Roberto Almeida de Azevedo

Transcriptional profiles of SHH pathway genes in keratocystic odontogenic tumor and ameloblastoma

BACKGROUND Sonic hedgehog (SHH) pathway activation has been identified as a key factor in the development of many types of tumors, including odontogenic tumors. Our study examined the expression of genes in the SHH pathway to characterize their roles in the pathogenesis of keratocystic odontogenic tumors (KOT) and ameloblastomas (AB). METHODS We quantified the expression of SHH, SMO, PTCH1, SUFU, GLI1, CCND1, and BCL2 genes by qPCR in a total of 23 KOT, 11 AB, and three non-neoplastic oral mucosa (NNM). We also measured the expression of proteins related to this pathway (CCND1 and BCL2) by immunohistochemistry. RESULTS We observed overexpression of SMO, PTCH1, GLI1, and CCND1 genes in both KOT (23/23) and AB (11/11). However, we did not detect expression of the SHH gene in 21/23 KOT and 10/11 AB tumors. Low levels of the SUFU gene were expressed in KOT (P = 0.0199) and AB (P = 0.0127) relative to the NNM. Recurrent KOT exhibited high levels of SMO (P = 0.035), PTCH1 (P = 0.048), CCND1 (P = 0.048), and BCL2 (P = 0.045) transcripts. Using immunolabeling of CCND1, we observed no statistical difference between primary and recurrent KOT (P = 0.8815), sporadic and NBCCS-KOT (P = 0.7688), and unicystic and solid AB (P = 0.7521). CONCLUSIONS Overexpression of upstream (PTCH1 and SMO) and downstream (GLI1, CCND1 and BCL2) genes in the SHH pathway leads to the constitutive activation of this pathway in KOT and AB and may suggest a mechanism for the development of these types of tumors.

Keratocystic odontogenic tumour: an experience in the Northeast of Brazil.

INTRODUCTION Keratocystic odontogenic tumours raise particular interest, because of their high recurrence rate and association with nevoid basal cell carcinoma syndrome. OBJECTIVE To analyze the clinical and histopathological features of all cases diagnosed as keratocystic odontogenic tumour in a Brazilian population. METHODS A total of 64 keratocystic odontogenic tumours, arising in forty-six patients, were evaluated using the following parameters: association with nevoid basal cell carcinoma syndrome, gender, age at first diagnosis, race, anatomical location, symptoms, radiographic features, history of recurrence, association with teeth, and treatment. RESULTS Keratocystic odontogenic tumours were more frequent among women than men (1:0.84). The mean patient age was 31.5 years (SD: +/- 16.6). Ten tumours (16.4%) involved the maxilla and 51 (83.6%) the mandible. Swelling (n = 12; 46.1%), followed by pain and swelling (n = 4; 15.3%), were most common clinical manifestations. A unilocular radiotransparency with well-defined margins was the main radiographic finding (n = 29; 87.8%). A significant association was observed between the multilocular radiographic pattern and recurrence (p < 0.05, Fishers Test). Sixty-one (95.3%) tumours were treated by surgical enucleation followed by bone curettage, and the recurrence rate was 13% (n = 6). This study showed that the keratocystic odontogenic tumours relapsed within a mean period of 25-36 months. CONCLUSION Despite the results of this study being similar to previous reports found in the literature, it provides an important insight about keratocystic odontogenic tumours in a Brazilian population.

Oral findings in patients with mucolipidosis type III

Mucolipidosis type III is a rare, autosomal recessive disorder, which is part of a group of storage diseases as a result of inborn error of lysosomal enzyme metabolism. It is characterized by the gradual onset of signs and symptoms affecting the physical and mental development as well as visual changes, heart, skeletal and joint. Although oral findings associated with mucolipidosis type II have been extensively reported, there is a shortage of information on mucolipidosis type III. This paper presents radiological and histological findings of multiple radiolucent lesions associated with impacted teeth in the jaw of a 16 year-old youngster with mucolipidosis type III.

Assessment of computerized tomography density patterns of ameloblastomas and keratocystic odontogenic tumors

The aim of this study was to evaluate computerized tomography (CT) density patterns of solid ameloblastomas (SA), unicystic ameloblastomas (UA), and sporadic and multiple keratocystic odontogenic tumors (SK and MK, respectively). A region of interest (ROI) was delimited corresponding to almost the entire lesional area on each axial slice of 25 CT exams. For each ROI, CT values (HU(ROI)) and heterogeneity (HTG(ROI)) were recorded and compared among lesion groups as well as among central and peripheral slices of the same lesion. The average HU(ROI) were: SA 35.9 +/- 12.6; UA 31.0 +/- 6.0; SK 28.4 +/- 10.5; and MK 30.5 +/- 20.6. SK and MK had the lowest CT values and highest heterogeneity. SA and UA did not show statistical difference for HU(ROI). However, SA had greater HTG(ROI) values. SA presented a different pattern when the central slices were compared with the peripheral slices. HU(ROI) was higher, whereas HTG(ROI) was lower, among the central slices of SA.

