Single ulcers on the tongue dorsum: differential diagnosis between paracoccidioidomycosis and squamous cell carcinoma.

BACKGROUND: Paracoccidioidomycosis (PCM) is the leading cause of death among systemic mycoses in Brazil. On the other hand, oral squamous cell carcinoma (OSCC) is the most prevalent malignant neoplasm of the mouth. Both lesions rarely affect the tongue dorsum and may share similar clinical characteristics. This study aimed to retrieve cases of single oral ulcers diagnosed as PCM or OSCC. MATERIAL AND METHODS: A cross-sectional retrospective study was conducted. All patients who had a single ulcer on dorsum of the tongue and confirmed diagnosis of PCM or OSCC were evaluated. RESULTS: A total of 9 patients (5 women and 4 men) were evaluated, 5 patients had OSCCs (mean age = 69,8 years old), and 4 patients PCM (mean age = 51 years old). Most of the lesions were infiltrated and indurated in the palpation exam. Duration ranged from 1 to 12 months (mean time of 5.2 months and 4.7 months for OSCC and PCM, respectively). OSCC was the main clinical diagnosis hypothesis. CONCLUSIONS: Although uncommon, PCM and OSCC should be considered as a diferential diagnosis hypothesis in infiltrated ulcers on the tongue dorsum. Iincisional biopsy is mandatory to confirm the diagnosis and indicate the appropriate treatment.

Lymphomas affecting the submandibular glands.

BACKGROUND: Lymphomas affecting the submandibular glands are very uncommon and few reports are currently available in the literature. Therefore, the aim of the current study is to describe the clinical and microscopic features of an original series of lymphomas affecting the submandibular glands. MATERIAL AND METHODS: The pathology files of two institutions were searched for lymphoma cases affecting the submandibular glands. The original hematoxylin and eosin, and immunohistochemical slides were revised by a pathologist for diagnosis confirmation following the revised 4th edition of the World Health Organization classification of tumours of haematopoietic and lymphoid tissues. Clinical data regarding age, sex, clinical manifestation, treatment, follow-up and status at last appointment were retrieved from the patients' medical charts. RESULTS: During the period investigated, 16 cases were included in the study. Females predominated (10:6) with a mean age of 57.8 years-old. Tumors usually presented as asymptomatic swellings. MALT lymphoma represented the most common subtype, followed by diffuse large B cell lymphoma and follicular lymphoma. Three patients died, one of them affected by plasmablastic lymphoma, one by DLBCL and one by MALT lymphoma. CONCLUSIONS: Low-grade B cell lymphomas predominate in the submandibular glands, but DLBCL and other subtypes may also be rarely diagnosed in this salivary gland.

Superficial mucoceles in cancer patients: a retrospective series from a Stomatology unit.

BACKGROUND: The aim of this study is to relate all the superficial mucoceles found in a cancer center, described the association with oncological conditions, and discuss its etiology and pathology that we found in the past few years. MATERIAL AND METHODS: Sixteen cases of superficial mucocele were retrieved from the patients' records of the Stomatology Department of the A. C. Camargo Cancer Center, São Paulo, Brazil, and demographic and clinical data were collected from electronic medical records. RESULTS: There were 16 patients, 8 patients were men and 8 women, with ages varying from 26 to 70 years old. Superficial mucoceles were observed in patients submitted to head and neck radiotherapy (n=6), graft versus host disease (n=4), one associated with oral mucositis related to allogenic bone marrow stem cells transplantation (n=1), systemic lupus (n=1), Sjögren's syndrome (n=1), oral lichenoid lesion associated with pembrolizumab (n=1) and no local or systemic inflammatory associated found (n=2). CONCLUSIONS: This study reports a series of superficial mucoceles from a single stomatology unit. Most patients had superficial mucoceles secondary to head and neck radiotherapy and graft versus host diseases. However, two patients (12.5%) had mucoceles related to systemic inflammatory conditions (Sjögren's Syndrome and Systemic Lupus).

Histomorphological evaluation, cell proliferation and endothelial immunostaining in oral and maxillofacial myofibroblastic lesions.

