multivariate analyses of predictors of disease-free and disease-specific survival were analyzed for the entire cohort. A propensity-score matched cohort analysis was subsequently performed to remove selection bias and improve homogeneity. Four hundred and eighty-one patients were included, and 126 (26%) underwent a venous vascular resection. Patients undergoing venous vascular resection had higher morbidity (64% vs 54%; P =.026) with no differences in 90-day postoperative mortality (3.1 vs 2.8%; P =.5). Venous vascular resections were also significantly associated with R1 resections (52% vs 37%; P =.002) and perineural invasion (87% vs 77%; P =.017). Five-year disease-free survival in patients with and without venous vascular resection were 7% and 20% (P =.018), respectively. Independent predictors of worse disease-free survival included venous vascular resection, positive lymph node status, and perineural invasion. Independent predictors of worse disease-specific survival were perineural invasion and positive nodal status, while adjuvant treatment was a protective factor. Five-year disease-specific survival in patients with and without venous vascular resection were 19% and 35% (P =.42). Pancreatectomy with venous vascular resection can be accomplished safely. Venous vascular resections are associated with poor prognostic factors and with a worse clinical outcome, being a significant predictor of cancer recurrence. [ABSTRACT FROM AUTHOR]

The possible benefit of frozen section (FS) analysis during (PD) for pancreatic ductal adenocarcinoma (PDAC) and of additional resection up to total pancreatectomy (TP) is debated. Aim of this work is to evaluate the prognostic role of positive FS analysis after PD for PDAC. Multicentric retrospective analysis on prospective databases of three institutions. Based on FS analysis patients were classified as FS negative/FS positive. All positive FS patients underwent extended PD (EPD) or TP. Postoperative outcomes, disease-free (DFS) and disease-specific survival (DSS) were evaluated. Of 371 patients, 58 (16%) had positive FS. This resulted in 313 (84%) SPD (standard pancreatoduodenectomy), 22 (6%) EPD and 36 (10%) TP. Postoperative mortality was higher in patients undergoing TP (11% compared to 4.5% in EPD and 1% in SPD; p = 0.01). 26% of patients underwent neoadjuvant therapy, and it did not decrease the rate of positive FS. Systemic/local relapse rates were 59% and 41% in negative FS group, and 78% and 22% in positive FS group (p = 0.031). Median DFS and DSS were 20 and 37 months in negative FS group, and 12 and 23 months in positive FS patients (p = 0.001). Independent predictors of recurrence were G3, N1/N2 status and positive FS. R1 resection, G3, N1/N2 status, perineural invasion and positive FS were independent predictors of DSS. Positive FS analysis is a poor prognostic factor after PD for PDAC. It is significantly associated with a high rate of R1 resection at final histology, PDAC recurrence and poor survival. [ABSTRACT FROM AUTHOR]

Concerns exist about a conservative management of well-differentiated nonfunctioning small pancreatic neuroendocrine tumors (NF-PanNET) in young patients and when preoperative Ki67 proliferative index is ≥3%. To evaluate an association between age, tumor size and grading in patients with sporadic NF-PanNET who underwent curative resection. Patients who underwent surgery for sporadic NF-PanNET (excluding G3) were retrospectively analyzed. Linear regression analysis was performed to evaluate a possible correlation between continuous variables, whereas multiple logistic regression analysis was performed for determining predictors of NF-PanNET-G2. Overall, 235 patients with NF-PanNET-G1/G2 were included. The median largest radiological diameter was 25 mm. Age correlated neither with tumor size (P = 0.675) nor with Ki67 index (P = 0.376). On multivariate linear regression analysis, factors independently associated with Ki67 index were NF-PanNET size (P = 0.031), perineural invasion (P = 0.004), microvascular invasion (P = 0.001) and necrosis (P = 0.009). The most accurate NF-PanNET size for predicting NF-PanNET-G2 was 25 mm. On multivariate analysis, a NF-PanNET size >25 mm was independently associated with the risk of having a PanNET-G2 (P = 0.025). No correlations exist between age and NF-PanNET size or proliferative index. Therefore, an a priori aggressive attitude is not justified in young patients with small NF-PanNET, as a long-life expectancy is probably unlikely to increase the risk of malignant transformation. [ABSTRACT FROM AUTHOR]

