Frequency of BRAF V600E immunoexpression in ameloblastomas: a multi-institutional analysis of 86 cases in Latin America and comprehensive review of the literature

BACKGROUND

The initiation of odontogenic tumorigenesis often involves the activation of the MAP-kinase pathway, with a pivotal role played by the BRAF V600E mutation. This study aimed to investigate the frequency of BRAF V600E immunoexpresion in ameloblastomas diagnosed in four Latin American centers and correlate this finding with the histological types and subtypes of the analyzed cases.

MATERIAL AND METHODS

A total of 86 samples of ameloblastomas were examined for immunohistochemistry using anti-BRAF V600E antibody. The histopathological features of each case were analyzed.

RESULTS

 Positivity for anti-BRAF V600E antibody was detected in 65/86 cases (75.6%). BRAF V600E was positive in 38/56 cases (67.9%) of conventional ameloblastomas and in 27/30 cases (90.0%) of unicystic ameloblastomas. A statistically significant difference in BRAF V600E positivity was observed when comparing unicystic ameloblastomas to conventional ameloblastomas (p=0.03). No statistically significant difference in BRAF V600E positivity was observed when comparing histological variants, both for conventional ameloblastomas and unicystic ameloblastomas.

CONCLUSIONS

This study highlights a high frequency of BRAF V600E immunoreactivity in ameloblastomas among Latin American cases. The prevalence of the BRAF V600E immunoexpresion may suggest the feasibility of utilizing BRAF-targeted therapy for ameloblastomas with this mutation.

Awareness on oral cancer among patients attending dental school clinics in Brazil

Background

Oral cancer is considered a public health problem worldwide. Dental schools may play an important role in educating patients about oral cancer. This study aimed at evaluating the knowledge of patients attending clinics at two dental schools in Brazil.

Material and Methods

From March 2017 to April 2017, 251 patients who were attending clinics at two dental schools in Recife, Brazil, were included in the study. Patients were contacted in the waiting rooms of the clinic. Each participant completed a self-administered questionnaire, which consists of 21 questions, including socio-demographic and specific information on the disease. Data were analyzed using descriptive statistics, and a chi-square test (with a 5% significance level) was used to assess the correlation between the variables, education and family income and other variables.

Results

Most participants were women (64.9%) with a mean age of 42.72 years. Most participants were knowledgeable about oral cancer and identified tobacco use (48.6%), alcohol consumption (25.1%), and solar radiation (12%) as the primary risk factors for the disease. Only 36.7% of the participants reported having received counselling on oral cancer, of which 18.3% received the information from a dentist. All patients with an income higher than six minimum wages were aware about oral cancer (p = 0.001).

Conclusions

These findings emphasize the importance of educational programs in dental schools as well providing integrated services for patients seeking care at school clinics, including population’s awareness on oral cancer.

Key words:Dental school, knowledge, oral cancer, oral health education, patient education.

[Hemostatic changes in children treated with heart surgery with cardiopulmonary bypass]

PURPOSE

We evaluated hemostasic changes in children undergoing open heart surgery with cardiopulmonary bypass (CPB).

METHODS

We studied 17 children before, during surgery, in the immediate, first and between the 4th and 7th postoperative days, measuring hematocrit, prothrombin time, activated partial thromboplastin time, fibrinogen, platelet count, factor V and euglobulin lysis time. Children were divided in those with and without excessive bleeding in the postoperative period.

RESULTS

We observed significant prolongation of prothrombin time and activated partial thromboplastin time, reduction of fibrinogen and factor V, and shortening of euglobulin lysis time. Six (35%) children bled excessively. Platelet count reduction was greater in the intra operative period in these cases and the duration of CPB was longer in this group.

CONCLUSION

Changes in hemostasis during open heart surgery are due to coagulation cascade disorders as well as fibrinolysis. The incidence of excessive bleeding is higher in the pediatric group. Prolonged CPB time and greater reduction in platelet count differentiated both groups.