BACKGROUND: Myofibroblasts (MF) are mesenchymal cells with features of both fibroblasts and smooth muscle cells. Although these are usually reactive cells, they can lead to myofibroblastic tumors that may share clinical and histomorphological characteristics but with different prognosis. The aim of this study is to perform a histomorphological evaluation as well as to compare and evaluate two different cell proliferation immunomarkers and two endothelial markers in a group of oral and maxillofacial myofibroblastic lesions (MFL). MATERIAL AND METHODS: Cross-sectional and retrospective study. Demographic, clinical, histomorphological and immunohistochemical characteristics of 39 cases of MFL were analyzed. Immunohistochemical reactions were performed with the Ki67, MCM2, CD34 and CD105 antibodies. Kruskal-Wallis test and Spearman correlation analysis were used. RESULTS: Four cases of nodular fasciitis (NF), 18 myofibromas (My), 6 desmoplastic fibromas (DF), 7 inflammatory myofibroblastic tumors (IMT) and 4 myofibroblastic sarcomas (MFS) were studied. There were twenty women (51.2%); the median age was 13 [Q1-Q3: 8-24] years and most cases occurred in the mandible (48.7%). A statistically significant difference with MCM2 immunostaining (p=0.0221) was observed between the MFL; furthermore, a correlation between CD34 and CD105 immunostaining in NF (p <0.0001) and IMT (p=0.0408), between MCM2 and CD34 in IMT (p=0.0362) and between MCM2 and CD105 in MFS (p <0001) were found. CONCLUSIONS: MCM2 immunostaining could assess more clearly the cell growth fraction in MFL. The correlation between MCM2 and CD34 in IMT and between MCM2 and CD105 in MFS are indicative of the high activity of these lesions. These results emphasize the importance of the studied immunohistochemistry markers as possible tools for a better characterization of some of the MFL.

Angina bullosa haemorrhagica: A 14-year multi-institutional retrospective study from Brazil and literature review.

BACKGROUND: Angina bullosa haemorrhagica (ABH) is characterized by the recurrent appearance of blood blisters on the oral mucosa, mainly in adults' soft palate. In general, the blisters rupture spontaneously, lacking the necessity for biopsy. We report the clinical features of 23 ABH cases, emphasizing the clinical behavior and the management of these conditions. MATERIAL AND METHODS: A retrospective descriptive cross-sectional study was performed. A total of 12,727 clinical records of oral and maxillofacial lesions from four dental services in Brazil were analyzed. Clinical data were collected from the clinical records and evaluated. RESULTS: The series comprised 12 males (52.2%) and 11 females (47.8%), with a mean age of 56.8 ± 14.6 years (ranging: 24-82 years) and a 1.1:1 male-to-female ratio. Most of the lesions affected the soft palate (n = 15, 65.2%). Clinically, the lesions presented mainly as an asymptomatic (n = 17, 73.9%) blood-filled blister that ruptured after a few minutes or hours, leaving an erosion. The masticatory trauma was the most frequent triggering event. No patient had coagulation disorders. A biopsy was performed in only four cases (17.4%). Treatment was symptomatic with a favorable outcome. CONCLUSIONS: ABH is still poorly documented in the literature, and its etiology remains uncertain. ABH mainly affects the soft palate of elderly adults and has a favorable evolution in a few days. The therapeutic approach is often focused only on the relief of symptoms. However, it can share some clinical features with more serious diseases. Therefore, clinicians must recognize these lesions to avoid misdiagnosis.

HIV-related non-Hodgkin lymphomas affecting the oral cavity: a clinicopathologic study of 11 cases.

BACKGROUND: HIV-related non-Hodgkin lymphomas of the oral cavity are rare lesions with aggressive clinical behaviour. The aim of this study is to describe the clinicopathological features of a series of HIV-related oral non-Hodgkin lymphomas. MATERIAL AND METHODS: Eleven cases of oral lymphomas affecting HIV-positive patients were retrieved from 2012 to 2019. Clinicopathological features regarding age, sex, tumour location, clinical presentation, laboratory findings, disease stage and follow-up were obtained. Histologic, immunohistochemical and in situ hybridization for EBV detection were done for diagnosis confirmation. Overall survival was estimated by Kaplan-Meier curve. RESULTS: Males predominated, with a mean age of 40.3 years-old. Maxilla and mandible were the mostly affected. Plasmablastic lymphoma and diffuse large B-cell lymphoma not otherwise specified (NOS) were the main histological types. Lesions presented as reddish ulcerated swellings, representing the first sign of AIDS in six cases. Stage IV were common (7 cases) and the mean HIV viral load was 10,557 copies/mL, with a mean of 266 CD4+ cells/mm3, 1,278 CD8+ cells/mm3 and a CD4+/CD8+ ratio of 0.26. Eight patients died of the disease (72.7%). Overall survival revealed that 78.2% of the patients died after 21 months of follow-up. CONCLUSIONS: HIV-related oral lymphomas present a poor prognosis usually diagnosed in advanced stages and in our series plasmablastic lymphoma was the most common subtype.