Background: Altered miRNA expression is an early event upon exposure to occupational/environmental carcinogens; thus, identification of a novel asbestos-related profile of miRNAs able to distinguish asbestos-induced cancer from cancer with different etiology can be useful for diagnosis. We therefore performed a study to identify miRNAs associated with asbestos-induced malignancies. Methods: Four groups of patients were included in the study, including patients with asbestos-related (NSCLCAsb) and asbestos-unrelated non-small cell lung cancer (NSCLC) or with malignant pleural mesothelioma (MPM), and disease-free subjects (CTRL). The selected miRNAs were evaluated in asbestos-exposed population. Results: Four serum miRNAs, that is miR-126, miR-205, miR-222, and miR-520g, were found to be implicated in asbestos-related malignant diseases. Notably, increased expression of miR-126 and miR-222 were found in asbestos-exposed subjects, and both miRNAs are involved in major pathways linked to cancer development. Epigenetic changes and cancer-stroma cross-talk could induce repression of miR-126 to facilitate tumor formation, angiogenesis, and invasion. Conclusions: This study indicates that miRNAs are potentially involved in asbestos-related malignancies, and their expression outlines mechanism(s) whereby miRNAs may be involved in an asbestos-induced pathogenesis. Impact: The discovery of a miRNA panel for asbestos-related malignancies would impact on occupational compensation and may be utilized for screening asbestos-exposed populations. [ABSTRACT FROM AUTHOR]

Objective: In this study, we evaluated the 8th edition of American Joint Committee on Cancer (AJCC) staging criteria and lymph node ratio (LNR) to identify patients affected by squamous cell carcinoma of the tongue (SCCT) with a poor prognosis.Study Design: Seventy-three cases of SCCT were analyzed retrospectively. Tumor staging was revised according to the 7th and 8th editions of the AJCC criteria. Depth of invasion (DOI), extranodal extension (ENE), and LNR were evaluated.Results: Twenty-five cases were reclassified: 17 patients received an upstage in the staging score, and in 8 cases in the same stage group, pT or pN was changed. In the pT-upstaged group, 7 patients experienced recurrence, and 8 died. In the pN-upstaged group, 9 patients developed recurrence, and 10 died. The number of disease recurrence or death was higher in the groups of patients who received an upstage in pN and in the staging score (P < .05). The pN-upstaged group showed worse disease-free survival (DFS) and overall survival (OS) (P < .05). LNR was higher in patients with recurrence, and among these, LNR was lower in patients with ENE (P <.05).Conclusions: The 8th edition of the AJCC criteria allows for better stratification of patients with SCCT. The implementation of ENE and LNR to pN classification seems to identify patients with worse DFS and OS. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to perform an epidemiologic analysis of cases of jaw cysts treated from 1973 to 2012 at the Dentistry and Maxillofacial Surgery Unit of the Verona Hospital, Italy, and to compare the data obtained with those published in the literature.Study Design: A retrospective survey of 2030 patients treated for jaw cysts from 1973 to 2012 was performed. The lesions were classified according to the 2005 World Health Organization histologic classification, and the following variables were analyzed: age, gender, histopathologic diagnosis, and site of onset.Results: Of 2030 total lesions, there were 1970 odontogenic cysts (97.04%), 50 nonodontogenic cysts (2.46%), and 10 pseudocysts (0.49%). Of the patients, 314 were children (15.47%), and 1716 were adults (84.53%). Mean age was 37.24 years, with a male/female ratio of 1.71:1.Conclusions: There is a wide variety of cysts, some of which are subject to variations according to gender, localization, and age. [ABSTRACT FROM AUTHOR]

Odontogenic tumors are a group of lesions arising from the odontogenic apparatus. Although the mechanism of oncogenesis and tumor progression in these lesions remains unknown, certain proteins, such as those involved in apoptosis, seem to be involved in the differentiation and proliferation of odontogenic epithelial cells. The aim of this study was to analyze the expression of p73 and TNF-related apoptosis-inducing ligand (TRAIL) in odontogenic tumors and cysts, and to clarify changes in the expression of these proteins. Immunohistochemical analysis was performed on 21 ameloblastomas, 15 keratocystic odontogenic tumors and 15 dentigerous cysts. We carried out quantitative assessment of p73 and TRAIL expression by determining the percentages of positive cells on a continuous scale. Five cases of orthokeratinized odontogenic cyst were also examined. The percentages of cells immunohistochemically positive for p73 were 52.6 ± 25.4% in ameloblastomas, 76.0 ± 13.1% in keratocystic odontogenic tumors, and 26.7 ± 30.7% in odontogenic cysts, whereas the corresponding figures for TRAIL were 57.6 ± 16.1%, 8.9 ± 10.0%, and 1.5 ± 0.5%, respectively. Imbalance of the apoptosis pathway, with dysregulation of p73 and TRAIL, seems to play a role in the oncogenesis of odontogenic tumors.(J Oral Sci 58, 459-464, 2016). [ABSTRACT FROM AUTHOR]

