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.

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.

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.

Clinicopathological analysis of head and neck rhabdomyosarcoma: A series of 10 cases and literature review.

BACKGROUND: To describe the clinicopathological characteristics of a series of head and neck rhabdomyosarcoma (RMS) and to review the literature. MATERIAL AND METHODS: Cases diagnosed as RMS affecting the head and neck region were retrospectively retrieved from the files of two Brazilian institutions from January 2006 to January 2017. Data on clinical features (sex, age and affected site), microscopic subtype, immunohistochemical results, treatment employed and follow-up status were obtained from the patient's medical charts. RESULTS: During the period considered, 10 cases of RMS were identified. Females predominated (4M:6F), the mean age at diagnosis was 16.5 years-old and the orbit was the most affected site (4 cases). Microscopically, most cases were classified as embryonal RMS (6 cases) and the Desmin/Myogenin/Myo-D1 immunohistochemical positivity was useful to confirm the diagnosis. Chemotherapy and radiotherapy were applied to 9 and 8 patients respectively, whereas 2 patients were treated by surgery. Recurrences occurred in 3 patients and distant metastasis in 2 cases. Nine patients were alive in their last follow-up, 3 of them with disease, whereas 1 patient died due to the disease. CONCLUSION: Head and neck RMS is an aggressive malignant neoplasm which demands especial concern to achieve early diagnosis and successful treatment.

Chikungunya fever: General and oral healthcare implications.

Chikungunya virus (CHIKV) was first isolated in humans in 1952, following an epidemic in Tanzania. The origin of the name means "to bend forward or become contorted," in reference to the posture adopted by patients due to the joint pain that occurs during the infection. Epidemiology data suggest that by the end of 2015, about 1.6 million people had been infected with CHIKV. The acute period of the disease is characterized by high fever, myalgia, joint pain, and severe and disabling polyarthritis, sometimes accompanied by headache, backache, and maculopapular rash, predominantly on the thorax. Around half of the patients will progress to the subacute and chronic phases, that is manifested by persistent polyarthritis/polyarthralgia, accompanied by morning stiffness and fatigue, which could remain for years. Oral features may include gingivitis possibly as a consequence of arthralgia of the hands leading to limited oral health measures as well as burning sensation and oral mucosal ulceration. Treatment in the acute phase includes acetaminophen, and weak opioids (tramadol or codeine) should be used in cases of severe or refractory pain. For patients who have progressed to the subacute stage and who have not had notable benefit from common analgesics or opioids, NSAIDs, or adjunctive pain medications (anticonvulsants or antidepressants) may be of benefit. In patients with moderate-to-severe musculoskeletal pain or in those who cannot be given or tolerate NSIADs or opiates, prednisolone should be prescribed.

Gingival granulomatosis with polyangiitis (Wegener's granulomatosis) as a primary manifestation of the disease.

Granulomatosis with polyangiitis (GPA) is a potentially lethal disease characterized by systemic necrotizing vasculitis, which affects small- and medium-sized blood vessels and is often associated with serum cytoplasmic antineutrophil cytoplasmic antibody. The upper and lower respiratory tract and kidney are the most involved sites, but oral lesions can be identified in 6-13% of the cases, whereas in only 2% of the cases, oral manifestations represent the first signal of the disease usually as gingival swellings or unspecific ulcerations. Without treatment, the mainstay of which is the combination of immunosuppressants and systemic corticosteroids, GPA may run a fatal course. In this report we describe an original case of GPA affecting a 75-year-old female patient referred to our service due to a gingival swelling with 3-month duration. Although the patient was correctly diagnosed and promptly treated, she died 3 months after the initial diagnosis.

Lymphoepithelial infiltrate of palatal minor salivary glands: implications for diagnostic work-up.

Benign lymphoepithelial lesions (BLLs) usually affect the parotid glands, resulting in their asymmetrical enlargement. The condition can be associated with Sjögren's syndrome (SS), which in turn may predispose the affected patient to the development of malignant lymphoma. BLLs arising in the intraoral minor salivary glands are rare; such a lesion should prompt the work-up for SS. In some instances, a BLL of a minor salivary gland could represent the initial stage of a mucosa-associated lymphoid tissue (MALT) lymphoma. A case of BLL arising in the palatal minor salivary glands is reported here. The importance of an appropriate diagnostic work-up is emphasized and the relationship of BLL with SS is reinforced.

Malignant odontogenic tumors: a multicentric Latin American study of 25 cases.