Clinicopathological and demographic characteristics of ameloblastomas in a population from Bahia, Brazil

Purpose: The present study aimed to review a series of ameloblastoma cases by observing their clinicopathological and demographic characteristics. The data in this study were compared to previous studies. Methods: Seventy ameloblastoma cases were obtained from the archive of the Surgical Pathology Service of the Dental School of the Federal University of Bahia and were analyzed with regards to age, gender, clinical manifestation, radiographic aspect, anatomical distribution and histological subtype. These data were submitted to statistical analysis. Results: Of the 70 cases, 35 (50%) occurred in males and 35 (50%) in females. Young adults were most affected by tumors. Fifty-six (80%) of all tumor cases occurred in the jaw. The main histological subtype seen was unicystic ameloblastoma, which occurred in 35 cases. The majority of the tumors [n=57 (81.4%)] were treated with radical surgery. The differences in clinical aspects and anatomical distribution were shown to be statistically significant (P < 0.001). Conclusion: The clinical-epidemiological profile of the patients in the present study is similar to that in other populations, with unicystic ameloblastoma being the most common histological subtype seen.

Total bilateral TMJ reconstruction for pain and dysfunction: Case report

Highlights • The use of TMJ protheses was configured as a good therapeutic alternative for severe conditions that do not respond to conservative treatments.• A correct diagnosis of the pathology and the correct indication for reconstruction are fundamental for the success of the technique.• The stock prostheses is a good alternative when there is no need for mandibular advancement and the branches are still preserved.• Further studies are needed to demonstrate whether these results are long term.

Ameloblastoma with adenoid features: A series of eight cases

BACKGROUND Ameloblastoma with adenoid features are characterized by the presence of duct-like structures formed from the parenchyma of the tumor. This study was conducted to report a series of eight ameloblastomas with adenoid features, highlighting their clinicopathological and immunohistochemical aspects. MATERIAL AND METHODS Out of 71 cases of ameloblastomas, this study classified 8 cases as ameloblastomas with adenoid features. Clinicopathological data and immunohistochemistry for CK7, CK14, CK19, IMP3, p53 and Ki-67 were evaluated. RESULTS From those cases of ameloblastoma exhibiting adenoid features, there were 4 women and 4 men, with mean age of 39 years. Most cases affected the mandible and all presented radiographically as a radiolucency. The predominant histopathological features were pseudoducts, squamous metaplasia, nuclear hyperchromatism, clear cells, whorled aspect of epithelial structures, cribriform growth pattern, proliferation of spindle cells and extracellular eosinophilic material. Immunohistochemical analysis showed high expression for CK14 (n = 6) and CK19 (n = 3) and all cases (n = 8) were negative for p53, IMP3 and CK7. In addition, all samples (n = 8) showed low expression for Ki-67. CONCLUSIONS The similarities between the histopathological and immunohistochemical features of eight cases described in the present study and those described in previous studies support the possibility that these lesions are adenoid ameloblastomas. In addition, the immunohistochemical results of CK14, CK19, p53 and Ki-67 did not differ from those of conventional ameloblastomas.

Appositional bone graft tunneled: Technical note

Highlights • The tunnel technique for onlay bone grafting is a simple and easy to perform technique.• We had no implant loss with the tunnel technique in the onlay bone graft.• The fact that the periosteum is kept intact, is a crucial element for the survival and viability of the graft block.

An unusual pleomorphic adenoma

O adenoma pleomorfico e a neoplasia mais comum entre os tumores das glândulas salivares maiores e menores. Constitui aproximadamente 90% de todas as lesoes benignas das glândulas salivares e a parotida e a mais acometida. A juncao dos palatos duro e mole e o sitio de predilecao mais comum, quando as glândulas salivares menores sao atingidas. O diagnostico e complexo devido a grande variedade histologica e comportamento biologico deste tumor, sendo imprescindivel a realizacao do estudo histopatologico. O tratamento de escolha e a excisao cirurgica. Para as lesoes localizadas no lobo superficial da parotida e recomendada a parotidectomia superficial com a identificacao e preservacao do nervo facial. As lesoes do palato ou gengiva por vezes podem exigir margem de seguranca, sendo geralmente excisadas abaixo do periosteo, incluindo a mucosa sobrejacente. Com a remocao cirurgica adequada, o prognostico e excelente. O presente trabalho tem como objetivo relatar um caso de adenoma pleomorfico nao usual de glândula salivar menor no palato duro, em regiao posterior direita, alem de descrever os aspectos mais importantes dessa patologia.