Background Segmental/diffuse dilatation of the main pancreatic duct (MPD) is the typical feature of combined/main-duct intraductal papillary mucinous neoplasms (CMD-IPMNs). MPD dilation in IPMNs may be also expression of mucus hypersecretion/obstructive chronic pancreatitis (OCP). The aim of this study was to evaluate the presence and extension of MPD involvement by tumor/OCP and assess the risk of overtreatment. Methods Retrospective analysis of suspected CMD-IPMNs resected between January 2009 and October 2014 were included. Pathologic correlations among MPD dilatation, IPMN, and OCP was searched. Results Overall, 93 patients were resected for suspected CMD-IPMNs. At pathology, CMD-IPMNs were found in 69 patients (74%). Branch-duct IPMNs (BD-IPMNs) were found in 8 cases (9%), pancreatic ductal adenocarcinoma (PDAC) in absence of IPMN in 9 (10%), cystic neuroendocrine tumor (NET G2) in 1 (1%), serous cystadenoma in 2 (2%), and OCP alone/mucinous metaplasia in 4 patients (4%). Overall, 18 patients (19%) underwent an overtreatment because unnecessary (2 BD-IPMNs, 2 serous cystadenomas, and 4 OCPs only) or too extensive resections (9 CMD-IPMNs and 1 PDAC with associated OCP). In these, total pancreatectomy was the most common procedure (67%). Median size of MPD in IPMN-involved area was 12 mm compared with 7 mm when only OCP was found ( P < .05). Conclusion There is a considerable risk of overtreatment in patients with a preoperative morphologic diagnosis of CMD-IPMNs. Partial pancreatectomy with margin examination should be performed instead of upfront total pancreatectomy. Radiologic observation can be considered in asymptomatic patients with “worrisome” MPD dilatation (5–9 mm) and lacking other high-risk stigmata. [ABSTRACT FROM AUTHOR]

Introduction Primary cutaneous extraskeletal Ewing’s sarcomas (ESs) are extremely rare tumors, limited to the skin and generally appear as a single small lesion, circumscribed mid-to-deep dermis or involving subcutis. Due to their rarity and morphological similarity to other cutaneous tumors, ESs are subject to being clinically and pathologically subdiagnosed. Presentation of case A 37-year-old man presented a large rapidly growing mass of the first toe measuring 9.5 × 8 cm with no radiological evidence of bone involvement. The patient underwent wide surgical tumor resection; histological, immunohistochemical and molecular evaluation confirmed the diagnosis of ESs. Postoperative examinations revealed no metastasis and after 11 months follow-up no recurrences were detected. Discussion Current literature reports only a few isolated cases or small series. ESs are generally described as small masses with a favorable clinical behavior. Despite lower extremity is a relatively frequent site, only rare and small ESs of the foot have been reported. To our knowledge the present case is the largest ES of the foot. Despite its large size, the patient did not report any metastases confirming the hypothesis of treating superficial ES with surgery alone, thus avoiding adjuvant radiotherapy and/or chemotherapy and their related side-effects. Conclusion ESs still remain exceedingly rare tumors and they could not be taken in consideration into differential diagnosis. This case represents a peculiar example of large ES in an uncommon site as the foot successfully treated with surgery alone, and may serve as an alert for those physicians who approach such rapidly growing superficial lesions. [ABSTRACT FROM AUTHOR]

Objectives: p120ctn is a component of the catenin family. To date, there have only been two studies examining expression levels of p120ctn in oral squamous cell carcinoma (OSCC). Materials and methods: Paraffined specimens of 113 OSCCs and 12 of normal mucosa were examined by immunohistochemistry. Frozen samples of 20 OSCCs and 5 of normal mucosa were examined by Western blot (WB). Results were correlated with clinicopathological parameters. Five cell lines were examined by immunofluorescence, immunocytochemistry, and WB to show immunoreactivity and cellular localization of p120ctn. Results: Altered p120ctn expression was observed in 109/113 cases of OSCC. Heterogenous cytoplasmic/nuclear expression was associated with loss of membranous distribution (88/113 cases). Complete loss of expression was noted in 21/113 cases. Increased cytoplasmic expression was evident in all positive cases, without significant correlation among p120ctn staining/pattern and grading/stage. Reduction/absence of p120ctn expression was related to poor prognosis (P < .05). Conclusion: p120ctn delocalization/loss of expression could be an independent prognostic marker in OSCC. [ABSTRACT FROM AUTHOR]

