Evaluation of peripheral nerve fibers and mast cells in burning mouth syndrome.

Emerging evidence has revealed a cross-talk in the etiopathogenesis of burning mouth syndrome (BMS) related to peripheral nerve fibers (NF) and neuropeptides secreted by mast cells. Here, we investigated the S-100+ density and PGP 9.5+ integrity of peripheral NF and the tryptase+ mast cell density in the oral mucosa of BMS patients and healthy individuals. A total of 23 oral mucosa specimens (12 BMS and 11 controls) were evaluated. The clinical diagnosis of BMS was based on a careful examination, excluding other local and systemic causes. Samples were taken from an incisional biopsy of the tongue mucosa of individuals with symptomatic BMS, while the margins of the non-neoplastic tongue biopsy served as controls of healthy individuals. Immunohistochemistry was performed to determine the density/mm2 of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells. Similar densities of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells were found in cases of BMS, with a median value of 3.70, 0.70, and 29.24/mm2, respectively, and in the control group, with a median value of 2.60, 0.80, and 26.01/mm2, respectively (p > 0.05). Moreover, the relationship between S100+ and PGP 9.5+ peripheral NF was the same in both groups (p = 0.70). This study demonstrated that there were no alterations in the density and integrity of peripheral NF in the tongue of symptomatic BMS patients. However, the sensitization of peripheral NF in this disease may not depend on mast cell density.

Evaluation of peripheral nerve fibers and mast cells in burning mouth syndrome

Abstract Emerging evidence has revealed a cross-talk in the etiopathogenesis of burning mouth syndrome (BMS) related to peripheral nerve fibers (NF) and neuropeptides secreted by mast cells. Here, we investigated the S-100+ density and PGP 9.5+ integrity of peripheral NF and the tryptase+ mast cell density in the oral mucosa of BMS patients and healthy individuals. A total of 23 oral mucosa specimens (12 BMS and 11 controls) were evaluated. The clinical diagnosis of BMS was based on a careful examination, excluding other local and systemic causes. Samples were taken from an incisional biopsy of the tongue mucosa of individuals with symptomatic BMS, while the margins of the non-neoplastic tongue biopsy served as controls of healthy individuals. Immunohistochemistry was performed to determine the density/mm2 of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells. Similar densities of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells were found in cases of BMS, with a median value of 3.70, 0.70, and 29.24/mm2, respectively, and in the control group, with a median value of 2.60, 0.80, and 26.01/mm2, respectively (p > 0.05). Moreover, the relationship between S100+ and PGP 9.5+ peripheral NF was the same in both groups (p = 0.70). This study demonstrated that there were no alterations in the density and integrity of peripheral NF in the tongue of symptomatic BMS patients. However, the sensitization of peripheral NF in this disease may not depend on mast cell density.

Assessment of child's dental anxiety/fear and stress during dental treatment: a systematic review by CEDACORE

Abstract: There is a lack of evidence on the correlation between salivary biomarkers and subjective measures of dental fear and anxiety in children. This systematic review aimed to retrieve the scientific evidence comparing the results of dental anxiety measured by salivary biomarkers with patient-reported outcomes in pediatric dental setting. The PECOS was as follows: population: pediatric patients aged ≤ 18 years; exposure: patient-reported outcome measures, such as scales and/or questionnaires; comparator: salivary biomarkers; outcome: anxiety, fear, phobia or stress during dental treatment; study design: observational studies or controlled trials. Electronic searches were conducted in PubMed, Scopus, Web of Science, and Ovid databases. Studies that compared scales/questionnaires and salivary biomarkers for the evaluation of dental anxiety, fear, and stress in children/adolescents during dental treatment were included. Certainty of evidence was assessed with GRADE. Risk of bias of the included studies was assessed with the Cochrane tool or the University of Adelaide tool. From the 314 studies identified, eight were included. Participants' age ranged from three to 13 years. The most used salivary biomarkers and instruments were cortisol and the Dental Subscale of the Children's Fear Survey Schedule, respectively. Most studies showed a weak correlation between objective and subjective measures. The main issues regarding bias were on allocation concealment, blinding of assessors, follow up, and exposure assessment. Certainty of evidence was low/very low. Evidence of salivary biomarkers and patient-reported outcome measures to investigate anxiety, fear and stress in children during in the dental environment is limited. There was no correlation between subjective and objective measures in almost all included studies.

