Atypical cellular neurothekeoma of the oral mucosa: A rare case report and literature review.

Cellular neurothekeoma (CN) is a benign dermal neoplasm that most often affects the head and neck region and rarely occurs in the oral mucosa. We report a rare case of CN with atypical features on the floor of the mouth and summarize the reported cases of oral CN in English-language literature. A 62-year-old woman presented with a 6-month history of a painless mass on the floor of the mouth. Histopathological analysis of the excised specimen revealed a proliferation of neoplastic cells with oval to spindle morphology arranged in a vaguely nested and multinodular architecture separated by scarce hyaline collagen within a predominantly myxoid-rich stroma. The tumor cells were positive for NSE, and CD63 (NKI/C3), and negative for S100 protein, CD34, and SMA. Thus, the final diagnosis was CN. In addition, we summarized all clinicopathological data on oral CNs reported in the English-language literature. Nineteen cases were reviewed. Among them, only one case affected the floor of the mouth of a young girl, in contrast to the present case that occurred in an elderly woman. CN is particularly rare in this location and may be a diagnostic challenge for oral pathologists due to its rarity and morphological similarity with other lesions.

The impact of radiation caries on morbidity and mortality outcomes of head and neck squamous cell carcinoma patients.

AIMS: Radiation caries (RC) is a highly prevalent and chronic complication of head and neck radiotherapy (HNRT) and presents a challenge for clinicians and patients. The present study aimed to assess the impact of RC on the morbidity and mortality outcomes of head and neck squamous cell carcinoma (HNSCC) patients. METHODS AND RESULTS: Patients were divided into three groups: (1) RC (n = 20), (2) control (n = 20), and (3) edentulous (n = 20). Information regarding the number of appointments, dental procedures, osteoradionecrosis (ORN), prescriptions, and hospital admissions were collected. Mortality outcomes were assessed through disease-free survival (DFS) and overall survival (OS) rates. RC patients required more dental appointments (p < .001), restorations (p < .001), extractions (p = .001), and antibiotic and analgesic prescriptions (p < .001). Kaplan-Meier subgroup analyses showed a significantly increased risk of ORN in RC compared to edentulous patients (p = .015). RC patients presented lower DFS rates (43.2 months) than the control and edentulous groups (55.4 and 56.1 months, respectively). CONCLUSIONS: RC impacts morbidity outcomes among cancer survivors due to increased demand for medication prescriptions, multiple specialized dental appointments, invasive surgical treatments, increased risk of ORN, and increased need for hospital admissions.

Human Papillomavirus-Associated Oral Epithelial Dysplasia: Report of 5 Illustrative Cases from Latin America.

BACKGROUND: Human papillomavirus-associated oral epithelial dysplasia (HPV-OED) is a distinct oral epithelial disorder characterized by viral cytopathic changes caused by transcriptionally active high-risk HPV. The aim of the present study was to report 5 additional cases from Latin America. METHODS: Clinical data from five patients with HPV-OED were obtained from the archives of three oral pathology services from Brazil and Chile. All cases were submitted to morphological, p16 expression and in situ hybridization (ISH) for HPV analyses. RESULTS: Four patients were male and one patient was female, with a mean age of 55.4 years. Four patients were HIV seropositive and two were smokers. Three cases affected the buccal mucosa and commissure, one of which had an additional plaque in the soft palate, and one case each occurred on the floor of mouth and lower labial mucosa. Most cases presented as well-demarcated white plaques with a verrucous surface. One case presented multiple lesions ranging from normal to white-colored slightly elevated plaques with a cobblestone surface. Peripheral mucosal pigmentation was observed in two cases. All five cases presented with the characteristic microscopic features of HPV-OED, including severe dysplasia with numerous karyorrhectic and apoptotic cells, full-thickness "block positivity" for p16 and high Ki-67 index (> 90%) sharply demarcated from the adjacent non-dysplastic epithelium. Wide-spectrum DNA ISH-HPV was positive in 4 cases. All patients were treated with conservative surgical excision with no signs of recurrence after a mean of 39-month follow-up. CONCLUSION: This represents the first series of HPV-OED from Latin America; most cases presented as well-demarcated papillary white plaques affecting the buccal mucosa and commissure of HIV-positive middle-aged men, two of them exhibiting peripheral pigmentation caused by reactive melanocytes. The typical microscopic findings of HPV-OED were observed in all cases, which also showed strong p16 positivity in a continuous band through the full thickness of the epithelium and high Ki67.