Background: Vascular endothelial growth factor (VEGF) stimulates proliferation and migration of endothelial cells, and correlates with inflammatory resolution and periodontal tissue healing. Enamel matrix derivative (EMD) seems to stimulate soft tissue healing. Our aim was to assess if topical EMD application in an instrumented periodontal pocket could affect angiogenesis at the gingival level. Methods: A total of 56 periodontal sites in 28 patients were treated with a single session of comprehensive scaling and root planing under local anesthesia after recording the clinical attachment level (CAL). EMD gel in the test site or only the vehicle propylene glycol alginate in aqueous solution in the control site of the same mouth was applied onto the root surfaces and into the pocket and left in place for 3 minutes. After 48 hours, gingival biopsies were collected for histologic and immunohistochemical analysis for VEGF and CD34 (for microvessel density [MVD] count) antibodies. Statistical comparisons were performed by analysis of variance test. Results: Endothelial VEGF expression and MVD were statistically different in the test site compared to the control site. VEGF expression and MVD of the control site were not correlated with CAL, whereas the test site showed high correlations among CAL and endothelial VEGF or MVD. Conclusions: EMD induces proliferation and viability and anglogenesis of human microvascular cells. Recent clinical and histologic studies found EMD to be useful as an adjunct to scaling and root planing in single-rooted teeth. Our findings may help to understand the mechanisms involved in soft tissue healing, through the ability of EMD to increase angiogenesis at periodontal pockets. [ABSTRACT FROM AUTHOR]

Background: Periodontal disease is one of the major problems encountered in patients with diabetes mellitus (DM), and vascular changes may contribute to periodontitis. Our aim was to investigate vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in patients with periodontitis with and without DM. Methods: Immunohistochemical detection of VEGF and MVD analysis, evaluated by CD34+ endothelial cell counts, were performed in 66 gingival samples from patients with generalized, severe, chronic periodontitis who were divided into three groups: 22 participants without systemic diseases (controls), 22 participants with type 1 DM (T1DM), and 22 participants with type 2 DM (T2DM). Results: In patients with T1DM or T2DM, positive VEGF cells were found to be significantly increased in the epithelium compared to controls. In patients with T1DM, endothelial VEGF expression and MVD were significantly greater than in patients with T2DM and controls. Conclusions: In patients with diabetes, VEGF overexpression plays a primary role in promoting the extravasation of inflammatory cells, suggesting a useful antiangiogenic strategy for periodontitis treatment. The decreased endothelial VEGF expression and MVD found in patients with T2DM may be caused by insulin resistance and endothelial dysfunction, which are often present in patients with T2DM. [ABSTRACT FROM AUTHOR]

Copyright of Serbian Dental Journal / Stomatološki Glasnik Srbije is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The aim of the present randomized, double-masked, clinical trial was to compare platelet-rich plasma (PRP) combined with a demineralized freeze-dried bone allograft (DFDBA) to DFDBA mixed with a saline solution in the treatment of human intrabony defects. Methods: Sixty interproximal intrabony osseous defects in 60 healthy, non-smoking subjects diagnosed with chronic periodontitis were treated in this study. Thirty subjects each were randomly assigned to the test group (PRP + DFDBA) or the control group (DFDBA + saline). Clinical and radiographic measurements were made at baseline and at the 12 month evaluation. Results: Compared to baseline, the 12-month results indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, bleeding on probing, probing depth, clinical attachment level, and gingival recession; P<0001 ) and radiographic parameters (hard tissue fill and bone depth reduction; P<0.001). However, the test group exhibited statistically significantly greater changes compared to the control group in probing depth reduction (4.3 ± 1.7 mm versus 2.6 ± 2.2 mm; P<0.05) and clinical attachment gain (3.5 ± 2.1 mm versus 23 ± 24 mm; P<0.001). Conclusions: Treatment with a combination of PRP and DFDBA led to a significantly greater clinical improvement in intrabony periodontal defects compared to DFDBA with saline. No statistically significant differences were observed in the hard tissue response between the two treatment groups, which confirmed that PRP had no effect on hard tissue fill or gain in new hard tissue formation. [ABSTRACT FROM AUTHOR]