Biological effects of formulation containing curcuminoids and Bidens Pilosa L. in oral carcinoma cell line.

FITOPROT, which contains curcuminoids and Bidens pilosa L. extract, is an innovative mucoadhesive formulation indicated for the topical treatment of chemoradiotherapy-induced oral mucositis (OM) in patients with advanced and visible oral squamous cell carcinoma. The formulation is used as a mouthwash directly on tumor tissue of patients with advanced neoplasms, without triggering cancer cell proliferation or tumor invasiveness. Thus, the aim of this study was to evaluate the biological effects of FITOPROT on an oral squamous cell carcinoma cell line (SCC-4). The viability of SCC-4 cells was assessed after exposure to FITOPROT using MTT reduction assay. The effects of the mucoadhesive formulation on cell cycle progression and cell death parameters were evaluated using flow cytometry. In addition, the inflammatory profile of the tumor cells was evaluated using the cytometric bead array (CBA) assay. FITOPROT promoted a concentration-dependent decrease in cell viability and cell cycle arrest at the G2/M phase (p < 0.05). Mitochondrial membrane potential was also altered after exposure to the formulation (p < 0.05), in parallel with a reduction in VEGF and IL-8 production (p = 0.01 and p = 0.05, respectively). In summary, the results indicate that FITOPROT reduces SCC-4 cell viability, promotes cell cycle arrest, modulates mitochondrial membrane potential, and exhibits antiangiogenic and anti-inflammatory properties, thus indicating its potential for topical use in patients with OM and visible tumors in the mouth.

Chronic inflammatory periapical diseases: a Brazilian multicenter study of 10,381 cases and literature review.

The aim of this study was to investigate the epidemiological and clinical characteristics of chronic inflammatory periapical diseases in different regions of Brazil and to compare with data from the literature. A multicenter study was carried out in four Brazilian referral centers in oral diagnosis. Histopathological records were reviewed, and all cases diagnosed microscopically as periapical granuloma, radicular cyst, and periapical abscess were included. Demographic and clinical data were collected. Descriptive statistics and Pearson's chi-square test were performed. A total of 10,381 cases of chronic inflammatory periapical diseases were found (13.8% of 74,931 archived specimens) over a period of 65 years. Radicular cysts were the most common lesion (59.9%). Women (56.1%) with a mean age of 37.01 years old (range 13 to 100 ± 14.42) and people of white skin color (59.2%) were the most affected individuals by chronic inflammatory periapical diseases. The lesions were generally asymptomatic (28.1%), located in the maxilla (60.1%), and posterior region (49.8%). The radicular cysts were larger when compared to periapical granulomas (p < 0.001). The disagreement between the clinical and histopathological diagnoses was higher when the final diagnosis was a periapical granuloma (p < 0.001). Chronic inflammatory periapical diseases continue to be common lesions affecting mainly adults. This should be a consequence of the burden of untreated caries in permanent teeth. Women are more affected and radicular cyst was the most common lesion.

Photobiomodulation reduces the impact of radiotherapy on oral health-related quality of life due to mucositis-related symptoms in head and neck cancer patients.