The use of deep learning state-of-the-art architectures for oral epithelial dysplasia grading: A comparative appraisal.

BACKGROUND: Dysplasia grading systems for oral epithelial dysplasia are a source of disagreement among pathologists. Therefore, machine learning approaches are being developed to mitigate this issue. METHODS: This cross-sectional study included a cohort of 82 patients with oral potentially malignant disorders and correspondent 98 hematoxylin and eosin-stained whole slide images with biopsied-proven dysplasia. All whole-slide images were manually annotated based on the binary system for oral epithelial dysplasia. The annotated regions of interest were segmented and fragmented into small patches and non-randomly sampled into training/validation and test subsets. The training/validation data were color augmented, resulting in a total of 81,786 patches for training. The held-out independent test set enrolled a total of 4,486 patches. Seven state-of-the-art convolutional neural networks were trained, validated, and tested with the same dataset. RESULTS: The models presented a high learning rate, yet very low generalization potential. At the model development, VGG16 performed the best, but with massive overfitting. In the test set, VGG16 presented the best accuracy, sensitivity, specificity, and area under the curve (62%, 62%, 66%, and 65%, respectively), associated with the higher loss among all Convolutional Neural Networks (CNNs) tested. EfficientB0 has comparable metrics and the lowest loss among all convolutional neural networks, being a great candidate for further studies. CONCLUSION: The models were not able to generalize enough to be applied in real-life datasets due to an overlapping of features between the two classes (i.e., high risk and low risk of malignization).

Rhabdomyosarcoma with TFCP2 Rearrangement or Typical Co-expression of AE1/AE3 and ALK: Report of Three New Cases in the Head and Neck Region and Literature Review.

BACKGROUND: Rhabdomyosarcoma (RMS) harboring EWSR1/FUS-TFCP2 fusions has been recently described as a distinct form of RMS with an aggressive course and predilection for the craniofacial bones, especially the jaws. METHODS: We report three new cases of this rare entity, two from Brazil and one from Guatemala, with detailed clinicopathologic, immunohistochemical, and molecular descriptions. Additionally, we explored the English-language literature searching RMS with TFCP2 rearrangement or typical immunophenotype with co-expression of AE1/AE3 and ALK in the head and neck region. RESULTS: Case 1 is a 58-year-old male with a 3-month history of painful swelling in the anterior maxilla. Case 2 is a 22-year-old male presenting with right facial swelling and proptosis. Case 3 is a 43-year-old female with a rapidly growing tumor located in the zygomatic region. Imaging examinations revealed highly destructive intraosseous masses in the first two cases, and a soft tissue tumor with bone invasion in case 3. Microscopically, all cases showed a hybrid spindle and epithelioid phenotype of tumor cells which expressed desmin, myogenin and/or Myo-D1, AE1/AE3, and ALK. FISH confirmed molecular alterations related to TFCP2 rearrangement in Cases 1-2. In case 3, there was no available material for molecular analysis. The patients were subsequently referred to oncologic treatment. Additionally, we summarized the clinicopathologic, immunohistochemical, and molecular features of 27 cases of this rare RMS variant in the head and neck region reported in the English-language literature. CONCLUSION: RMS with TFCP2 rearrangement is a rare and aggressive tumor with a particular predilection for craniofacial bones, especially the jaws. Knowing its clinicopathologic and immunohistochemical profile can avoid misdiagnosis.

Prognostic outcomes of oral squamous cell carcinoma derived from proliferative verrucous leukoplakia: A systematic review.

