BackgroundOral peripheral nerve sheath tumors (OPNSTs) are reactive or neoplastic diseases that develop from proliferation of the nerve itself or their limiting sheaths. Here we describe the clinicopathologic data of OPNSTs observed in a sample of the Brazilian population and evaluate the expression of molecules associated with neural biology to determine their usefulness in the diagnosis.Material and MethodsDescriptive study of cases diagnosed as OPNSTs, from the Pathology Laboratory at the School of Dentistry/ Federal University of Uberlandia, followed by an immunohistochemical study of S-100, CD57, neurofilament protein (NFP) and epithelial membrane antigen (EMA).ResultsOPNSTs comprised 0.27% of all biopsies. There were eight patients with neurofibromas, eight with traumatic neuromas, seven with schwannomas, five with granular cell tumor (GCT), and four with palisaded encapsulated neuromas (PEN). Women were more frequently affected (60.6% of the cases). Tongue and lips prevailed as the most frequent sites. S-100 was reactive in 100% of the cases. Neural fibers evidenced by CD57 reactivity of their Schwann cells were always nested in bundles within neurofibromas and GCT, absent within schwannomas and dispersed within PEN. Reactivity for NFP was limited to axons and then followed the same pattern of CD57, though much less evident. Reactivity for EMA was observed in the capsular tissues and perineurium of nerve fascicles, and absent in parenchymal cells of GCT.ConclusionsThis study showed that OPNSTs are rare, widely benign and often found in tongue and lips. OPNSTs evolve from a common origin to distinct histological patterns, with eventual overlapping in their clinical and morphologic features. The arrangement of reactive residual neural fibers for CD57 can be a useful staining in the differential diagnosis of OPNSTs. Key words:Peripheral nerve sheath tumors. Oral cavity. Differential diagnosis. Immunohistochemistry. CD57 antigens.

Background The aim of this study was to describe the relative frequency and the main demographic and clinic-radiographic features related to patients diagnosed with Simple bone cyst (SBC) in an Oral Diagnosis Service in Southeast Brazil and present a review and discussion of international literature on this topic. Material and Methods SBC cases from our service encompassing the period between 1978 and 2017 were selected. In addition, a literature search was performed in the Pubmed/MEDLINE online electronic database published between 1951 and 2019. Results A total of 2,459 cystic lesions were documented in our service, thus 60 patients were diagnosed with the SBC representing 2.4% of all jaw cystic. Most of cases were asymptomatic. Multiple SBC lesions were seen in two patients (3.4%) and association with cemento-osseous dysplasia was seen in one female patient (1.7%). A total of 793 cases were enrolled in this literature review. Conclusions The SBC is an asymptomatic lesion often discovered in routine image exams in young patients. The unilocular, well defined margin with scalloped appearance is characteristic and helps the definition of diagnosis. This review suggests a different epidemiologic trend concerning to the sex and it confirms the posterior region of mandible as the more frequent location. The conservative treatment with limited exploration and curettage remains as the gold-standard treatment. Key words: Simple bone cyst, idiopathic bone cavity, traumatic bone cyst, conservative treatment.

Cholesterol granuloma (CG) is a tissue reaction in response to the accumulation of cholesterol crystals rarely found in the maxillary sinus. The etiopathogenesis of maxillary sinus CG remains unclear. We reviewed the literature and added two new reports of cholesterol granuloma in maxillary sinus related to endodontically treated maxillary posterior teeth. The first report refers to a 45-year-old woman diagnosed with rhinitis, who was submitted to endodontic retreatment of maxillary molar, and subsequently showed maxillary sinus opacity with cystic appearance. The second case describes a young adult woman, who presented a cystic mass in maxillary sinus after endodontic treatment, in close association with the apex of the maxillary right second premolar. Both patients were treated by a classic Caldwell-Luc surgery and the microscopic analyses revealed maxillary sinus CG. In the following, the authors discuss the probable involvement of endodontically treated maxillary posterior teeth in the etiopathogenesis of maxillary sinus CG.

Oral mucositis (OM) is a frequent and severe adverse effect of therapy against head and neck cancer. Photobiomodulation with the low-power laser is known to be effective against OM, but the diversity of protocols and the possibility of stimulating residual tumor cells are still obstacles. The present study aimed to compare two doses of laser energy delivered to the oral mucosa of patients under oncologic treatment for head and neck cancer, looking for differences in the control of mucositis, as well as in the frequency of tumoral recurrences. Fifty-eight patients undergoing radiotherapy were randomized into two groups, distinguished according to the energy delivered by laser irradiation, namely, 0.25 J and 1.0 J. The groups were compared according to frequency, severity, or duration of OM, as well as the frequency of tumoral recurrences. OM was significantly less frequent in patients receiving 1.0 J of energy, but the groups did not differ regarding severity or duration of OM. Tumoral recurrence also did not vary significantly between the groups. Photobiomodulation with a higher dose of energy (1.0 J versus 0.25 J) is associated with better control of radiotherapy-induced OM and does not significantly increase the risk of neoplastic recurrence.

Background. The present study aimed to investigate the clinical significance and prognostic value of the immunoexpression of cancer stem cell markers, ALDH1 and Notch1, in subtypes of oral squamous cell carcinoma. Materials and Methods. The expression of ALDH1 and Notch1 in 63 patients with well and poorly differentiated oral squamous cell carcinomas and their subtypes, verrucous carcinoma and basaloid squamous cell carcinoma, was evaluated by immunohistochemistry. The semi-quantitative analysis of the ALDH1 and Notch immunoexpression levels, based on the capture of 10 microscopic fields, at 400X magnification, at the invasive tumor front was performed and associated with clinicopathological variables using the chi-square test or Fisher’s exact test. The overall and disease-free survival rates were estimated according to the Kaplan–Meier method and the curves were compared using the log-rank test. The independent effects of variables were calculated using Cox’s proportional hazards regression model. Results. Strong ALDH1 and Notch1 expression was observed in 16 (25.4%) and 27 (42.9%) oral squamous cell carcinomas including their subtypes, respectively. Most tumors with strong immunoexpression of ALDH1 were basaloid squamous cell carcinoma (56.3%). Statistically significant associations were observed between the strong immunoexpression of Notch1 in poorly differentiated oral squamous cell carcinoma with perineural infiltration ( p  = 0.011) and lymph node involvement (pN+) ( p  = 0.034). The strong immunoexpression of ALDH1 was a prognostic factor associated with worse overall survival ( p  = 0.040) for patients with oral cancer. Conclusion. The strong immunoexpression of Notch1 can contribute to identification of patients with poorly differentiated oral squamous cell carcinoma, who have perineural infiltration or lymph node metastasis. In addition, the strong immunoexpression of ALDH1 may help to identify a worse prognosis in patients with oral squamous cell carcinoma and their subtypes.