Oral Kaposi sarcoma development is associated with HIV viral load, CD4+ count and CD4+/CD8+ ratio.

BACKGROUND: Kaposi's sarcoma (KS) is an uncommon, multifocal and angioproliferative lesion, which demonstrates a poor prognosis. The aim of the present research was to explore the association of HIV viral load, CD4+ and CD8+ counts and the CD4+/CD8+ ratio on the risk of oral Kaposi's sarcoma (KS) development. MATERIAL AND METHODS: A total of 62 patients were retrieved from March 2008 to October 2020 from the files of two oral pathology centres. Clinical, laboratory and follow-up data were retrieved from their medical files. Poisson regression was used to explore the role of history of immunosuppression and its association with oral KS development. A P-value <0.05 was considered significant. RESULTS: Sixty-two patients were included in the present study (32 with oral KS and 30 with no presentation of lesions anywhere on the body). Patients with oral KS presented a mean age of 32.6 years, and male patients were more affected. The hard palate (15 cases; 46.8%) was the main anatomical site affected. The lesions were mostly presented as swellings (13 cases; 40.6%) and nodules (12 cases; 37.5%). Systemic manifestations were also observed, including candidiasis (4 cases; 12.5%), bacterial infection (3 cases; 9.3%), tuberculosis (3 cases; 9.3%), herpes simplex (3 cases; 9.3%) and pneumonia (3 cases; 9.3%). A significant correlation was observed between HIV viral load, CD4+ count and the CD4+/CD8+ ratio with oral KS development. CONCLUSIONS: HIV viral load, CD4+ count and the CD4+/CD8+ ratio are associated with oral KS development.

Perineurioma versus meningioma. A multi-institutional immunohistochemical and ultrastructural studY.

The differential diagnosis between perineurioma (PN) and meningioma (MEN) can be difficult by histology and immunohistochemistry (IHC) because the perineurium and arachnoid have the same embryological origin. However, there are no comparative studies determining conclusive parameters for the differential diagnosis. The aim of this study is to compare IHC of PN and MEN and their ultra-structural characteristics to elucidate which are the useful data that allow differentiate both entities. Thirty-five MEN were analyzed, and 15 PN, (11 skin and soft tissues and four oral cavity). IHC for epithelial membrane antigen (EMA), Claudin-1, GLUT-1, somatostatin-2 receptor (SSTR-2), and progesterone receptor (RP) was performed. Ultrastructural studies were performed on 8 MEN and 15 PN. Only in PN Claudin-1 was positive in 9/11 (90%) cases and GLUT-1 in 7/11 (63%) cases. In MEN, the progesterone receptor was expressed in 21/35 (60%) cases and no case expressed Claudin-1 and GLUT-1; EMA was expressed in all MEN cases and 93% of PN. SSTR-2 was expressed weakly in six cases of MEN (17%), and it was not considered useful for differential diagnosis. On ultrastructure, PN showed thin and parallel processes, some caveolae, and lacked cell junctions. The cellular processes were surrounded by a collagenous stroma in 94% of the cases. MEN were characterized by curved cytoplasmic cell processes showing desmosomes in 75% of cases. Ultrastructural findings aid in the differential diagnosis between PN and MEN, especially if molecular studies are not available.

Primary melanoma of the oral cavity: A multi-institutional retrospective analysis in Brazil.