OBJECTIVE: This study aimed to evaluate prognostic outcomes of PVL-derived oral squamous cell carcinomas (P-OSCC) based on recurrence, new primary tumour, metastasis and survival information. STUDY DESIGN: Five databases and grey literature were searched electronically with the following main keywords (proliferative verrucous leukoplakia, squamous cell carcinoma and malignant transformation) to answer the following review question: 'Are survival outcomes for P-OSCC worse?' based on the PECOS principle. The Joanna Briggs Institute Critical Appraisal tool was used to identify possible biases and assess the quality of each of the primary studies. RESULTS: A total of 21 articles met the inclusion criteria, and the results of this systematic review suggest that P-OSCC can recur and generate new primary tumours; however, metastases are rare. Thus, most patients remain alive for an average period of 5 years. CONCLUSION: Apparently, P-OSCC has better clinical prognostic characteristics than conventional OSCC. There is a lack of information on the main prognostic outcomes of P-OSCC; therefore, specific studies must be performed to achieve a better comparison between P-OSCC and conventional OSCC progression.

Discovery proteomics reveals potential protein signature associated with malignant phenotype acquisition in pleomorphic adenoma.

OBJECTIVE: To analyze the proteomic profile of salivary pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma (CXPA) samples and correlate them with the malignant transformation of the PA. MATERIALS AND METHODS: Thirty samples (10 PA, 16 CXPA, and 4 residual PA) were microdissected and submitted to liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proteomic data and protein identification were analyzed through LC-MS/MS spectra using the MaxQuant software. RESULTS: The proteomic analysis identified and quantified a total of 240 proteins in which 135 were found in PA, residual PA, and CXPA. The shared proteins were divided into six subgroups, and the proteins that showed statistically significant differences (p > 0.05) and fold-change > or <2.5 in one subgroup to another subgroup were included. Seven proteins (Apolipoprotein A-I-APOA1, haptoglobin-HP, protein of the synaptonemal complex 1-SYCP1, anion transport protein of band 3-SLC4A1, subunit µ1 of AP-1 complex-AP1M1, beta subunit of hemoglobin-HBB, and dermcidin-DCD) were classified as potential protein signatures, being HP, AP1M1, and HBB with higher abundance for PA to residual PA, APOA1 with higher abundance for PA to CXPA, SLC4A1 with lower abundance in the PA to CXPA, SYCP1with lower abundance for residual PA to CXPA, and DCD with higher abundance in the CXPA with epithelial differentiation to myoepithelial differentiation. CONCLUSIONS: In this work, we demonstrated the comparative proteomic profiling of PA, residual PA, and CXPA, and seven were proposed as protein signatures, some of which may be associated with the malignant phenotype acquisition.

FGFR1 is an important prognostic factor in oral leukoplakia and tongue squamous cell carcinoma.

BACKGROUND: Fibroblast growth factor receptor 1 is a potential prognostic factor for tongue squamous cell carcinoma and is associated with oral epithelial dysplasia grade in oral leukoplakia. METHODS: Thirty cases of tongue squamous cell carcinoma and 30 cases of oral leukoplakia were analyzed. Fibroblast growth factor receptor 1 and phosphorylated Akt protein expression were analyzed by immunohistochemistry and quantified using a digital algorithm. Fibroblast growth factor receptor 1 gene amplification was analyzed by fluorescent in situ hybridization in the tongue squamous cell carcinoma cases. RESULTS: Clinical appearance and dysplasia grade were correlated with oral leukoplakia malignant transformation. Oral leukoplakia cases presenting high fibroblast growth factor receptor 1 expression showed a higher risk of malignant transformation (p = 0.016, HR: 7.3, 95% CI: 1.4-37.4). Phosphorylated Akt showed faint to no expression in oral leukoplakia, which did not correlate with dysplasia grade or malignant transformation. High expression of fibroblast growth factor receptor 1 and phosohorylated Akt were associated with poor overall survival and disease-free survival in tongue squamous cell carcinoma, although only fibroblast growth factor receptor 1 expression was significantly associated with poor overall survival (p = 0.024; HR: 4.9, 95% CI: 1.2-19.9). Cases presenting double fibroblast growth factor receptor 1/phosphorylated Akt overexpression (n = 8) showed markedly impaired overall survival (p = 0.020; HR: 6.4, 95% CI: 1.3-31.1) and disease-free survival (p = 0.001, HR: 13.0, 95% CI: 3.0-55.7). Fibroblast growth factor receptor 1 amplification was observed in 16.6% of tongue squamous cell carcinoma cases, being correlated with vascular and neural invasion (p = 0.001 and 0.017, respectively), but not with fibroblast growth factor receptor 1 protein expression, overall survival, or disease-free survival. CONCLUSION: Fibroblast growth factor receptor 1 protein expression is an important prognostic factor in oral leukoplakia and tongue squamous cell carcinoma.

