Primordial Odontogenic Tumor: A Review of the Literature and Report of Three New Patients.

The primordial odontogenic tumor (POT) is a rare mixed odontogenic tumor composed of mesenchymal cells, columnar odontogenic epithelium, and fibromyxoid stroma affecting the posterior mandible of children and adolescents. Herein, we report 3 patients with POT and the clinicopathological features of POT previously reported in the literature. A 12-year-old, 19-year-old, and 4-year-old patient presented an asymptomatic swelling in the posterior maxilla and posterior mandible. Imaging exams revealed radiolucent lesions associated with unerupted teeth. The lesions were surgically removed, and the histopathological examination revealed spindle-to-ovoid mesenchymal cells in a fibromyxoid stroma surfaced by columnar odontogenic epithelial cells with reverse nuclear polarization. Deposition of mineralized tissue was observed. The final diagnosis was POT, and patients did not exhibit signs of recurrence. POT should be included in the differential diagnoses of intraosseous lesions in the posterior mandible in pediatric patients.

Clinicopathologic and imaging features of odontogenic myxomas: a multi-institutional study.

PURPOSE: This study aims to report clinicopathologic and imaging features of odontogenic myxomas (OM), highlighting uncommon findings. METHODS: Clinicopathologic and imaging data of OMs diagnosed in the five Brazilian diagnostic pathology centers were collected and analyzed. RESULTS: The series comprised 42 females (68.9%) and 19 males (31.1%), with a 2.2:1 female-to-male ratio and a mean age of 34.5±15.4 years (range: 4-80). Clinically, most OMs presented as painless intraoral swelling (n = 36; 70.6%) in the mandible (n=37; 59.7%). Multilocular lesions (n=30; 83.3%) were more common than unilocular lesions (n=6; 16.7%). There was no statistically significant difference between the average size of unilocular and multilocular OMs (p=0.2431). The borders of OMs were mainly well-defined (n=24; 66.7%) with different degrees of cortication. Only seven tumors caused tooth resorption (15.9%), while 24 (54.5%) caused tooth displacement. Cortical bone perforation was observed in 12 (38.7%) cases. Morphologically, OMs were characterized mainly by stellate or spindle-shaped cells in a myxoid background (n=53; 85.5%). Surgical resection was the most common treatment modality (n=15; 65.2%), followed by conservative surgery (n=8; 34.8%). Outcomes were available in 20 cases (32.3%). Seven of these patients had local recurrence (35%). Enucleation was the treatment with the highest recurrence rate (4/7; 57.1%). CONCLUSIONS: OM has a predilection for the posterior region of the jaws of female adults. Despite their bland morphological appearance, they displayed diverse imaging features. Clinicians must include the OM in the differential diagnosis of osteolytic lesions of the jaws. A long follow-up is needed to monitor possible recurrences.

Oral granular cell tumor: a collaborative clinicopathological study of 61 cases.

BACKGROUND: Granular Cell Tumor (GCT) is an uncommon benign lesion in the oral cavity whose pathogenesis remains poorly understood. Due to their infrequent occurrence and similarity to other oral lesions, they are often forgotten during the initial clinical diagnosis. Therefore, understanding its prevalence, clinical and pathological characteristics is crucial for an accurate diagnosis and adequate management. METHODS: All cases diagnosed as GCTs in six Brazilian and Argentinian oral diagnostic centers were re-evaluated by HE staining, and clinical, demographic, and histopathological data were collected and evaluated. RESULTS: The series comprised 45 female (73.8%) and 16 male (26.2%), with a 2.8:1 female-to-male ratio and a mean age of 35.3 ± 16.9 years (range: 7-77 years). Most cases occurred on the tongue (n = 49; 81.6%) and presented clinically as asymptomatic papules or nodules (n = 50; 89.3%) with a normochromic (n = 25; 45.5%) or yellowish (n = 11; 20.0%) coloration and sizes ranging from 0.2 to 3.0 cm (mean ± SD: 1.40 ± 0.75 cm). Morphologically, most tumors were characterized by a poorly delimited proliferation (n = 52; 88.1%) of cells typically rounded to polygonal containing abundant, eosinophilic, finely granular cytoplasm. Pustulo-ovoid bodies of Milian were identified in all lesions (n = 61; 100%). Entrapment of skeletal striated muscle (n = 44; 72.1%) and nerve fibers (n = 42; 68.9%) were common findings. Pseudoepitheliomatous hyperplasia (PEH) was observed in 23 cases (39.0%). In only 27.7% of cases (n = 13) there was agreement between the clinical and histopathological diagnosis. Outcome information was available from 16 patients (26.2%), with clinical follow-up ranging from 4 to 36 months (mean 13.3 months), and none developed local recurrence. CONCLUSIONS: The clinical and histopathological features of GCTs were consistent with those described in previous studies. In general, these lesions have a predilection for the lateral region of the tongue in adult women. It is essential to consider GCTs in the differential diagnosis of yellow or normochromic papules and nodules in the oral cavity. Histopathological evaluation is essential for the definitive diagnosis and the prognosis is excellent.