BACKGROUND: Melanoma is an aggressive malignant tumor, rarely observed in the oral cavity. The aim of this study was to describe the clinicopathologic features of a series of oral melanomas. MATERIAL AND METHODS: A retrospective descriptive study was performed. A total of 15,482 biopsy records from two oral and maxillofacial pathology services in Brazil were analyzed. All cases of oral melanomas were reviewed, and clinical, demographic, histopathological data, treatment, and follow-up status were collected. In addition, immunohistochemistry stains (pan-cytokeratin AE1/AE3, vimentin, α-SMA, CD45, S-100 protein, HMB-45, Melan A, and Ki-67) were performed. RESULTS: The series comprised of 5 males (71.4%) and 2 females (28.6%), with a mean age of 58.0 ± 9.2 years (range: 45-69 years) and a 2.5:1 male-to-female ratio. The gingiva (n = 3, 42.8%) and hard palate (n = 2, 28.6%) were the most common affected sites, presenting clinically as ulcerated swellings with a brown to black color. Cervical lymph node metastasis was detected in three patients during the first examination. Microscopically, 6 cases (85.7%) were melanotic, and one (14.3%) was amelanotic. Most cases (n = 4, 57.1%) presented a predominance of epithelioid cells. S-100 and HMB-45 were positive in all cases (n = 7, 100.0%). In contrast, only 4 cases (57.1%) were positive for Melan-A. The proliferative index with Ki-67 was high, with labeling index ranging from 70.0% to more than 90% of positive cells. Five patients died from complications of the tumors after a mean follow-up period of 7.8 months. CONCLUSIONS: Melanoma is an aggressive malignant tumor that rarely occurs in the oral cavity. It occurs mainly in adult and elderly patients and often is diagnosed in advanced stages. The current findings were similar to previous studies and reflected the characteristics of the services from where lesions were retrieved.

Malignant transformation of oral leukoplakia: a multicentric retrospective study in Brazilian population.

BACKGROUND: Among the oral potentially malignant disorders, leukoplakia stands out as the most prevalent. The purpose of this study was to analyse the clinical-pathological features of oral leukoplakia in groups of patients from three major pathology centers in two different regions of Brazil, in order to determine which factors would be associated to the clinical risk of malignant transformation. MATERIAL AND METHODS: A total of 148 patients was analyzed, and data regarding gender, age, site, classification of the clinical subtype, harmful habits such as use of tobacco and alcohol, time of evolution and presence of dysplasia were collected. The association between risk factors and malignant transformation was investigated using the chi-square test and Fischer's exact test for correlation of variables. A significance level of 5% (p≤0.05) was used. RESULTS: The mean age of the patients was 60 years, and 56% were female. Most of the lesions (34,5%) were located in the lateral and ventral regions of the tongue. Of the 148 patients, ninety had clinical follow-up. Malignant transformation occurred in 13 patients (8.8%), with an average of 44 months of follow up. CONCLUSIONS: Non-smoker, nonhomogeneous clinical presentation, location at the tongue, and the presence of high degree of dysplasia were statistically relevant factors associated with a higher risk of transformation transformation.

Comparison of the whole slide imaging and conventional light microscopy in the grading of oral epithelial dysplasia: a multi-institutional study.

BACKGROUND: Whole Slide Imaging (WSI) is an alternative method to light microscopy (LM). However, few studies have compared the diagnostic agreement between WSI and LM, especially to grade oral epithelial dysplasia (OED). The purpose of this study was to evaluate the variability in grading OED by the World Health Organization grading system, using WSI and conventional LM, and to investigate whether the access to clinical information, and psychologic or physical states of the pathologists could interfere with the diagnosis. MATERIAL AND METHODS: eleven experienced pathologists from seven Brazilian universities independently evaluated twenty-five OED cases. The analyses were performed in duplicate for each method, with an interval of at least 30 days, and the time consumed in each analysis was measured. Physical and psychologic states were evaluated by blood pressure levels, heart rate and two questionnaires: State-Trait Anxiety Inventory and Perceived Stress Scale. Clinical information was provided after the second evaluation using WSI and the pathologist could change their diagnostic decision or not. RESULTS: LM showed a higher inter-examiner agreement (k=0.53) than WSI (k=0.45) and a smaller time consumed by the pathologists (mean of 65.53 seconds compared to 91.02 seconds in WSI). In the first analysis using conventional microscopy, there was a positive correlation between kappa values and anxiety (r=0.47, p=0.02), and stress (r=0.64, p<0.01), and an inverse correlation with heart rate (r=-0.48, p=0.02). In the digital analysis, there was also a positive correlation between kappa values and anxiety (r=0.75, p<0.001). After clinical information was given, there was a slight change in 11.3% of the cases, and a great discrepancy in 1.1% of the cases, mainly increasing the OED grade. CONCLUSIONS: both microscopy systems had similar results, although LM had slightly higher kappa values, and WSI was more time consuming.