OBJECTIVE: The aim of this study was to show the epidemiological features of 25 malignant odontogenic tumors (MOT) in Latin America. MATERIALS AND METHODS: We retrieved 25 cases of MOT out of 2142 odontogenic tumors, from four oral diagnostic centers in Latin America, and described the main clinical and pathological characteristics. RESULTS: A total of 19 cases were carcinomas, including eight ameloblastic carcinomas, five primary intra-osseous squamous cell carcinomas, three clear cell odontogenic carcinomas and three ghost cell odontogenic carcinomas. All six sarcomas corresponded to ameloblastic fibrosarcoma. Thirteen cases occurred in men and 12 in women, age ranged from 7 to 77 years old, with a mean of 41.4 years. The average age of patients with carcinomas and sarcomas were 48.53 and 19 years old, respectively. CONCLUSION: As malignant odontogenic tumors are very rare, this series helps to better clarify their relative frequency, predominant subtypes, and clinical characteristics in Latin America.

Carcinoma ex pleomorphic adenoma in a Brazilian population: clinico-pathological analysis of 38 cases.

Carcinoma ex pleomorphic adenoma (CXPA) is a rare tumour, with different prevalence rates reported among studies. Epidemiological studies of large series of CXPAs in developing countries are scarce. The aim of the present study was to describe Brazilian patients with CXPA; this was a retrospective study of 38 patients. Demographic and clinico-pathological features were evaluated. No preferential gender was found, and the mean age at diagnosis was 57.6 years. The most commonly involved site was the parotid, followed by the submandibular and the minor salivary glands. A prevalence of clinical stages III and IV was observed at diagnosis. The most common histological subtypes were salivary duct carcinoma, adenocarcinoma not otherwise specified, myoepithelial carcinoma, and epithelial-myoepithelial carcinoma. Moreover, by invasive phase, most were frankly invasive carcinoma. Recurrence was observed in seven out of 24 patients with outcome information available, and all were invasive cases. All seven patients died of causes related to the disease. The distributions of cases according to age, gender, tumour location, and clinical stage were similar to those reported in the literature. Frankly invasive cases presented a worse prognosis. More information is needed to further our understanding of the clinico-pathological aspects of CXPA.

Soft tissue sarcomas of the head and neck.

This is a review of the main clinical and microscopical features of the most common sarcomas of the soft tissues of the head and neck.

Cleidocranial dysplasia: oral features and genetic analysis of 11 patients.

BACKGROUND: Cleidocranial dysplasia (CCD) is a dominantly inherited autosomal disease characterized by typical bone defects including short stature, persistently open or delayed closure of the cranial sutures, and hypoplastic or aplastic clavicles. Oral features are frequent and include supernumerary teeth, delayed eruption or impaction of the permanent teeth, and malocclusion. Heterozygous mutations in RUNX2 gene, which encodes a transcription factor essential for osteoblast differentiation, were identified as the etiological cause of CCD. OBJECTIVE AND METHODS: Herein, we performed physical and radiographic examination and screening for RUNX2 mutations in 11 patients from five families with CCD. RESULTS: All patients demonstrated the classical phenotypes related to CCD. Families whose affected members had several dental alterations such as multiple impacted and supernumerary teeth demonstrated heterozygous missense mutations (R190Q and R225Q) that impair the runt domain of RUNX2. On the other hand, CCD patients from families with low frequency of dental abnormalities showed no mutation in RUNX2 or mutation outside of the runt domain (Q292fs→X299). CONCLUSION: The current findings suggest a correlation between dental alterations and mutations in the runt domain of RUNX2 in CCD patients. Further clinical and genetic studies are needed to clarify the relationship between phenotypes and genotypes in CCD and to identify other factors that might influence the clinical features of this uncommon disease.

Expression of fatty acid synthase (FASN) in oral nevi and melanoma.

OBJECTIVE: The aim of this study was to determine the expression of fatty acid synthase (FASN) in oral nevi and melanomas, comparing the results with correspondent cutaneous lesions. MATERIALS AND METHODS: Expression of FASN was evaluated by immunohistochemistry in 51 oral melanocytic lesions, including 38 intramucosal nevi and 13 primary oral melanomas, in 10 cutaneous nevi and in 14 melanomas. RESULTS: Fatty acid synthase was strongly expressed only in melanomas, either of the oral mucosa or cutaneous. On the other hand, most oral and cutaneous nevi were negative, with a few oral cases showing focal and weak expression. CONCLUSION: Fatty acid synthase is expressed in malignant melanocytes, and it can be a helpful marker to distinguish oral melanomas from oral melanocytic nevi.

Primary xanthoma of the mandible.