BubR1 and cyclin B1 immunoexpression in pleomorphic adenoma and polymorphous adenocarcinoma of minor salivary glands.

The immunoexpression of BubR1 and cyclin B1 in pleomorphic adenoma (PA) and polymorphic adenocarcinoma (PAC) in minor salivary glands is poorly studied. Thus, a retrospective and observational study was performed to provide a better understanding of the role and immunopositivity patterns of these proteins in these lesions. Sixteen cases of PA and 16 cases of PAC were selected. Parenchyma cells were submitted to quantitative immunohistochemical analysis through the labeling index. Cytoplasmic immunoexpression of BubR1 was observed in neoplastic cells from all analyzed PA and PAC cases. All PA cases and 93.7% of PAC exhibited nuclear immunoexpression of BubR1. Higher cytoplasmic and nuclear immunoexpression of BubR1 was observed in PAC (p = 0.001 and p = 0.122, respectively). Cytoplasmic immunoexpression of cyclin B1 was observed in all cases of PA and PAC, with a higher labeling index in the latter (p < 0.001). There was a significant positive correlation between nuclear and cytoplasmic BubR1 immunoexpressions (p < 0.001) in PA and a significant negative correlation between BubR1 and cyclin B1 cytoplasmic immunoexpressions (p = 0.014) in PAC. The higher cytoplasmic and nuclear immunoexpression of BubR1 in PACs suggests the continuous maintenance of neoplastic cells in the cell cycle and migration. Higher immunoexpression of cyclin B1 supports this lesion's enhanced proliferative and migration ability.

A retrospective multicenter study of oral and maxillofacial lesions in older people.

Few studies on the distribution of oral diseases in older people are available in the literature. This study aimed to investigate the prevalence and demographic characteristics of oral and maxillofacial lesions in geriatric patients (age ≥ 60 years). A retrospective descriptive cross-sectional study was performed. Biopsy records were obtained from archives of three Brazilian oral pathology centers over a 20-year period. Data on sex, age, anatomical site, skin color, and histopathological diagnosis were collected and analyzed. Pearson's chi-square test was used to evaluate differences in the frequency of the different oral and maxillofacial lesion groups. A total of 7,476 biopsy records of older patients were analyzed. Most cases were diagnosed in patients aged 60 to 69 years (n = 4,487; 60.0%). Females were more affected (n = 4,403; 58.9%) with a female-to-male ratio of 1:0.7 (p < 0.001). The tongue (n = 1,196; 16.4%), lower lip (n = 1,005; 13.8%), and buccal mucosa (n = 997; 13.7%) were the most common anatomical sites. Reactive and inflammatory lesions (n = 3,840; 51.3%) were the most prevalent non-neoplastic pathologies (p < 0.001), followed by cysts (n = 475; 6.4%). Malignant neoplasms were more frequent (n = 1,353; 18.1%) than benign neoplasms (n = 512; 6.8%). Fibrous/fibroepithelial hyperplasia (n = 2,042; 53.2%) (p < 0.001) and squamous cell carcinoma (n = 1,191; 88.03%) (p < 0.001) were the most common oral lesions in older adults. Biopsy data allow the accurate characterization of the prevalence of oral and maxillofacial lesions, supporting the development of public health policies that can enable the prevention, early diagnosis, and appropriate treatment of these lesions. Also, they bring valuable information that helps dentists and geriatricians diagnose these diseases.

Oral solitary fibrous tumors: A collaborative clinicopathologic study of 19 cases.