To assess the effectiveness of photobiomodulation therapy (PBMT) in the oral health-related quality of life (OHRQoL) of patients with head and neck cancer undergoing radiotherapy (RT), using the Oral Health Impact Profile-14 (OHIP-14) and the Patient-Reported Oral Mucositis (OM) Symptoms Scale (PROMS), and to correlate OM degree with the PROMS and OHIP-14 scores. Forty-eight patients undergoing RT for head and neck cancer were randomly assigned into two groups: PBMT group (n = 25)-daily PBMT associated with a preventive oral care program (POCP); and control group (n = 23)-receiving POCP exclusively. OHRQoL was assessed using the PROMS and OHIP-14 questionnaires. OM degrees were classified according to the World Health Organization and the National Cancer Institute scales. Assessments were performed at the 1st, 7th, 14th, 21st, and 30th RT sessions. PBMT was effective in preventing and treating severe OM. Both groups showed increased OHRQoL impacts throughout the RT sessions; however, higher impacts were observed in the control group, mainly at the final stage of treatment (21st and 30th RT sessions). Significant correlations were found between the severity of OM and PROMS scores in the total sample and the control group at all RT periods. PROMS and OM scores were positive correlated at 14th, 21st, and 30th RT sessions in the control group, suggesting that this instrument is useful in classifying OM. PBMT was effective in treating and preventing severe OM and OM-related symptoms, and with consequent positive impacts in OHRQoL in head and neck patients undergoing RT. The PROMS scale was helpful instrument for assessment of the severity of OM. Brazilian Clinical Trials database (ReBEC - RBR-5h4y4n), registered in Aug, 24th 2017.

Biological effects of formulation containing curcuminoids and Bidens Pilosa L. in oral carcinoma cell line

Abstract: FITOPROT, which contains curcuminoids and Bidens pilosa L. extract, is an innovative mucoadhesive formulation indicated for the topical treatment of chemoradiotherapy-induced oral mucositis (OM) in patients with advanced and visible oral squamous cell carcinoma. The formulation is used as a mouthwash directly on tumor tissue of patients with advanced neoplasms, without triggering cancer cell proliferation or tumor invasiveness. Thus, the aim of this study was to evaluate the biological effects of FITOPROT on an oral squamous cell carcinoma cell line (SCC-4). The viability of SCC-4 cells was assessed after exposure to FITOPROT using MTT reduction assay. The effects of the mucoadhesive formulation on cell cycle progression and cell death parameters were evaluated using flow cytometry. In addition, the inflammatory profile of the tumor cells was evaluated using the cytometric bead array (CBA) assay. FITOPROT promoted a concentration-dependent decrease in cell viability and cell cycle arrest at the G2/M phase (p < 0.05). Mitochondrial membrane potential was also altered after exposure to the formulation (p < 0.05), in parallel with a reduction in VEGF and IL-8 production (p = 0.01 and p = 0.05, respectively). In summary, the results indicate that FITOPROT reduces SCC-4 cell viability, promotes cell cycle arrest, modulates mitochondrial membrane potential, and exhibits antiangiogenic and anti-inflammatory properties, thus indicating its potential for topical use in patients with OM and visible tumors in the mouth.

Chronic inflammatory periapical diseases: a Brazilian multicenter study of 10, 381 cases and literature review

Abstract The aim of this study was to investigate the epidemiological and clinical characteristics of chronic inflammatory periapical diseases in different regions of Brazil and to compare with data from the literature. A multicenter study was carried out in four Brazilian referral centers in oral diagnosis. Histopathological records were reviewed, and all cases diagnosed microscopically as periapical granuloma, radicular cyst, and periapical abscess were included. Demographic and clinical data were collected. Descriptive statistics and Pearson's chi-square test were performed. A total of 10,381 cases of chronic inflammatory periapical diseases were found (13.8% of 74,931 archived specimens) over a period of 65 years. Radicular cysts were the most common lesion (59.9%). Women (56.1%) with a mean age of 37.01 years old (range 13 to 100 ± 14.42) and people of white skin color (59.2%) were the most affected individuals by chronic inflammatory periapical diseases. The lesions were generally asymptomatic (28.1%), located in the maxilla (60.1%), and posterior region (49.8%). The radicular cysts were larger when compared to periapical granulomas (p < 0.001). The disagreement between the clinical and histopathological diagnoses was higher when the final diagnosis was a periapical granuloma (p < 0.001). Chronic inflammatory periapical diseases continue to be common lesions affecting mainly adults. This should be a consequence of the burden of untreated caries in permanent teeth. Women are more affected and radicular cyst was the most common lesion.

FoxP3+ regulatory T cells in oral tongue squamous cell carcinoma in young and older patients.