Objective: We performed an immunohistochemical study in a series of ameloblastomas with different histology to explore the existence of a correlation between CD10 immunoreactivity in peritumoral stromal cells and the type of ameloblastoma with a high risk of local recurrence. Study design: A total of 45 ameloblastomas (18 unicystic [UA], 4 peripheral [PA], 23 solid/multicystic [SA]) were evaluated. Cases showing immunoreactivity for CD10 in < and ≥10% of stromal cells around tumoral epithelial islands, were considered, respectively, negative and positive. Correlations between stromal CD10 expression and histopathologic types with low and high risk of recurrence were evaluated by statistical analysis. Results: SA cases showed a significantly higher percentage of stromal CD10-positive cells than the UA and PA variants. A strong intensity of immunostaining was observed only in SA. Conclusions: Our results suggest that CD10 expression might be associated with stromal invasion in ameloblastoma variants with a high risk of recurrences. [Copyright &y& Elsevier]

Copyright of Implant Dentistry is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: A dentinogenic ghost cell tumor is a locally invasive neoplasm that is characterized by ameloblastoma-like islands of epithelial cells in a mature connective tissue stroma. Methods: A 43-year-old male patient presented a well-circumscribed sessile, exophytic mass of the gingiva with a diameter of 2 cm located in the canine area of the right maxilla. The lesion was enucleated. Results: The lesion showed odontogenic epithelium, ghost cells, dentinoid material, and giant cells. The final microscopic diagnosis was a dentinogenic ghost cell tumor. Conclusions: A dentinogenic ghost cell tumor is an extremely rare tumor, and only a few cases have been reported in the English literature. The peripheral, extraosseous lesion can be easily confused with other gingival lesions such as reactive or inflammatory lesions or other peripheral odontogenic tumors. The clinical appearance of all of these lesions is similar; therefore, the definitive diagnosis depends on histology, and a biopsy with a microscopic examination is mandatory. [ABSTRACT FROM AUTHOR]

Abstract: Titanium is the gold standard among materials used for prosthetic devices because of its good mechanical and chemical properties. There are three allotropic forms of titanium dioxide: brookite, rutile, and anatase. Anatase can be prepared as a colloidal suspension and used to coat surfaces. Anatase coating (AC) can potentially have biological effects and specifically can induce bone formation. To obtain more information about the osteogenic effect of AC in comparison to to titanium we used microRNA (miRNA) microarray techniques to investigate the translation regulation in osteoblasts exposed to both titanium and AC. There were three upregulated miRNAs (mir-1, mir-34c, mir-210) and eight downregulated miRNAs (mir-23b, mir-377, mir-22, mir-93, mir-422b, mir-17-5p, mir-24, mir-130b) for false discovery rate = 0 and score >3. The data reported are relevant to understand the molecular mechanism of bone regeneration and as a model for comparing other materials with similar clinical effects. [Copyright &y& Elsevier]

Abstract: The KAI-1 tumor suppressor gene is widely distributed in normal tissues and its down-regulation may be correlated with the invasive phenotype and metastases in several different epithelial tumors. The aim of the present study was an evaluation of KAI-1 expression in radicular cysts (RC), follicular cysts (FC), orthokeratinized keratocysts (OOKC), and parakeratinized keratocysts (POKC). Eighty-five odontogenic cysts, 28 RC, 22 FC, and 35 OKC (16 OOKC, 19 POKC) were selected. All the POKC were negative and only four of 16 of the OOKC were positive for KAI-1. On the contrary, all RC and FC cases were positive and immunoreactivity for KAI-1 was detected throughout all the layers of the cyst epithelium. The lack of KAI-1 expression in POKC could help to explain the differences in the clinical and pathologic behavior of OKC and, according to what has been reported for epithelial tumors, could be related to the increased aggressive behavior and invasiveness of OKC. [Copyright &y& Elsevier]

