Studying eruption patterns of mandibular third molars for forensic age assessment: Introducing current reference data from a population of black South Africans.

INTRODUCTION: Evaluation of the eruption of mandibular third molars in orthopantomograms (OPGs) is a method of forensic age assessment. The objective of our study was to provide valid reference data for this trait within a population of black South Africans. The study was guided by the criteria for reference studies in age assessment. MATERIALS AND METHODS: A study population from Pretoria, South Africa comprising 670 OPGs obtained from 338 black females and 332 black males aged between 15.00 and 25.97 years was analysed. All OPGs were performed for medical indication during the period from 2011 to 2022 and were retrospectively evaluated. From the 670 OPGs, a total of 1021 mandibular third molars were evaluated. The assessment of mandibular third molars was conducted using the staging scale presented by Olze et al. in 2012. Two experienced dentists evaluated the OPGs independently of each other. If the two examiners diverged in their assessments, a consensus stage was assigned. RESULTS: As expected, the mean, median and minimal age increased with higher stages for both teeth and both sexes. The minimum age recorded for stage D, indicating complete tooth eruption, was 15.79 years in females and 16.62 years in males. CONCLUSION: As it is the case for previous reference studies in other countries, placing exclusive reliance on the evaluation of mandibular third molar eruption is inadequate for ascertaining the age of majority among Black South Africans. Future studies need to examine if our results are transferable to other countries in Sub-Saharan Africa.

Clinicoradiologic features of ameloblastomas: A single-centre study of 155 cases.

BACKGROUND: The purpose of the current study was to report on the clinical presentation and radiologic features of 155 cases of ameloblastoma (AB), representing a detailed, large, single-centre radiologic study. METHODS: Histologically confirmed cases were reviewed over 11 years. Demographic and clinical data were retrieved from the patient's records. Radiologic information was analysed from available radiographs. The radiologic features of ABs were assessed according to the mean age of presentation and the mean duration of the lesion. The distinguishing radiologic features between adults/children and sex were also evaluated. RESULTS: A statistically significant correlation existed between loss of border demarcation and advanced mean age. Multilocular lesions were markedly more common in adults compared to children. Multilocular ABs were associated with increased lesion duration and advanced mean age. Radiologic signs of reactive bony changes associated with the tumour presented at the highest mean duration of all bony effects. Bony expansion and cortical destruction were statistically correlated with lesion duration. Tooth impaction was more common in children. Some mandibular lesions reached a significant size, resulting in impingement of the maxillary sinus, zygoma, orbit and pterygoid plates. CONCLUSION: Due to unfortunate healthcare access constraints, ABs grow to significant sizes and exhibit features not often reported in the literature. The findings of this analysis highlighted the radiologic features of ABs expressed through the mean age and duration of the lesion. This emphasises the significance of timely management of these lesions.

Ameloblastic carcinoma: A systematic review.

BACKGROUND: Ameloblastic carcinoma (AC) is the most common odontogenic malignancy, constituting approximately 30% of cases in this category. Literature is sparse on malignant odontogenic neoplasms, with a large proportion of current knowledge derived from case reports or small case series. METHODS: A systematic review of case series/case reports of AC was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Statement guidelines. Demographic and clinical information, including duration of the lesion, location, clinical presentation and radiologic features, were analysed. Additionally, the origin of the lesion (primary/secondary), Ki-67 proliferation index, treatment performed, metastasis, tumour recurrence and prognosis were collected for analysis. RESULTS: A total of 126 studies, including 285 individual cases of AC, were included in this review. Patients presented with a near-equal distribution of painless and painful swellings. ACs presented at a median age of 45 years, with a male-to-female ratio of 1:2. The mandible was most frequently involved, with rare cases extending to involve more than one region, including crossing the midline. Although most lesions presented with poorly-demarcated borders (52.6%), unilocular lesions with well-demarcated borders (47.4%) comprised a substantial number in the sample. The proliferation index was only reported in 27 cases, with a mean score of 42% and a wide range. The probability of tumour recurrence increased, and the survival probability decreased with prolonged follow-up duration. CONCLUSION: This study provides more comprehensive, up-to-date descriptive data on these rare odontogenic malignancies, aiding clinicians and Pathologists with the diagnosis and surgeons in their management of cases.

Targeted therapies in ameloblastomas and amelobastic carcinoma-A systematic review.