Regulatory T (Treg) cells can suppress antitumor immune response, but little is known about possible age-related differences in the number of these cells in the microenvironment of oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to determine the number of FoxP3+ Treg cells in the microenvironment of OTSCC in young (≤ 45 years) and older (≥ 60 years) patients, and to correlate the findings with clinicopathological parameters (sex, tumor size/extent, regional lymph node metastasis, clinical staging, and histopathological grade of malignancy). Forty-eight OTSCCs (24 diagnosed in young patients and 24 diagnosed in older patients) were selected. Lymphocytes exhibiting nuclear immunopositivity for FoxP3 were quantified at the tumor invasive front and the results were analyzed statistically using the non-parametric Mann-Whitney test. FoxP3+ lymphocytes were observed in all cases assessed. The number of FoxP3+ lymphocytes in OTSCC tended to be higher in older patients (p = 0.055). Analysis of OTSCC in males and in early clinical stages revealed a higher number of Treg cells in older patients than in young ones (p < 0.05). In older patients, the number of Treg cells tended to be higher in smaller tumors (p = 0.079). Tumors with intense inflammatory infiltrate exhibited a larger number of Treg cells, both in young (p = 0.099) and older patients (p = 0.005). The results suggest a greater participation of Treg cells in immunoinflammatory responses in the microenvironment of OTSCC in older patients, particularly in males and in early stages.

Mast Cells and Blood Vessels Profile in Oral Carcinogenesis: An Immunohistochemistry Study.

BACKGROUND: The objectives of the present study were to evaluate angiogenesis and mast cell density in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: This was an observational, retrospective and quantitative study. The samples consisted of 60 tissue specimens from patients with squamous cell carcinoma, epithelial dysplasia and controls (n=20/group). Immunohistochemistry was performed using an anti-tryptase antibody to mast cells and anti-CD31 and anti-CD34 for blood vessels and we count the number of mast cells and determine the percentage of CD31 and CD34 antibody staining (vascular density). RESULTS: The mast cells had lower density in OSCC compared to control and dysplasia (p = 0.009). In angiogenesis, the expression of CD31 showed a higher percentage of blood vessels in OSCC (p < 0.001), however, CD34 showed no difference between groups (p=0.092). The CD31 antibody presented as a high immunostaining in oral mucosa than CD34. CONCLUSIONS: The increased vascularity in squamous cell carcinoma suggests that angiogenesis begins when malignant transformation starts that seems to be inversely associated with the number of mast cells.

A Rare Case of an Aggressive Clear Cell Variant of Calcifying Epithelial Odontogenic Tumor in the Posterior Maxilla.

A clear cell variant of calcifying epithelial odontogenic tumor is a rare benign odontogenic neoplasm, accounting for 33 cases described in the literature. In this article, we report a challenging example of clear cell variant of calcifying epithelial odontogenic tumor of the posterior maxilla in a 45-year-old female patient showing locally aggressive growth and recurrence. Microscopically, islands of polyhedral cells containing abundant cytoplasm, well-developed intercellular bridges blended with clear cells were observed. The nuclei were frequently pleomorphic and permeated by hyaline calcified material. Immunohistochemistry revealed positivity for pan-cytokeratin (AE1/AE3), cytokeratins (CK-14 and CK-19), Bcl-2, p53, and p63. The Ki-67 proliferative index was ~10%. As odontogenic tumors are rare, when a significant clear cell component is observed, the differential diagnosis with other lesions of the jaws with similar morphology, including other odontogenic tumors with prominent clear cell component, clear cell odontogenic carcinomas, and metastatic tumors, is difficult.

A multicenter study of oral sarcomas in Brazil.