Hybrid Neurofibroma/Schwannoma of the Oral Cavity: A Rare Case Report and Literature Review.

Hybrid peripheral nerve sheath tumors show combined features of more than one type of conventional benign peripheral nerve sheath tumors. There are few cases reported of hybrid peripheral nerve sheath tumors in the head and neck region. A 68-year-old female patient was referred for evaluation of an oral swelling lasting five years. Intraoral examination revealed a small mobile nodule located in the lower vestibule. The patient underwent excisional biopsy and microscopic evaluation showed typical features of neurofibroma enclosing areas with palisading nuclei compatible with Antoni A pattern, which are seen in schwannomas. These regions showed strong and diffuse immunoreactivity for S100 protein and moderate positivity in the neurofibroma area. CD34 was positive in the neurofibroma area and entrapped axons were positive for neurofilament. The final diagnosis was oral hybrid neurofibroma-schwannoma tumor. Hybrid peripheral nerve sheath tumors, although extremely rare, may arise within the oral cavity. To the best of our knowledge, this is the first neurofibroma-schwannoma tumor reported in the oral cavity. Recognizing hybrid peripheral nerve sheath tumors as a distinct clinicopathological entity is important because they may also be associated with syndromic disorders.

Actinomycotic Osteomyelitis and Myiasis in Oroantral Communication: Clinicopathological and Tomographic Findings

Actinomycotic osteomyelitis of the maxilla presenting with oroantral communication is very rare, herein we report the first case of this condition in association with myiasis. A 50-year-old man reported chronic sinusopathy and a non-healing maxillary lesion, with 30 years of evolution, presenting occasional nasal and intraoral purulent discharge, with foul smell, and recurrent episodes of larvae presence. Cone beam computed tomography showed a large hyperdense image inside the left maxillary sinus, with focal areas with soft tissue density, and extensive discontinuity of the maxillary sinus floor, confirming the oroantral fistula. The necrotic tissue curetted during surgery presented hard consistency, and dark greenish color, and was submitted for histopathological analysis. Microscopically, necrotic bone, masses of filamentous bacteria colonie s, compatible with actinomycosis, and large rhomboidal structures surrounded by eosinophilic capsule - suggestive of larvae, were observed. The diagnosis of actinomycotic osteomyelitis with presence of structures compatible with larvae was established.

La osteomielitis actinomicótica del maxilar que se presenta con comunicación oroantral es poco frequente. En este trabajo reportamos el primer caso de esta condición en asociación con miasis. Un hombre de 50 años que refiere sinusopatía crónica y lesión maxilar que no cicatriza, de 30 años de evolución, presenta secreción ocasional purulenta nasal e intraoral, con mal olor y episodios recurrentes de presencia de larvas. La tomografía computarizada de haz cónico mostró una gran imagen hiperdensa en el interior del seno maxilar izquierdo, con áreas focales con densidad de partes blandas y una extensa discontinuidad del piso del seno maxilar, lo que confirma la fístula oroantral. El tejido necrótico legrado durante la cirugía presentó consistencia dura, coloración verdosa oscura, y fue remitido para análisis histopatológico. Microscópicamente se observó hueso necrótico, masas de colonias de bacterias filamentosas compatibles con actinomicosis y grandes estructuras romboidales rodeadas de cápsula eosinofílica sugestiva de larvas. Se estableció el diagnóstico de osteomielitis actinomicótica con presencia de estructuras compatibles con larvas.