Oral pigmented lesions: a retrospective analysis from Brazil.

BACKGROUND: Pigmented lesions are uncommon in the oral mucosa, and studies investigating the incidence and types of these lesions are desired to improve the diagnostic knowledge of clinicians. The aim of this study was to analyze the distribution of oral pigmented lesions in a Brazilian population. MATERIAL AND METHODS: A retrospective descriptive cross-sectional study was performed. Oral pigmented lesions were retrieved from the files of two oral and maxillofacial pathology services from Brazil over a 45-year period (1974-2019). The clinical data and the diagnoses of each case were retrieved and included in a Microsoft Excel® database. RESULTS: From 77.074 lesions diagnosed in this period, 761 (0.99%) represented pigmented lesions of the oral mucosa, including 351 (46.1%) melanocytic and 410 (53.9%) non-melanocytic lesions, with a higher incidence in females (73.2%) between the fourth and seventh decades of life. Amalgam tattoo (53.6%) represented the most common lesion, followed by melanotic macule (18.3%) and racial pigmentation (10.8%). Other pigmented lesions included nevus (9.9%), post-inflammatory pigmentation (3%), melanoma (2.1%), melanoacanthoma (1.4%), smoker's melanosis (0.4%), drug-induced pigmentation (0.3%), and melanotic neuroectodermal tumor of infancy (0.1%). The buccal mucosa was the most commonly affected site (25.2%), followed by the alveolar ridge (14.5%), and gingiva (11.8%). CONCLUSIONS: The current findings were similar to previous studies with minor differences due methodology and characteristics of the services from where lesions were retrieved. The knowledge of these data may contribute to a better understanding of oral pigmented lesions and assist clinicians to better recognize and manage them.

Comparative expression of cyclooxygenase 2 and Ki67 in amelanotic and conventional oral melanomas.

BACKGROUND: Oral melanomas have some histopathological resemblance with its cutaneous counterpart; however, an aggressive behavior is more common in tumors that occur in the oral cavity. Several markers have been suggested as indicative of tumoral progression and aggressiveness, such as cyclooxygenase 2 (COX-2) and Ki67. MATERIAL AND METHODS: In this study, we have compared the expression of COX-2 and Ki67 in a series of amelanotic (n=7) and melanotic oral melanomas (n=22). The cases were selected from 4 pathology laboratories and submitted to the immunohistochemical (IHC) reactions. We analyzed the IHC staining based on a qualitative - using visual scores; and a computer-assisted method (quantitative) using scanned slides and software for digital analysis. RESULTS: COX-2 was expressed in all oral melanomas; however, its intensity was significantly higher in the amelanotic ones (P<0.001). Similarly, a high Ki67-positivity index was observed in the amelanotic than melanotic ones (P<0.001). CONCLUSIONS: Based on these results, we suggest that amelanotic oral melanomas have marked pro-inflammatory and high-proliferative phenotype, justifying their more aggressive behavior compared with the melanotic ones.

Epidemiologic analysis of salivary gland tumors over a 10-years period diagnosed in a northeast Brazilian population.