OBJECTIVES: The aim of this study was to investigate the prevalence of oral sarcomas from geographic regions of Brazil. MATERIALS AND METHODS: A cross-sectional study was conducted on biopsies obtained from January 2007 to December 2016 at twelve Brazilian oral and maxillofacial pathology centres. Gender, age, evolution time, clinical aspects, tumour location, tumour size at diagnosis, radiographic aspects and histopathological diagnosis were evaluated. Data were analysed using descriptive statistical methods. RESULTS: From 176,537, a total of 200 (0.11%) oral sarcomas were reported, and the most prevalent were osteosarcomas (74 cases; 37%) and Kaposi's sarcomas (52 cases; 26%). Males were more affected than females at a mean age of 32.2 years old (range of 3-87 years). The most common symptoms were swelling¸ localised pain and bleeding at a mean evolution time of 5.14 months (range <1-156 months). The lesions were mostly observed in the mandible (90 cases; 45%), with a mean tumour size of 3.4 cm (range of 0.3-15 cm). Radiographically, the lesions presented a radiolucent aspect showing cortical bone destruction and ill-defined limits. CONCLUSIONS: Oral sarcomas are rare lesions with more than 50 described subtypes. Osteosarcomas and Kaposi's sarcomas were the main sarcomas of the oral cavity in Brazil.

Clinicopathological and immunohistochemical features of the oral lymphoepithelial cyst: A multicenter study.

BACKGROUND: Analyze the clinical, demographic, histopathological, and immunohistochemical features of oral lymphoepithelial cyst (OLEC). METHODS: Samples were retrospectively retrieved from five oral pathology services. Clinical and demographic data were collected from patient charts. Histopathological and immunohistochemical (CD3 and CD20) features were evaluated. Data analysis involved descriptive statistics and bivariate analyses (P ≤ .05). RESULTS: Seventy-seven cases were found among a total of 146 150 specimens (0.05%). OLEC was predominantly diagnosed in females (70.1%). Mean patient age was 46.51 years. The lesions arose mainly on the lateral border of the tongue (40.3%), measured up to 1 cm (61.0%), and were asymptomatic (64.9%). Twenty-four lesions (31.2%) were white. Forty-one cases (53.2%) presented lymphocytic inflammatory infiltrate with no specific arrangement. The cystic lining was composed of a non-keratinized stratified epithelium (59.7%) presenting hyperplasia (39.0%). Connection with the surface, epithelium was found in 23 cases (29.9%) and 31 (40.3%) cases had two or more cystic cavities. The lumen content was predominantly desquamated cells (48.1%). Subgemmal neurogenous plaque was found in 11/42 (26.2%) cases involving the tongue. CD20+ cells predominated in 36/63 cases (57.2%), and lymphocytic inflammatory infiltrate was not always continuous around the cystic cavity (52.4%). CONCLUSION: Lymphoepithelial cyst is an uncommon lesion of the oral cavity. The present study offers the largest sample of OLEC for which clinical, demographic, histopathological, and immunohistochemical features were evaluated. The clinical and demographic findings were similar to those described in previous reports, but the microscopic analyses revealed interesting aspects of the cystic epithelium and the lymphocytic inflammatory infiltrate in OLEC.

FoxP3+ regulatory T cells in oral tongue squamous cell carcinoma in young and older patients

Abstract Regulatory T (Treg) cells can suppress antitumor immune response, but little is known about possible age-related differences in the number of these cells in the microenvironment of oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to determine the number of FoxP3+ Treg cells in the microenvironment of OTSCC in young (≤ 45 years) and older (≥ 60 years) patients, and to correlate the findings with clinicopathological parameters (sex, tumor size/extent, regional lymph node metastasis, clinical staging, and histopathological grade of malignancy). Forty-eight OTSCCs (24 diagnosed in young patients and 24 diagnosed in older patients) were selected. Lymphocytes exhibiting nuclear immunopositivity for FoxP3 were quantified at the tumor invasive front and the results were analyzed statistically using the non-parametric Mann-Whitney test. FoxP3+ lymphocytes were observed in all cases assessed. The number of FoxP3+ lymphocytes in OTSCC tended to be higher in older patients (p = 0.055). Analysis of OTSCC in males and in early clinical stages revealed a higher number of Treg cells in older patients than in young ones (p < 0.05). In older patients, the number of Treg cells tended to be higher in smaller tumors (p = 0.079). Tumors with intense inflammatory infiltrate exhibited a larger number of Treg cells, both in young (p = 0.099) and older patients (p = 0.005). The results suggest a greater participation of Treg cells in immunoinflammatory responses in the microenvironment of OTSCC in older patients, particularly in males and in early stages.