Targeted therapy has the potential to be used in the neoadjuvant setting for odontogenic tumors, reducing the morbidities associated with major surgery. In this regard, the aim of this study was to summarize the current evidence on the different forms of targeted therapy, effectiveness, and drawbacks of this course of treatment. Four databases were searched electronically without regard to publication date or language. Grey literature searches and manual searches were also undertaken. Publications with sufficient clinical data on targeted therapy for odontogenic tumors were required to meet the criteria for eligibility. The analysis of the data was descriptive. A total of 15 papers comprising 17 cases (15 ameloblastomas and 2 ameloblastic carcinomas) were included. Numerous mutations were found, with BRAF V600E being most common. Dabrafenib was the most utilized drug in targeted therapy. Except for one case, the treatment reduced the size of the lesion (16/17 cases), showing promise. Most of the adverse events recorded were mild, such as skin issues, voice changes, abnormal hair texture, dry eyes, and systemic symptoms (e.g., fatigue, joint pain, and nausea). It is possible to reach the conclusion that targeted therapy for ameloblastoma and ameloblastic carcinoma may be a useful treatment strategy, based on the findings of the included studies.

Comparative Molecular Genetics of Odontogenic Keratocysts in Sporadic and Syndromic Patients.

Odontogenic keratocysts (OKCs) are common cysts of odontogenic origin that usually occur as a single nonsyndromic cyst in isolation (sporadic) or as syndromic multiple cysts as a manifestation of naevoid basal cell carcinoma syndrome. Alterations involving the PTCH gene are the most commonly identified factor associated with up to 85% and 84% of naevoid basal cell carcinoma syndrome and sporadic cases, respectively. Other Hedgehog pathway and non-Hedgehog pathway-associated genes have been implicated in the pathogenesis of OKCs. This pilot study used the Affymetrix OncoScan molecular assay to perform a comparative genomic analysis between 4 sporadic and 3 syndromic cases of OKC to identify molecular drivers that may be common and/or distinct in these 2 groups. The majority of alterations detected in both groups were copy number neutral loss of heterozygosity. Despite distinct molecular signatures observed in both groups, copy number neutral loss of heterozygosity alterations involving chromosome 9q affecting not only PTCH but also the NOTCH1 gene were detected in all syndromic and 3 sporadic cases. Loss of heterozygosity alterations involving 16p11.2 affecting genes not previously described in OKCs were also detected in all syndromic and 3 sporadic cases. Furthermore, alterations on 22q11.23 and 10q22.1 were also detected in both groups. Of note, alterations on 1p13.3, 2q22.1, and 6p21.33 detected in sporadic cases were absent in all syndromic cases. This study demonstrates that a more common group of genes may be affected in both groups of OKCs, whereas other alterations may be useful in distinguishing sporadic from syndromic cysts. These findings should be validated in larger OKC cohorts to improve molecular diagnosis and subsequent patient management.

The "hypopigmented" bitemark: a clinical and histologic appraisal.

So-called "hypopigmented" bitemark patterns, commonly seen but not limited to dark skinned individuals, can be of value in forensic investigations. The process of aging bitemarks observed on skin is controversial and without guidelines. This report analyzes tissue obtained from the site of a hypopigmented bitemark using special histochemical stains for the identification of melanin pigment, and a panel of immunohistochemical markers to aid in the aging process. Histologic evaluation clearly showed that cellular changes in the hypopigmented area were indicative of wound healing that had taken place over a period of time. This validates the hypothesis that a hypopigmented bitemark is an indication of a wound inflicted some days previously. These findings have value in forensic investigations, particularly in cases of suspected long-term physical abuse.

Radiological aspects of lymphomas and leukaemias affecting the jaws: A systematic review.

BACKGROUND: This systematic review aimed to investigate the radiological features of lymphomas and leukaemias affecting the jaws. METHODS: A systematic literature review was conducted using the electronic databases of PubMed, Web of Science and Scopus. Articles that contained sufficient radiographic examinations (periapical, panoramic or computed tomography images) for individual cases were included. Additionally, either immunohistochemical or molecular confirmation was required prior to inclusion. Three authors evaluated and described the image quality and radiological features. RESULTS: From an initial 1079 articles screened, 129 cases were included, containing 88 tomographic, 76 panoramic and 26 periapical examinations. The quality of the majority of images was sufficient for evaluation. Diffuse large B-cell lymphoma, Burkitt lymphoma, leukemic infiltration, plasmablastic lymphoma and extranodal Natural killer (NK)/T-cell lymphoma, nasal type were the most common subtypes. Involved teeth presented with mobility in 37.2% of the cases and a provisional diagnosis of inflammatory/infectious dental disease was considered in 49.2% of cases. Computed tomography exams were available for 76% of the cases, with most presented with an osteolytic lesion with ill-defined borders. Periosteal reactions were uncommon. CONCLUSION: Lymphoma/leukaemia infiltrates of the jaw bones are usually of high-grade subtypes and rarely present with periosteal reactions.