Bone xanthomas are rare and are usually are associated with endocrine or metabolic diseases, mainly lipid disorders. In the absence of systemic diseases, the lesion is called a primary xanthoma. Primary mandibular xanthomas are extremely rare. The aim of this report is to describe the clinical and radiographic findings of a primary mandibular xanthoma, discussing the epidemiological features, pathogenesis and differential diagnosis. A 25-year-old man was referred for evaluation of a left mandibular lesion detected in a routine radiographic exam. Radiographically, there was a diffuse, unilocular and radiolucent lesion, with irregular margins located adjacent to the surface from the distal root of the left mandibular third molar. The lesion was excised under local anaesthesia. Microscopically, there were several cells with a foamy and granular cytoplasm and central small, round nuclei, similar to xanthomatous macrophages. No lipid disorders were diagnosed. According to these features, the diagnosis of primary mandibular xanthoma was established. In conclusion, xanthomas of the jaws are rare and all seem to be primary and occur exclusively in the mandible.

Oral squamous cell carcinoma in a 7-year-old Brazilian boy.

Squamous cell carcinomas (SCCs) are amongst the commonest malignancies in adults but in paediatric patients are exceptionally rare, particularly those involving the oral mucosa. The aim of the present report is to describe the features of a gingival well-differentiated SCC in a 7-year-old Brazilian boy. Immunostaining for p53, Ki-67 and Mcm2 showed increased cellular proliferation compared with normal epithelium. In situ hybridization failed to identify human papilloma virus infection. Correct diagnosis of well-differentiated squamous carcinoma can be difficult in children and differentiation from pseudoepitheliomatous hyperplasia is essential to establish proper treatment.

Clinicopathological factors are predictors of distant metastasis from major salivary gland carcinomas.

The risk of distant metastasis of salivary gland cancers has usually been associated with histological type, tumour size, and site. The aim of this study was to evaluate a series of patients with major salivary gland carcinomas in order to identify potential risk factors associated with distant metastasis. 255 patients treated for major salivary gland carcinoma in Brazil from 1953 to 2004 were reviewed. Clinical and treatment data were obtained from the medical records and histological features reviewed. 57 (22%) of 255 patients had distant metastasis. The lungs were the most common metastatic site (40 cases, 65%) and adenoid cystic carcinoma the most frequent histological type involved (27 cases, 47%). The percentage of tumours in the submandibular, parotid, and sublingual glands that presented distant metastasis was 42%, 20%, and 17%, respectively. These results provide evidences that clinicopathological factors (tumour site and histology) are significant predictors of distant metastasis in patients with major salivary gland carcinomas.

Clinicopathological study and treatment outcomes of 121 cases of ameloblastomas.

The aim of this paper is to evaluate the clinical, radiographic, and histopathological findings and treatment modalities in all cases of ameloblastomas treated at the Sao Paulo Cancer Hospital, between 1953 and 2003. 121 case reports were retrieved from the medical files. Data were reviewed and statistical analysis was performed using Kaplan-Meyer method and Cox proportional risk model. The patients' age ranged from 2 to 82 years (mean 33.2 years), with a slight female prevalence. Most cases were located in the posterior mandible (80%). Radiographically, 60% showed a multilocular pattern. 113 casees were solid ameloblastomas, and plexiforme subtype was the most common. Solid tumours were treated by wide resection, curettage and criosurgery, or curettage alone, and unicystic tumours by curettage and/or cryotherapy. The global mean recurrence rate was 22%, with a mean follow-up of 9.7 years. The ameloblastomas were predominantly solid, affecting the posterior mandible. Important factors for outcome were radiographically multilocular lesions, the presence of ruptured basal cortical bone and histologically follicular tumours.

Lichen sclerosus of the oral mucosa: clinicopathological features of six cases.

Lichen sclerosus is a chronic inflammatory mucocutaneous disease, rarely involving the mouth. There are only 20 well-documented cases of oral lichen sclerosus reported in the English-language literature. This report describes the clinicopathological features of 6 cases of oral lichen sclerosus; 5 in women. There were 12 lesions, mainly on the lips (50%) and buccal mucosa (25%). The affected areas appeared as irregular whitish patches, harder than the surrounding tissue. Half of the patients were symptomatic and presented with no associated skin and/or genital lesions. All cases were biopsied, and histopathological features were evaluated using hematoxylin-eosin and Verhoeff's stains, S-100 immunohistochemical reaction and transmission electron microscopy. Management of the oral lesions consisted of surgical excision, intralesional triamcinolone acetonide, oral colchicine, and regular follow-up. There is no effective curative treatment, but there are some options for patient management; and colchicine may be considered an additional choice.