Cell cycle markers and apoptotic proteins in oral tongue squamous cell carcinoma in young and elderly patients.

The immunoexpression of p16, p53, and Bax in oral tongue squamous cell carcinoma (OTSCC) in young and elderly patients is assessed based on clinical and morphological parameters. The sample consists of 60 OTSCC cases: 30 in young (age ≤ 45 years) and 30 in elderly (age ≥ 60 years) patients. Clinical (tumor size, regional node metastasis, distant metastasis, and clinical stage) and morphological (histological grade of malignancy) parameters were evaluated. Immunohistochemical quantitative analysis was performed using anti-p16, anti-p53, and anti-Bax antibodies. None of the evaluated proteins exhibited statistically significant differences between young and elderly patients (p>0.05). There was a significant association of p16 immunoexpression with clinical parameters in elderly patients. There were no associations of p53 and Bax with any of the clinico-morphological parameters. Correlations between p16 and Bax and between p53 and Bax immunoexpression were observed in young patients (r = 0.363; p = 0.048) and in elderly patients (r = 0.433; p = 0.017), respectively. In conclusion, the assessed proteins could not be used to determine differences in the biological behavior of OTSCC between young and elderly patients. Therefore, all proteins activated the pro-apoptotic pathway of OTSCC in both groups.

Crossover studies of pediatric dental sedation are inappropriate

Abstract Crossover studies continue to be published in spite of warnings about their inherent risks in relation to behavioral outcomes. This study took the opportunity of access to secondary data analysis in order to demonstrate the impact of a crossover design on the outcomes of randomized clinical trials aimed at the behavior of children during dental treatment. We evaluated the effect of the sequence of sedative administration, the sedative and the participant's age on the behavior of children undergoing two sequential dental visits. Eighteen uncooperative healthy young children were equally randomly assigned to: (G1) 1.0 mg/kg oral midazolam (first session) and oral placebo (second session); (G2) oral placebo (first) and 1.0 mg/kg oral midazolam (second). One trained observer assessed children's behavior. Data were analyzed by three-way mixed ANOVA. Both midazolam [mean(SD); 71.7%(16.5)] and placebo [48.6%(33.1)] produced more struggling behavior when they were administered in the first session compared to the second one (p=0.001). For the placebo, children aged 2-3 years exhibited more struggling behavior [G1 54.9%(36.2); G2 80.5%(8.3)] than those aged 4-5 years (p=0.04). Also, the reduction of percentage of struggling behavior was higher in G1 for older children (76.2%) and in G2 for younger children (32.9%). There were significant interactions between drug and sequence of administration, and between drug and age. The results of our study confirm the conventional wisdom that crossover study design is inappropriate to evaluate children's behavior/anxiety related-dental treatment under sedation and the results of crossover studies of dental sedation should be treated with extreme caution.

Resumo Pouco se sabe sobre o impacto de um delineamento cruzado nos desfechos de ensaios clínicos randomizados voltados ao comportamento de crianças durante tratamento odontológico. Este estudo objetivou avaliar o efeito da sequência de administração do sedativo, da droga em si e da idade dos participantes no comportamento de crianças que receberam duas consultas odontológicas consecutivas. Dezoito crianças saudáveis não colaboradoras, 2-5 anos de idade, foram randomizadas em dois grupos: G1 - 1,0 mg/kg midazolam oral (primeira sessão) e placebo oral (segunda sessão); G2 - placebo (primeira) e 1,0 mg/kg midazolam oral (segunda). Um observador treinado avaliou o comportamento infantil. Os dados foram analisados por ANOVA de três fatores (alfa=0,05). Midazolam [média(DP); 71,7%(16,5)] e placebo [48,6%(33,1)] resultaram em mais comportamento não cooperativo quando administrados na primeira sessão comparado com a segunda (p=0,001). Com o uso do placebo, crianças de 2-3 anos de idade exibiram mais comportamento não cooperativo [G1 54,9%(36,2); G2 80,5%(8,3)] que as de 4-5 anos de idade (p=0,04). Além disso, a porcentagem de redução do comportamento não cooperativo foi maior em crianças mais velhas em G1 (76,2%) e em crianças mais novas em G2 (32,9%). Considerando a avaliação do comportamento infantil sob sedação, a primeira sessão odontológica influenciou a segunda visita. Os resultados deste estudo confirmam a especulação de que o delineamento cruzado é inadequado para avaliar o comportamento odontológico relacionado à ansiedade/comportamento infantil; os resultados dos ensaios cruzados de sedação odontológica devem ser tratados com extrema cautela.