Does BRAF V600E mutation affect recurrence rate of ameloblastomas? Systematic review and meta-analysis.

OBJECTIVE: The objective of this systematic review with meta-analysis was to critically evaluate the available data on the association of the BRAF V600E mutation and recurrence rate of ameloblastomas. MATERIALS AND METHODS: This systematic review was registered in Prospero (CRD42020183645) and performed based on the PRISMA statement. A comprehensive search in PubMed, Web of Science, Scopus and Cochrane Library databases was performed in order to answer the question "Does BRAF V600E mutation affect recurrence rate of ameloblastomas?" Methodological quality and risk of bias of the selected studies were assessed with JBI Critical Appraise Tool. Meta-analysis of quantitative data was conducted with RevMan 5.3 and Jamovi 2.3. RESULTS: The initial search identified 302 articles, and 21 met the inclusion criteria. A total of 855 subjects with ameloblastoma were included in the analysis. The pooled measures for frequency of BRAF V600E mutation was 65.30% (95% CI: 0.56-0.75; p < .001; I2 = 90.85%; τ = 0.205; p < .001), and the pooled recurrence rate was 25.30% (95% CI: 0.19-0.31; p < .001; I2 = 79.44%; τ = 0.118; p < .001). No differences in recurrence rate were observed between the BRAF V600E and wild type BRAF ameloblastomas, with a pooled Odds Ratio of 0.93 (95% CI: 0.56-1.54; p = .78; I2 = 31%; p = .09). CONCLUSIONS: BRAF V600E mutation is a frequent event in ameloblastomas, but does not increase nor reduce its recurrence rate, and thus have a limited value in predicting its prognosis.

Benign lymphoproliferative disorders in the immunosuppressed patient: an update.

Immunosuppressed patients may be affected by a wide range of lymphoproliferative disorders (LPDs) ranging from self-limiting disorders to malignant lymphoid proliferations. These LPDs may be associated with systemic immune disorders, develop following organ transplantation or occur in the background of other forms of iatrogenic immunosuppression. Lymphotropic viruses, including Epstein-Barr virus (EBV) and human herpesvirus-8 (HHV8), have been associated with the pathogenesis of distinct LPDs. The resulting classification of this group of disorders is very complex and inconsistent, with several new and emerging entities. Consequently, the diagnosis of an LPD, especially in an immunosuppressed patient, and its subsequent clinical management usually represent an important pitfall in daily clinical and pathology work. Therefore, the aim of this review was to use the available literature to describe the clinicopathological features of the most important benign LPDs that may be diagnosed in the head and neck region of immunosuppressed patients. Original clinical and microscopic images were used to illustrate some of these entities.

Oral plasmablastic lymphoma: A clinicopathological study of 113 cases.

BACKGROUND: Plasmablastic lymphoma (PBL) is an aggressive neoplasm that commonly develops in HIV-positive patients, usually affecting the oral cavity. EBV is present in the majority of cases, therefore, playing an important role in the pathogenesis of this neoplasm. METHODS: PBL diagnosed from 2000 to 2020 were retrieved from the archives of the Department of Oral Pathology and Oral Biology at the University of Pretoria, South Africa. The patients' clinical information including gender, age, tumour location and HIV status was obtained from the original histopathology request forms. A morphological description was assessed using H&E-stained slides, with diagnoses confirmed by immunohistochemistry, and EBV detection performed via in situ hybridisation. RESULTS: During the 20 years period investigated, 113 PBL were found. Males outnumbered females (M:F ratio of 3:1), with a median age of 41 years (range 8-62). The gingiva (50 cases or 44.2%) and the palate (23 cases or 20.4%) were the most affected sites. All cases with available information were HIV positive. The tumours were composed of a diffuse proliferation of immunoblasts or plasmablasts in all cases. A starry-sky pattern, tissue necrosis, cellular pleomorphism and mitotic figures were common microscopic findings. IHC for CD3 and CD20 were negative in all cases, while positivity for CD38, CD138 and MUM1 was observed in 70.2%, 79.2% and 98.9%, respectively. EBV was present in 100% of the cases. CONCLUSION: PBL is a frequent diagnosis in South Africa, due to the country's HIV burden, where it usually affects the oral cavity and is always associated with EBV infection.