BACKGROUND: Salivary gland tumors (SGT) correspond to a heterogeneous group of lesions with variable biological behavior. The present study aimed to determine the distribution and demographic findings of salivary gland neoplasms in a northeast Brazilian population. MATERIAL AND METHODS: A retrospective descriptive cross-sectional study was performed. A total of 588 cases of SGT were diagnosed between 2006 and 2016 of 4 pathology services in the state of Sergipe, Brazil. All cases were reviewed, and data such as sex, age, anatomical location, and histopathological diagnosis were collected. RESULTS: A total of 470 (79.9%) tumors were benign and 118 (20.1%) were malignant. The majority of the patients were females (n=328, 55.8%) with an overall female:male ratio of 1.2:1. The major salivary glands were affected more than the minor glands (69.5% vs. 30.5%). Pleomorphic adenoma (n=419, 71.3%) and mucoepidermoid carcinoma (n=29, 4.9%) were the most frequent benign and malignant tumors, respectively. In addition, both benign and malignant tumors occurred more frequently in the parotid gland (n=300, 51%, p<0.05). CONCLUSIONS: The epidemiologic profile and clinical characteristics of SGT were similar to those described in other countries and other regions of Brazil. Epidemiological studies of SGT help to understand their clinical and pathological features and are essential to establish the proper management and prognosis.

CD1a+ and CD207+ cells are reduced in oral submucous fibrosis and oral squamous cell carcinoma.

BACKGROUND: The objective of this study investigated the distribution of immature dendritic cells (DCs), Langerhans cells and plasmacytoid DCs in oral submucous fibrosis (OSMF), OSMF associated with oral squamous cell carcinoma (OSMF-OSCC), oral leukoplakia (OL), and oral squamous cell carcinoma (OSCC). MATERIAL AND METHODS: Fourteen cases of OSMF, 9 of OSMF-OSCC, 8 of OL¸ 45 of OSCC and 8 of normal epithelium were retrospectively retrieved and their diagnoses confirmed. Immunoreactions against CD1a, CD207 e CD303 were performed and the number of positive cells quantified. RESULTS: A significant decrease of CD1a+ was found in OSMF (p≤0.05), OSMF-OSCC (p ≤ 0.01), and OSCC (p ≤ 0.001) when compared to normal epithelium. For CD207+ the significance decrease was observed in OSMF-OSCC (p ≤ 0.05), and OSCC (p ≤ 0.01) when compared with normal epithelium, and in OSMF when compared with OL (p ≤ 0.05). There was no significant difference for CD303, but increased in CD303+ was observed in OSCC when compared with normal epithelium. CONCLUSION: The decrease in the number of CD1a+ and CD207+ cells may be associate to the development of oral OSCC, and in OPMDs they might be indicators of malignant transformation.

Peri-implant peripheral giant cell lesions: report of 13 new cases and comparative histological and immunohistochemical analysis with peripheral and central giant cell lesions.

BACKGROUND: Few cases or peri-implant peripheral giant cell lesions (PGCL) have been reported in the literature. The aim of this study was to report 13 new cases of peri-implant PGCL and compare the expression of smooth muscle actin, Bcl-2 protein, GLUT-1, CD68, osteoprotegerin, receptor activator of nuclear factor kappa-B, Ki-67 and CD34 in these cases with PGCL and central giant cell lesions (CGCL). MATERIAL AND METHODS: Clinical data were retrieved from the laboratory records and histological analysis was performed using HE-stained slides. Immunohistochemical reactions for the above mentioned antibodies were performed and digitally scored. RESULTS: Peri-implant PGCL mostly affected the posterior mandible of adult females. CD68 and Bcl-2 expressions were higher in conventional PGCL and CGCL than in peri-implant PGCL ( p=0.033 for CD68 and p<0.0001 for Bcl-2). Microvessel density was higher in conventional peripheral than in central and peri-implant PGCL ( p=0.002). Proliferative index of the mononuclear cells showed no statistically significant differences comparing the three groups but it was higher in peri-implant PGCL. CONCLUSIONS: The current study demonstrated that peri-implant PGCL is more common in the posterior mandible of adult females. There were some differences in microvessel density, proliferative activity and expression of CD68 and Bcl-2 among conventional PGCL, peri-implant and CGCL. Further studies are encouraged to better understand these early findings.

Radiographic estimation of the growth rate of initially underdiagnosed ameloblastomas.