Prognostic importance of the lymphovascular invasion in head and neck adenoid cystic carcinoma: A systematic review and meta-analysis.

The presence of lymphovascular invasion is considered a prognostic determinant for different human neoplasms and is frequently taken into account by surgeons and oncologists to determine patients' treatment. However, the exact frequency of this microscopic event and its prognostic impact for patients affected by adenoid cystic carcinoma (AdCC) remains unclear. Therefore, the aim of this study was to carry out a systematic review and meta-analysis to address the prevalence and the prognostic potential of lymphovascular invasion in head and neck AdCC. A literature search on PubMed, Scopus, ClinicalTrials.gov, Web of Science and ProQuest databases was undertaken in January 2019. The primary outcomes of interest were overall survival (OS) and disease-free survival (DFS). The relative frequency of lymphovascular invasion and its possible association with other clinicopathological parameters were addressed. A total of 22 studies and 2117 patients were included in this study. The frequency of lymphovascular invasion ranged from 5.2% to 72.5%. Lymphovascular invasion was associated with an increased likelihood of lymph node metastasis (OR = 2.58; 95% CI 1.61-4.12; p = 0.0001) and death (OR = 3.09; 95% CI 1.82-5.26; p = 0.0001), solid/higher-grade AdCC were more likely to present lymphovascular invasion (OR = 5.51; 95% CI 1.87-16-21; p = 0.002) and patients with this microscopic finding had a significantly lower OS (HR = 8.30; 95% CI 1.68-40.91; p = 0.009) and DFS (HR = 3.76; 95% CI 1.13-12.53; p = 0.03). In conclusion, lymphovascular invasion seems to be a significant predictor of poor prognosis for head and neck AdCC patients.

Mesenchymal Stem Cell Marker Expression in Periapical Abscess.

INTRODUCTION: There is evidence that acute periapical lesions present a greater potential for cyst formation. Recently, it was found that these lesions have cells with characteristics of pluripotent stem cells, which may influence cyst development. However, a more complete phenotype investigation of stem cells in a specific sample of periapical abscesses is required. The aim of this study was to analyze the immunohistochemical expression of mesenchymal stem cell (MSC) markers in periapical abscesses and to evaluate differences in their expression in relation to acute and chronic periapical lesions. METHODS: Immunohistochemistry was used to access MSC marker expression (CD44, CD73, and CD105) in samples of periapical abscesses (n = 10), granulomas (n = 10), cysts (n = 10), and apical papillae (n = 10). Immunohistochemical expression was evaluated by a quantitative scoring system. The chi-square test was used to assess the association between MSC marker expression and the histopathological diagnosis at a 5% significance level. RESULTS: CD44 and CD73 immunostaining was observed in mesenchymal cells located in the outer portion of the abscess and periapical cyst specimens. CD105 immunoexpression was found predominantly in mesenchymal and vascular endothelial cells of the lesions studied. MSC marker expression was higher in the periapical abscesses, with a significant association between MSCs and the histopathological diagnosis of an abscess (P < .05). CONCLUSIONS: The periapical region is a rich source of MSCs. The greater presence of MSCs in periapical abscesses found in this study could hold an important clue into understanding the pathological pathway of periapical cyst formation.

Effect of photobiomodulation on the severity of oral mucositis and molecular changes in head and neck cancer patients undergoing radiotherapy: a study protocol for a cost-effectiveness randomized clinical trial.