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.

The relevance of taurodontism in forensic dental age estimation.

Taurodontism is a dental morphological anomaly characterized by enlarged pulp cavities repositioned towards the apical region of the tooth, coupled with shortened root structures. Molars are commonly affected by this alteration. Certain populations exhibit up to 48% prevalences for this dental alteration, underscoring its significance in dental age estimation (DAE). In the field of DAE, an individual's chronological age is inferred from specific dental features, frequently employed within the forensic context. The effect of taurodontism on the features of DAE is an unanswered issue. The influence of taurodontism on eruption, mineralization, radiographic visibility of root canals, and radiographic visibility of the periodontal ligament space in mandibular third molars- some of the established criteria for DAE as examples-is currently not systematically examined. Some common staging scales for the dental features of DAE cannot technically be applied to taurodontic teeth. Additionally, given the association of taurodontism with syndromes affecting tooth development, caution is warranted in age assessment procedures. Notably, taurodontic teeth may serve as indicators of syndromes influencing skeletal development, further emphasizing the relevance of taurodontism in forensic age assessment. Presumably taurodontic teeth were included in reference data to some extent due to their partially high prevalence in the past, whereby the influence of taurodontism has been statistically absorbed within the overall spread of the features. Future studies should compare the temporal course of these tooth characteristics in affected and unaffected teeth. Subsequent initiatives should focus on raising awareness among forensic dentists regarding taurodontism, necessitating in-depth exploration of the subject.

A radiologic-pathologic study of the histopathologic variants of ameloblastomas and their proliferation indices.

OBJECTIVES: This study aimed to analyze the clinicoradiologic features and Ki-67 proliferation indices between the histopathologic variants of ameloblastomas (ABs) for possible associations. STUDY DESIGN: The diagnosis and histopathologic variant were confirmed for all cases by experienced Oral and Maxillofacial Pathologists. Immunohistochemistry for Ki-67 was performed on the most representative formalin-fixed paraffin-embedded tissue block. Demographic, clinical data and radiologic features were analyzed from patient records and available radiographic examinations. The investigators were blinded to the histopathologic variant and proliferation index when the clinicoradiologic features were assessed. RESULTS: The current study included 116 cases of AB in the final sample. The indolent behavior of the unicystic variant was supported by their low proliferation index and slow growth paired with low frequencies of cortical destruction, loss of teeth, root resorption, and encroachment on anatomical structures. In contrast, the comparatively high proliferation index of the plexiform variant correlated with their fast growth and pain. Furthermore, high radiologic frequencies of cortical destruction, loss of teeth, and encroachment of surrounding anatomical structures supported their more aggressive clinical course. CONCLUSION: Statistically significant differences were noted between certain variants and Ki-67, location, borders, locularity, and cortical destruction, providing better insight into their biological behavior.

Histiocytic sarcoma affecting the oral cavity: a clinical, pathologic and molecular study.

OBJECTIVE: To investigate the clinicopathological, immunohistochemical and molecular features of histiocytic sarcomas affecting the oral cavity. METHODS: Pathology files of two institutions were searched for cases of histiocytic sarcoma, and new H&E-stained slides and immunohistochemistry reactions evaluated for diagnosis confirmation. Molecular screening for KRAS and PIK3CA mutations was performed through polymerase chain reaction (PCR) followed by Sanger sequencing. BRAFp.V600E mutation was assessed by pyrosequencing. Clinical data regarding sex, age, tumor location, systemic manifestations, clinical presentation, follow-up time, treatment applied and status at last follow-up were collected from patients' pathology and medical files. RESULTS: Three cases were retrieved during the period investigated (2000-2023). Two females and one male were affected, with a wide age range, involving the tongue, palate and gingiva. Histopathologically, the neoplasms presented as highly pleomorphic atypical cells distributed diffusely with infiltration of normal structures. All cases demonstrated histiocytic differentiation expressing CD68 and CD163, and a high Ki67 expression. Genetic mutations were evaluated in two cases. One case harboured BRAF-V600E mutation, but not in KRAS and PIK3CA, while the second case did not show mutation in BRAF-V600E, KRAS and PI3KCA. One patient was lost, and two patients died after eight and four months of follow-up. CONCLUSION: Histiocytic sarcomas involving the oral cavity are extremely rare, and may represent dissemination of a systemic condition. It has an aggressive biological behaviour with a poor overall prognosis.

