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A common mutation in the BRAF gene, comprising the T1799A nucleotide transversion, which leads to the V600E amino acid substitution in the BRAF protein, has been observed in about 50% of papillary thyroid carcinomas (PTCs). However, BRAF protein expression has been rarely examined in such tumors. Clinical studies have shown important associations between BRAF mutation and clinical parameters in PTC, such as progression, invasion, and recurrence. The aim of this study was to evaluate the association between BRAF protein overexpression and the BRAF V600E mutation in a group of PTC patients. The study group included 116 patients with PTC from Araújo Jorge Hospital, Goiânia, Goiás, Brazil. Immunohistochemistry was utilized to analyze BRAF protein expression. Presence of the BRAF V600E mutation was determined by polymerase chain reaction amplification and restriction fragment length polymorphism, and confirmed by direct sequencing. The chi-square test with Yates correction and the Fisher exact test were used for statistical analysis. BRAF overexpression was detected in 55 patients with PTC (47.4%) and the BRAF V600E mutation was observed in 74 patients (63.8%). In the studied group, significant associations were observed between the BRAF V600E mutation and BRAF protein overexpression (P = 0.0115), and also between BRAF overexpression and extra-thyroid extension of the tumor (P = 0.0111). This study demonstrated a significant association between BRAF overexpression and the BRAF V600E mutation in PTC, highlighting the importance of these molecular events in the process of PTC carcinogenesis.

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer and can present as lymph node metastasis in 30 to 65% of cases when initially diagnosed. High frequency recurrence, distant metastasis and treatment resistance can be found in cases of PTC so early diagnosis and treatment are critical for improved prognosis and better survival rates. The characterization of new biomarkers has proved useful for the diagnosis and follow-up of these patients. HLA-G is a non-classical HLA class I molecule whose expression in cancer cells has been associated with tumor evasion of immune response. Therefore, the aim of this study was to investigate the HLA-G expression and its clinical significance in PTC. Paraffin-embedded thyroid biopsies of 70 PTC patients (40 of whom had presented with metastasis) were evaluated. HLA-G-staining was observed in tumor cells in PTC, and the HLA-G expression was significantly associated with an increased occurrence of lymph node metastasis (p=0.0006) and capsular invasion (p=0.02). This preliminary data shows the HLA-G expression in thyroid carcinoma specimens for the first time and suggests that this expression could impair efficient anti-tumor immunity in PTC. This would indicate that HLA-G could have an independent prognostic value in PTC, principally for tumor recurrence., (Copyright © 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Background: Leiomyosarcoma is a malignant tumor that originates in smooth muscle cells and is rarely found in the oral cavity. We present a case of high-grade primary leiomyosarcoma in the mandible and discuss the diagnosis process., Methods: The patient was a 64-year-old white man who had a slight increase in volume in the left-side mandible with a radiolucent osteolytic image with the destruction of the mandibular cortex. Incisional biopsy and preoperative examination were performed, including cone beam CT and examination by immunohistochemistry that defined the histologic diagnosis of leiomyosarcoma. The patient underwent reconstruction with an osteocutaneous flap with microvascular anastomosis., Results: Two years after the surgery, there was no sign of recurrence of the lesion., Conclusion: The use of cone beam CT to define the limits of the lesion and the immunohistochemical findings were essential to establish the treatment plan., (Copyright © 2011 Wiley Periodicals, Inc.)

Nevoid cell carcinoma syndrome or Gorlin-Goltz syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinoma, multiple keratocyst tumors, and skeletal anomalies. The Gorlin-Goltz syndrome has been associated with numerous benign and malignant neoplasms. The authors describe a case of Gorlin-Goltz syndrome in association with non-Hodgkin's lymphoma. To the best of our knowledge, this is the second case described in the English literature.

Burkitt's lymphoma is not an uncommon malignancy in the paediatric population. It is a high-grade non-Hodgkin B-cell lymphoma which may present as endemic, sporadic and human immunodeficiency-associated subtypes. The African, or endemic, variant usually involves the maxilla and other facial bones while head and neck manifestations in sporadic Burkitt's lymphoma are rare. We described a case of oral Burkitt's lymphoma involving the right jaw in a 4-year-old boy. The patient presented with a rapidly-enlarging swelling of one month duration, toothache-like pain and radiographical appearance of 'floating teeth' in the right mandible. Incisional biopsy revealed small round tumour cells with scarce cytoplasm and multiple small nuclei interspersed by phagocytic macrophages. The tumour cells were immunopositivity for CD20 and CD10, expressed weak positivity for CD3, negative for CD5 and showed > 90% positivity for Ki-67. Tumour remission was achieved with six cycles of chemotherapy with the CHOP regime.