BACKGROUND: Oral mucositis (OM) is the most frequent and debilitating acute side effect associated with head and neck cancer (HNC) treatment. When present, severe OM negatively impacts the quality of life of patients undergoing HNC treatment. Photobiomodulation is a well-consolidated and effective therapy for the treatment and prevention of severe OM, and is associated with a cost reduction of the cancer treatment. Although an increase in the quality of life and a reduction in the severity of OM are well described, there is no study on cost-effectiveness for this approach considering the quality of life as a primary outcome. In addition, little is known about the photobiomodulation effects on salivary inflammatory mediators. Thus, this study aimed to assess the cost-effectiveness of the photobiomodulation therapy for the prevention and control of severe OM and its influence on the salivary inflammatory mediators. METHODS/DESIGN: This randomized, double-blind clinical trial will include 50 HNC patients undergoing radiotherapy or chemoradiotherapy. The participants will be randomized into two groups: intervention group (photobiomodulation) and control group (preventive oral care protocol). OM (clinical assessment), saliva (assessment of collected samples) and quality of life (Oral Health Impact Profile-14 and Patient-Reported Oral Mucositis Symptoms questionnaires) will be assessed at the 1st, 7th, 14th, 21st and 30th radiotherapy sessions. Oxidative stress and inflammatory cytokine levels will be measured in the saliva samples of all participants. The costs are identified, measured and evaluated considering the radiotherapy time interval. The incremental cost-effectiveness ratio will be estimated. The study will be conducted according to the Brazilian public health system perspective. DISCUSSION: Photobiomodulation is an effective therapy that reduces the cost associated with OM treatment. However, little is known about its cost-effectiveness, mainly when quality of life is the effectiveness measure. Additionally, this therapy is not supported by the Brazilian public health system. Therefore, this study widens the knowledge about the safety of and strengthens evidence for the use of photobiomodulation therapy, providing information for public policy-makers and also for dental care professionals. This study is strongly encouraged due to its clinical relevance and the possibility of incorporating new technology into public health systems. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials-ReBEC, RBR-5h4y4n . Registered on 13 June 2017.

KRAS mutations drive adenomatoid odontogenic tumor and are independent of clinicopathological features.

Adenomatoid odontogenic tumor is a benign encapsulated epithelial odontogenic tumor that shows an indolent clinical behavior. We have reported in a few adenomatoid odontogenic tumors mutations in KRAS, which is a proto-oncogene frequently mutated in cancer such as lung, pancreas, and colorectal adenocarcinomas. We aimed to assess KRAS mutations in the hotspot codons 12, 13, and 61 in a large cohort of adenomatoid odontogenic tumors and to test the association of these mutations with clinical (age, site, tumor size, follicular/extrafollicular subtypes) and histopathological parameters. Thirty eight central cases were studied. KRAS codon 12 mutations were assessed by TaqMan allele-specific qPCR (p.G12V/R) and/or Sanger sequencing, and codon 13 and 61 mutations were screened by Sanger. Histological tumor capsule thickness was evaluated by morphometric analysis. Additionally, the phosphorylated form of the MAPK downstream effector ERK1/2 was investigated. Statistical analysis was carried out to test the association of KRAS mutations with clinicopathological parameters. KRAS c.35 G >T mutation, leading to p.G12V, was detected in 15 cases. A novel mutation in adenomatoid odontogenic tumor, c.34 G >C, leading to p.G12R, was detected in 12 cases and the other 11 were wild-type. Codon 12 mutations were not associated with the clinicopathological parameters tested. RAS mutations are known to activate the MAPK pathway, and we show that adenomatoid odontogenic tumors express phosphorylated ERK1/2. In conclusion, a high proportion of adenomatoid odontogenic tumors (27/38, 71%) have KRAS codon 12 mutations, which occur independently of the clinicopathological features evaluated. Collectively, these findings indicate that KRAS mutations and MAPK pathway activation are the common features of this tumor and some cancer types. Although it is unclear why different codon 12 alleles occur in different disease contexts and the complex interactions between tumor genotype and phenotype need clarification, on the basis of our results the presence of KRAS p.G12V/R favors the adenomatoid odontogenic tumor diagnosis in challenging oral neoplasm cases.