Summary: p63 belongs to a protein family that includes 2 structurally related proteins, p53 and p73. The aim of this study was to investigate the biologic role of p63 in oral tumorigenesis and its possible role as prognostic marker in oral cancer. Ninety-four cases of oral squamous cell carcinoma and 10 cases of normal mucosa were analyzed for p63 expression by immunohistochemistry. Normal oral mucosa showed a basal and parabasal expression of p63. Five (5.3%) cases of oral cancer showed less than 10% of positive tumor cells; in 33 (35.1%) cases the positive tumor cells comprised between 10% and less than 30%, in 36 (38.3%) cases the positive tumor cells comprised between 30% and less than 50%, and in 20 (21.3%) cases the positive tumor cells were more than 50%. There was also a statistically significant correlation between p63 expression and tumor differentiation: p63 expression was amplified in poorly differentiated tumors (P < .05). When analyzed for prognostic significance, patients with perineural infiltration had poorer survival rates than the group with no perineural infiltration (P < .05) and patients with increased p63 expression had poorer survival rates than the group with reduced p63 expression (P < .05). The statistical analysis showed no significant correlation between p63 expression, sex, age, tumor size, staging, recurrence, and metastasis. Cases with diffuse p63 expression were more aggressive and poorly differentiated and related to a poorer prognosis. These data suggest that p63 expression may be useful to identify cases of oral squamous cell carcinoma with more aggressive and invasive phenotype providing novel diagnostic and prognostic information on individual patient survival with oral cancers. [ABSTRACT FROM AUTHOR]

Background: Mucosal malignant melanoma of the of the head and neck is a rare neoplasm, accounting for about 0.2% of ail melanomas. We present the clinopathological findings of a case. Methods: An 83-year-old woman presented with a dark reddish pigmented lesion which had appeared 3 years previously. Results: Clinical examination revealed a sessile lesion, 1.5 cm in diameter, located on the vestibular maxillary gingiva next to the first molar area. Microscopic analysis of the neoplasm showed epithelioid cells with prominent nucleoli aggregated in solid nests, Cytoplasmic melanin pigmentation was present. The neoplastic cells were positive for HMB-45 and S100 protein. The final histologic diagnosis was primary malignant melanoma of the gingiva. Physical examination and a computerized tomography scan of the neck, liner, and lungs ruled out the possibility of occult melanoma lesions elsewhere in the body. Conclusion: The prognosis for patients with oral malignant melanoma is extremely poor. Earlier recognition of this condition simplifies treatment and greatly improves the prognosis for these patients. [ABSTRACT FROM AUTHOR]

This study investigated whether or not an ameloblastoma developing in the wall of a dentigerous cyst is a distinct lesion from the unicystic ameloblastoma. An immunohistochemical evaluation of Ki-67 in dentigerous cysts, unicystic ameloblastomas, and ameloblastomas arising in dentigerous cysts was done. The values of Ki-67 positivity were 3.14 for the dentigerous cyst, between 5.32 and 16.56 for unicystic ameloblastoma, and 11.77 for ameloblastoma arising in a dentigerous cyst. Statistically significant differences were found between the dentigerous cyst and the unicystic ameloblastoma and between the dentigerous cyst and the ameloblastoma arising from a dentigerous cyst. No statistically significant difference was present between unicystic ameloblastoma and ameloblastoma arising from dentigerous cyst. These immunohistochemical data confirm the hypothesis that an ameloblastoma arising from a dentigerous cyst has a similar biological behavior to the unicystic ameloblastoma and should be considered as merely a histologic variant. [Copyright &y& Elsevier]

Vascular endothelial growth factor (VEGF) is a glycoprotein that has the capability to increase vascular proliferation and permeability. VEGF has been found to be expressed in several different types of tumors, and it may contribute to the progression of malignant tumors. Immunostaining for VEGF and factor VIII was performed in normal healthy pulps and in irreversible pulpitis. In both cases the vessels were always positive for VEGF. Our immunohistochemical data show that the expression of VEGF was strongly positive in the inflammatory infiltrate in irreversible pulpitis. VEGF expression in the stromal cells in healthy pulps ranged from 20 to 100% (with a mean of 68.82), and in irreversible pulpitis ranged from 0 to 100% (with a mean of 62.35%); this difference was statistically significant (p = 0.05). This down-regulation in the stromal cells in irreversible pulpitis could be due to the presence, in a low compliance system such as the dental pulp, of inflammatory infiltrate. VEGF is probably a factor implicated in the etiology and progression of pulpitis. The microvessel density in healthy pulps was 90.00 ± 27.5, while, in irreversible pulpitis, it was 56.68 ± 21.15. This difference was statistically significant (p = 0.001). The decrease in microvessel density in irreversible pulpitis could be related to failing vascular function and blood flow decrease. [Copyright &y& Elsevier]