A Rare Case of Mandibular Aspergillus Osteomyelitis in an Immunocompetent Patient.

Aspergillosis is a fungal infection caused by Aspergillus species, which is contracted through spores that colonize the respiratory tract, causing rhinosinusitis and pulmonary infections. Oral aspergillosis is rare and, when present, may cause soft tissue and bone destruction, generally in immunodeficient patients. Mandibular Aspergillus osteomyelitis is even rarer, with few cases reported in the literature. A 57-year-old Caucasian woman was referred for the evaluation of painful recurrent swelling in the anterior mandibular alveolar ridge, with purulent drainage, previously treated with multiple surgical debridement procedures and antibiotics without success. The patient was otherwise systemically healthy. Surgical debridement was performed and histopathological examination showed osteomyelitis associated with Aspergillus species. Therapy with oral itraconazole (400 mg per day) was administered for 3 months, resulting in complete resolution. No recurrence was detected after 15 years of follow-up. The patient was rehabilitated with dental implants. In conclusion, non-bacterial microorganisms, such as Aspergillus, should be considered in cases of mandibular osteomyelitis that do not heal after surgical debridement and antibiotic therapy.

Heparanase 1 Upregulation Promotes Tumor Progression and Is a Predictor of Low Survival for Oral Cancer.

Background: Oral cavity cancer is still an important public health problem throughout the world. Oral squamous cell carcinomas (OSCCs) can be quite aggressive and metastatic, with a low survival rate and poor prognosis. However, this is usually related to the clinical stage and histological grade, and molecular prognostic markers for clinical practice are yet to be defined. Heparanase (HPSE1) is an endoglycosidase associated with extracellular matrix remodeling, and although involved in several malignancies, the clinical implications of HPSE1 expression in OSCCs are still unknown. Methods: We sought to investigate HPSE1 expression in a series of primary OSCCs and further explore whether its overexpression plays a relevant role in OSCC tumorigenesis. mRNA and protein expression analyses were performed in OSCC tissue samples and cell lines. A loss-of-function strategy using shRNA and a gain-of-function strategy using an ORF vector targeting HPSE1 were employed to investigate the endogenous modulation of HPSE1 and its effects on proliferation, apoptosis, adhesion, epithelial-mesenchymal transition (EMT), angiogenesis, migration, and invasion of oral cancer in vitro. Results: We demonstrated that HPSE1 is frequently upregulated in OSCC samples and cell lines and is an unfavorable prognostic indicator of disease-specific survival when combined with advanced pT stages. Moreover, abrogation of HPSE1 in OSCC cells significantly promoted apoptosis and inhibited proliferation, migration, invasion, and epithelial-mesenchymal transition by significantly decreasing the expression of N-cadherin and vimentin. Furthermore, a conditioned medium of HPSE1-downregulated cells resulted in reduced vascular endothelial growth. Conclusion: Our results confirm the overexpression of HPSE1 in OSCCs, suggest that HPSE1 expression correlates with disease progression as it is associated with several important biological processes for oral tumorigenesis, and can be managed as a prognostic marker for patients with OSCC.

Spindle cell carcinoma of the lip: An immunohistochemical study of a challenging case.