BACKGROUND: To evaluate the specific growth rate (SGR) of ameloblastoma. MATERIAL AND METHODS: cases of ameloblastoma initially underdiagnosed (e.g. cases overlooked or diagnosed as reactive lesions) which had adequate radiographic documentation to evaluate their progression were retrospectively selected. Two panoramic radiographs were analyzed to determine the specific growth rate (SGR) of each tumor, defined as the logarithm of the ratio of final tumor area (when the diagnosis of ameloblastoma was made) to the initial tumor area (when the lesion was underdiagnosed), divided by the time interval between the radiographic images. The tumor area was measured using the software ImageJ. RESULTS: Twelve patients with mandibular ameloblastomas were selected, including 5 males and 7 females, with a mean age of 24.9 years (range: 14-61 years). In four cases, the lesion was associated with the crown of an impacted third molar. In three cases, it was initially diagnosed as a periapical lesion. Three cases were extrafollicular and were not noticed in the initial radiographs. Two cases were initially diagnosed as ameloblastoma, but the surgery was delayed for personal reasons. The mean interval of time between the two radiographic images was 4.3 years (range: 0.4-9 years). Based on our analysis, ameloblastoma grows in average 40.4% per year (range: 14.9-88.7%). CONCLUSIONS: Ameloblastoma is a progressively growing tumor, but its growth rate seems to be smaller than initially reported in the literature. Better understanding the radiographic progression of ameloblastoma might improve its early diagnosis, management, and prognosis.

Intraoral lipomas: A clinicopathological study of 43 cases, including four cases of spindle cell/pleomorphic subtype.

BACKGROUND: The aim of this study was to describe the clinicopathological characteristics of 43 intraoral lipomas and classify them according to their microscopic variants. MATERIAL AND METHODS: All the cases of intraoral lipomas diagnosed at an Oral Pathology service were selected for the study. Clinical data, such as age, gender, location, time of evolution, clinical presentation, clinical hypothesis of diagnosis, and treatment, were collected from the clinical files. RESULTS: Of the 43 cases analyzed, 24 (55.8%) occurred in women. The mean age was 77.4 years. The most affected site was the buccal mucosa (22 cases, 51.1%). The mean lesion size was 1.7 cm. Twenty-three cases (53.5%) were classified as simple lipoma, 14 (32.6%) as fibrolipoma, four (9.3%) as spindle cell/pleomorphic lipoma (SC/PL), one (2.3%) as lipoma of the salivary glands, and one (2.3%) as intramuscular lipoma. In one case of SC/PLs, lipoblasts were observed. No atypical lipoblasts or mitoses were noted. Lipoma was considered more often than other tumor histological subtypes among the clinical hypotheses of diagnosis when the final diagnosis was simple lipoma (p=0.01). CONCLUSIONS: Intraoral lipomas present different clinical presentation depending on the histological subtype. In SC/PLs, lipoblasts with vacuolated cytoplasm may be found and the presence of mature adipocytes is essential for diagnosis.

Benign epithelial oral lesions - association with human papillomavirus.

BACKGROUND: The presence of human papilloma virus in benign oral lesions has been studied by different techniques obtaining extremely variable results. The objective of this study was to determine the presence of human papillomavirus in 83 cases of benign hyperplastic epithelial oral lesions. MATERIAL AND METHODS: Eighty-three oral lesions with clinical or histopathological features suggestive of HPV infection were retrieved from the files of four oral pathology services. Demographic data were obtained from patient's medical charts. All cases had available clinical image, H&E preparations and paraffin blocks with enough tissue for HPV detection by in situ hybridization, and immunohistochemical reactions for Ki67. RESULTS: Episomal positivity for wide spectrum HPV was observed in 24% of the cases; most of them (70%) HPV 6/11 positive. HPV 16/18 was not detected. Condyloma acuminatum was the most common lesion associated with HPV (75%), followed by verruca vulgaris (15%), squamous papilloma and multifocal epithelial hyperplasia, 5% each. Koilocytes were identified in all the HPV positive cases. Ki67 showed an abnormal proliferation pattern in 90% of the HPV positive cases; most of them (70%) showing groups of proliferating cells in focal superficial regions, and in 20% positivity was seen almost in the whole thickness of the epithelium. HPV negative cases showed Ki67 positive cells restricted to the basal layer. CONCLUSIONS: Regarding oral lesions associated with HPV, condyloma is the most common lesion expressing low-risk subtypes. The etiology of squamous papilloma remains controversial as HPV was found in 1.9% of the cases. The identification of koilocytes and the pattern of expression of Ki67 reflect HPV infection and are helpful for classification. Papillary oral lesions not associated to HPV deserve further studies to better clarify its etiology.