The histology and growth rate of Nile crocodile (Crocodylus niloticus) claws.

The histology and growth of reptilian and crocodilian claws (ungues) have been extensively studied; however, Nile crocodile (Crocodylus niloticus) claws have not received adequate attention. Furthermore, age estimations for reptilian claws remain unexplored, despite Nile crocodile claws being used in long-term dietary reconstruction studies, assuming certain age-related patterns. In this study, we investigate the histology and growth patterns of Nile crocodile claws, aiming to infer axes for sampling cornified material for radiocarbon dating and establish age estimations for crocodilian claws. Our findings reveal that Nile crocodile claws exhibit growth patterns similar to other reptilians, presenting as modified scutes/scales with an age profile along the sagittal plane. This profile starts at the basal germ matrix and progressively expands in thickness and age dorsoventrally towards the apex or "tip." Consequently, the oldest corneous material is concentrated at the most dorsal point of the claw's apex. To validate previous dietary reconstruction assumptions, we conducted radiocarbon dating on this region of the claw, which supported the idea that retained corneous material in the claws is typically relatively young (5-10 years old) due to abrasion. Our study contributes insights into the histology and growth dynamics of Nile crocodile claws, shedding light on their use in dietary reconstruction studies and emphasizing the significance of considering age-related assumptions in such investigations.

Mantle cell lymphoma involving the oral and maxillofacial region: a study of 20 cases.

OBJECTIVE: To investigate the clinicopathologic features of mantle cell lymphoma (MCL) involving the oral and maxillofacial region. METHODS: The MCL cases were retrieved from the pathosis database of 6 pathology laboratories. Original hematoxylin and eosin slides and immunohistochemical reactions were reviewed for confirmation of the initial diagnosis. Clinical data of the cases were obtained from the patients' pathosis and/or medical charts. RESULTS: Twenty cases were included in the study, showing a male predominance and a mean age of 66 years. The oral cavity (12 cases) and the oropharynx (5 cases) were the most commonly involved subsites. Most cases presented as asymptomatic swellings, with 2 cases showing bilateral involvement of the palate. The classic histologic variant predominated (12/20 cases). All cases expressed CD20 with nuclear cyclin D1 positivity. SOX11 was seen in 9/13 cases, CD5 in 6/16 cases, Bcl2 in 16/19 cases, CD10 in 2/20 cases, and Bcl6 in 4/16 cases. Ki67 showed a mean proliferation index of 40.6%. The Epstein-Barr virus (EBV) was negative in all cases investigated. Follow-up data was available for 7 patients, with 5 currently alive and 2 deceased. CONCLUSION: Mantle cell lymphoma, albeit rare, may manifest in the oral and maxillofacial region. Its histologic heterogeneity demands a high degree of diagnostic skill from pathologists.

Low-Grade Myofibroblastic Sarcoma of the Oral and Maxillofacial Region: An International Clinicopathologic Study of 13 Cases and Literature Review.

Low-grade myofibroblastic sarcoma (LGMS) represents an atypical tumor composed of myofibroblasts with a variety of histological patterns and with a high tendency to local recurrence and a low probability of distant metastases. LGMS has predilection for the head and neck regions, especially the oral cavity. This study aimed to report 13 new cases of LGMS arising in the oral and maxillofacial region. This study included LGMS cases from five oral and maxillofacial pathology laboratories in four different countries (Brazil, Peru, Guatemala, and South Africa). Their clinical, radiographic, histopathological, and immunohistochemical findings were evaluated. In this current international case series, most patients were females with a mean age of 38.7 years, and commonly presenting a nodular lesion in maxilla. Microscopically, all cases showed a neoplasm formed by oval to spindle cells in a fibrous stroma with myxoid and dense areas, some atypical mitoses, and prominent nucleoli. The immunohistochemical panel showed positivity for smooth muscle actin (12 of 13 cases), HHF35 (2 of 4 cases), ß-catenin (3 of 5 cases), desmin (3 of 11 cases), and Ki-67 (range from 5 to 50%). H-caldesmon was negative for all cases. The diagnosis of LGMS was confirmed in all cases. LGMS shows predominance in young adults, with a slight predilection for the female sex, and maxillary region. LGMS should be a differential diagnosis of myofibroblastic lesions that show a proliferation of spindle cells in a fibrous stroma with myxoid and dense areas and some atypical mitoses, supporting the diagnosis with a complementary immunohistochemical study. Complete surgical excision with clear margins is the treatment of choice. However, long-term follow-up information is required before definitive conclusions can be drawn regarding the incidence of recurrence and the possibility of metastasis.