INTRODUCTION: Spindle cell carcinoma (SpCC) or sarcomatoid carcinoma, is a rare variant of squamous cell carcinoma (SCC) that has a variable proportion of carcinomatous and sarcomatous components. Here, we reported an immunohistochemical study of a spindle cell carcinoma with a challenging morphological diagnosis. CASE REPORT: A 50-year-old woman with a previous history of nodular melanoma was referred for evaluation of a painful papule in the lower lip. After surgical resection, neoplastic cells showed focal positivity for CK-14, αSMA, p63, and confirmed the strong positivity for S100 and vimentin. Tumor cells were negative for HMB-45, Melan A, SOX-10, AE1/AE3, 34ßE12, CK5-6, CAM5.2, EMA, desmin, calponin, CD10, CD34, and CD68. With these findings, a diagnosis of SpCC was rendered. The patient presented lung and dorsal metastases after 12 months and after 3 years of follow-up, the patient died. CONCLUSION: In summary, a careful correlation of microscopy and immunohistochemical characteristics is required for the proper diagnosis of this lesion.

The role of osteopontin in oral cancer: A brief review with emphasis on clinical applications.

Osteopontin (OPN) is a calcium-binding glycol-phosphoprotein present in many physiologic and pathological processes. This protein can control bone cell adhesion, osteoclastic activity, and bone matrix mineralization. However, its participation in pathological processes such as atherosclerosis, sarcoidosis, tuberculosis, and cancer have been described. Some studies have shown that OPN may participate in the development and progression of oral cancer. Although the role of OPN in oral cancer is not fully understood, some studies have suggested that this protein may induce malignant phenotype of cells by activation of PI3K/AKT/mTOR pathway, which favors cell proliferation, invasion, metastasis, angiogenesis, and failure of treatment. This review discusses the possible mechanism of involvement of OPN in oral cancer and its potential clinical application in diagnosis and prognosis.

Polypodium leucotomos targets multiple aspects of oral carcinogenesis and it is a potential antitumor phytotherapy against tongue cancer growth.

Introduction: Oral cancer refers to malignant tumors, of which 90% are squamous cell carcinomas (OSCCs). These malignancies exhibit rapid progression, poor prognosis, and often mutilating therapeutical approaches. The determination of a prophylactic and/or therapeutic antitumor role of the polyphenolic extract Polypodium leucotomos(PL) would be relevant in developing new tools for prevention and treatment. Methods: We aimed to determine the antitumor effect of PL by treating OSCC cell lines with PL metabolites and evaluating its action during OSCC progression in vivo. Results: PL treatment successfully impaired cell cycling and proliferation, migration, and invasion, enhanced apoptosis, and modulated macrophage polarization associated with the tumoral immune-inflammatory response of tongue cancer cell lines (TSCC). PL treatment significantly decreased the expression of MMP1 (p < 0.01) and MMP2 (p < 0.001), and increased the expression of TIMP1 (p < 0.001) and TIMP2 (p < 0.0001) in these cells. The mesenchymal-epithelial transition phenotype was promoted in cells treated with PL, through upregulation of E-CAD (p < 0.001) and reduction of N-CAD (p < 0.05). PL restrained OSCC progression in vivo by inhibiting tumor volume growth and decreasing the number of severe dysplasia lesions and squamous cell carcinomas. Ki-67 was significantly higher expressed in tongue tissues of animals not treated with PL(p < 0.05), and a notable reduction in Bcl2 (p < 0.05) and Pcna (p < 0.05) cell proliferation-associated genes was found in dysplastic lesions and TSCCs of PL-treated mice. Finally, N-cad(Cdh2), Vim, and Twist were significantly reduced in tongue tissues treated with PL. Conclusion: PL significantly decreased OSCC carcinogenic processes in vitro and inhibited tumor progression in vivo. PL also appears to contribute to the modulation of immune-inflammatory oral tumor-associated responses. Taken together, these results suggest that PL plays an important antitumor role in processes associated with oral carcinogenesis and may be a potential phytotherapeutic target for the prevention and/or adjuvant treatment of TSCCs.

DNA methylation status of MutS genes in ameloblastoma.