Lymphomas Affecting the Sublingual Glands: A Clinicopathological Study.

BACKGROUND: Lymphomas affecting the sublingual glands are extremely rare and very few case reports are currently available. Therefore, the aim of the current study is to describe the clinicopathological features of a series of lymphomas involving the sublingual glands. METHODS: Cases diagnosed in four pathology services were assessed and the formalin-fixed paraffin-embedded tissue blocks were retrieved for diagnosis confirmation. Clinical data were obtained from patients' medical files. RESULTS: We obtained seven cases of lymphomas in the sublingual glands, representing two follicular lymphomas, two diffuse large B cell lymphomas not otherwise specified (DLBCL NOS), two extranodal marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphomas) and one mantle cell lymphoma (MCL). In all cases the tumor cells infiltrated the glandular parenchyma, although in two of them the neoplastic cells were located more superficially and permeated the glandular acini and ducts. Clinically, the tumors presented as asymptomatic nodules and two patients (affected by DLBCL NOS and MCL) died, while the other five patients remained alive at last follow-up. CONCLUSION: Lymphomas affecting the sublingual glands are usually of the mature B cell lineage, often represent low-grade subtypes and may clinically resemble other more common lesions in the floor of the mouth like salivary gland tumors.

Acinic cell carcinoma of the oral and maxillofacial region: an international multicenter study.

The aim of this study was to describe the prevalence, clinicopathological, and prognostic features of acinic cell carcinoma (AciCC) of the oral and maxillofacial region. AciCC cases were retrospectively retrieved from 11 pathology centers of three different countries. Medical records were examined to extract demographic, clinical, pathologic, and follow-up information. A total of 75 cases were included. Females (65.33%) with a mean age of 45.51 years were mostly affected. The lesions usually presented as an asymptomatic (64.28%) nodule (95.66%) in the parotid gland (70.68%). The association of two histopathological patterns was the most common finding (48.93%) and the tumors presented mainly conventional histopathological grades (86.11%). Surgical treatment was performed in the majority of the cases (59.19%). Local recurrence was observed in 20% of the informed cases, regional metastasis in 30.43%, and distant metastasis in 12.50%. The statistical analysis showed that the cases with a solid histopathological pattern (p=0.01), high-grade transformation (p=0.008), recurrence (p=0.007), and regional metastasis (p=0.03) were associated with poor survival. In conclusion, high histopathological transformation, presence of nodal metastasis, and recurrence were prognostic factors for AciCC of the oral and maxillofacial region.

Oral follicular lymphoma: a clinicopathologic and molecular study.

Follicular lymphoma is a hematolymphoid neoplasm that originates from germinal center B cells. It is made up of a combination of small cleaved centrocytes and a varying quantity of larger non-cleaved centroblasts to describe the clinical, microscopic, immunohistochemical, and molecular features of oral follicular lymphomas. Follicular lymphomas affecting the oral cavity were retrieved from pathology files. Immunohistochemistry was performed to confirm the diagnosis, and fluorescence in situ hybridization (FISH) was employed to detect rearrangements in BCL2, BCL6, and MYC genes. Clinical and follow-up data were obtained from the patient's medical and pathology files. Twenty cases were obtained. There was an equal sex distribution (10 males: 10 females) and a mean age of 60.9 years (range: 10-83 years-old). Lesions presented as asymptomatic swellings, usually in the palate (10 cases) and the buccal mucosa (7 cases). Five patients presented with concomitant nodal involvement. Microscopic evaluation depicted the follicular growth pattern with diffuse areas in six cases. Grades 1 and 2 follicular lymphomas represented 12 cases, while grade 3A neoplasms accounted for other 8 cases. Two cases showed rearrangements in MYC, BCL2, and BCL6 genes, while single BCL2 translocation was found in eight cases. Two cases had no translocation. Three patients deceased and the 2-year overall survival achieved 88%. Follicular lymphoma affecting the oral cavity is uncommon, usually affects the palate as a non-ulcerated swelling and the presence of a systemic disease most always be ruled out.