OBJECTIVES: Ameloblastoma is an odontogenic epithelial tumour with a low expression of mismatch repair system components. We aimed to investigate the methylation status of the genes MSH2, MSH3 and MSH6 (MutS group) in conventional ameloblastomas. MATERIALS AND METHODS: The ameloblastoma and dental follicle samples (n = 10 each) were collected from 20 different patients. Each ameloblastoma sample was sectioned into two fragments: one was paraffin-embedded while the other one, likewise the dental follicle samples, was fixed in RNAlater and frozen at -196°C. All frozen samples were investigated for the MutS genes methylation levels, using the enzymatic restriction digestion and quantitative real-time PCR (qPCR) assay. The ameloblastoma paraffin-embedded samples were submitted to immunohistochemical reactions for MutS proteins detection and digitally quantification. Correlation analyses were performed between the immunohistochemical results and the respective gene methylation percentage. RESULTS: There are no significant differences between the MutS genes methylation levels in the ameloblastoma and the dental follicle. However, a strong negative correlation was found between MSH2 and MSH6 gene methylation status and their respective proteins expressions evaluated by immunohistochemistry. CONCLUSION: Our results show that the genes methylations is in part responsible for decreasing the expression of MSH2 and MSH6 genes in ameloblastoma.

Burkitt lymphoma of the head and neck: An international collaborative study.

BACKGROUND: Burkitt lymphoma (BL) is an aggressive B-cell lymphoma with three variants (endemic, sporadic, and immunodeficiency-associated), presenting with specific epidemiological and clinical features. Burkitt lymphoma affects the head and neck region (BLHN) in approximately 10% of cases. The aim of this study was to undertake a comparative analysis of the clinicopathologic and immunohistochemical (IHC) features of BLHN diagnosed in patients from Africa, Guatemala, and Brazil. METHODS: Cases diagnosed as BLHN were collected from the files of six oral pathology laboratory services (Brazil, South Africa, and Guatemala) and one Brazilian pediatric oncology hospital from 1986 to 2020. Clinicopathological and IHC data, and Epstein-Barr virus (EBV) status by in situ hybridization data for each case were reviewed and described. RESULTS: Of the 52 cases, BLHN was predominant in pediatric patients [43 (82.69%)] and males [43 (82.69%)], with a mean age of 11.26 ± 9.68 years (range, 1-39 years). Neck and cervical lymph nodes [14 (26.92%)], and involvement of both maxilla and mandible [8 (15.38%)], were the most common anatomical sites. Clinically, tumor/swelling [40 (31.25%)], cervical lymphadenopathy [14 (10.94%)], pain [12 (9.38%)], and bone destruction [12 (9.38%)] were frequent findings. All cases showed typical morphological characteristics of BL. IHC profiles included positivity for CD20 [52 (100%)], CD10 [38 (79.17%)], Bcl6 [29 (87.88%)], and c-Myc protein [18 (81.82%)]. EBV was positive in 18 cases (62.07%). The Ki-67 index ranged from 90 to 100%. CONCLUSION: The clinicopathological and EBV profile of BLHN in South African, Guatemalan, and Brazilian patients is similar.

Successful denosumab treatment for central giant cell granuloma in a 9-year-old child.

BACKGROUND: Denosumab is a nonsurgical treatment option for central giant cell granulomas (CGCG), especially in aggressive lesions. CASE REPORT: We describe a 9-year-old girl with an aggressive maxillary CGCG successfully treated with denosumab, avoiding a mutilating surgery after intralesional corticosteroid injections failed, and the lesion continued to rapidly grow. During denosumab treatment, she developed a self-limiting area of osteonecrosis in the maxillary alveolar bone, which rapidly resolved after antibiotic therapy. Six months after denosumab discontinuation, a maxillary surgical recontour was performed. Two weeks after surgery, the patient presented vomiting, pallor, dehydration, but no fever. Blood tests revealed severe hypercalcemia and acute renal dysfunction. After discarding thyroid, parathyroid, and adrenal alterations, a diagnosis of severe rebound hypercalcemia after denosumab treatment was made. Treatment consisted of hyperhydration, calcium pamidronate, and methylprednisolone, restoring calcium levels to normal. CONCLUSION: After 2 years of follow-up, she remains on orthodontic treatment, with no recurrences or other episodes of hypercalcemia.