OBJECTIVE: To report the clinicopathologic features of 19 oral solitary fibrous tumors (SFTs). METHODS: Clinical data were collected from the records of seven pathology services. All cases were re-evaluated by HE staining and confirmed by immunohistochemistry. RESULTS: The series comprised 11 females (57.9%) and 8 males (42.1%), with a mean age of 47.3 ± 14.7 years (range: 22-71 years) and a 1.3:1 female-to-male ratio. Most tumors affected the buccal mucosa (n = 7; 36.8%) and presented clinically as an asymptomatic solitary submucosal well-circumscribed nodule with coloration similar to the oral mucosa. Morphologically, most SFTs (n = 10; 52.6%) exhibited a classic hybrid pattern characterized by a well-circumscribed proliferation of densely cellular areas alternating with hypocellular areas in a variably collagenous vascular stroma. Remnants of accessory salivary glands were observed in two cases (n = 2; 10.5%). All tumors were positive for STAT6 and CD34 (n = 19; 100%). Outcome information was available from 6 patients (31.6%), with clinical follow-up ranging from 6 to 24 months (mean ± SD, 9.5 ± 6.8 months), and none developed local recurrence. CONCLUSIONS: Oral SFTs are rare and often clinically misdiagnosed. Pathologists should consider SFT in the differential diagnosis of oral spindle cell tumors. Accurate diagnosis requires careful morphological evaluation supported by immunohistochemical analysis.

Immunoexpression of Autophagy-Related Proteins in Salivary Gland Tumors: An Exploratory Study.

BACKGROUND: Autophagy is a cellular survival mechanism involved in several human diseases, but its participation in the development of salivary gland tumors is not fully understood. This study investigated the immunoexpression of autophagy-related proteins (autophagy-related 7 [Atg7], microtubule-associated protein 1 light chain 3A [LC3A], microtubule-associated protein 1 light chain 3B [LC3B], protein p62 [p62], and phosphorylated mammalian target of rapamycin [p-mTOR]) in pleomorphic adenoma (PA), polymorphous adenocarcinoma (PAC), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (ACC) of salivary glands. METHODS: Twenty PAs, 20 PACs, 20 MECs, and 14 ACCs were selected. The percentages of cytoplasmic and nuclear positivity for autophagy-related proteins in neoplastic cells were assessed and correlated with histopathological parameters. RESULTS: Cytoplasmic immunoexpression of Atg7 was observed in all groups, with high median percentages of positivity. Regarding LC3A and LC3B, cytoplasmic immunoexpression was found in most PACs (95%) and in all cases of PA, MEC and ACC, with the highest percentages of positivity in PACs and PAs (p < 0.005). ACCs exhibited lower cytoplasmic immunoexpression of p-mTOR (p < 0.005) and lower nuclear expression of p62 (p < 0.05) when compared to PAs, PACs and MECs. Low nuclear immunoexpression of Atg7, LC3A and p-mTOR and absence of nuclear staining for LC3B were observed in all groups. Regarding histopathological parameters of PAs, MECs and ACCs, there were no significant differences in the expression of autophagy-related proteins. In all groups, positive correlations were observed between the immunoexpression of some autophagy-related proteins (p < 0.05). CONCLUSIONS: The results suggest the participation of autophagy in the pathogenesis of PA, PAC, MEC, and ACC of salivary glands. Upregulation of autophagy and reduced nuclear translocation of p62 may contribute to the aggressive biological behavior of salivary gland ACC.

Gingival rhabdomyosarcoma mimicking a non-neoplastic proliferative lesion: A diagnostic challenge.

Rhabdomyosarcoma (RMS) is a soft tissue sarcoma that develops from skeletal striated muscle cells. RMSs are exceedingly rare in the oral cavity, particularly in the gingiva. Herein, we reported the clinicopathological and immunohistochemical features of a rare case of RMS in a 30-year-old female presenting clinically as a painful polypoid nodule on the mandibular gingiva. Microscopically, the tumor showed atypical spindle cells with elongated nuclei and eosinophilic cytoplasm arranged in a fascicular pattern. In focal areas, the tumor cells exhibited rhabdomyoblastic differentiation. Immunohistochemistry showed strong positivity for desmin, myogenin (scattered cells), and MyoD1. The patient underwent surgical resection followed by postoperative complementary radio- and chemotherapy. However, the patient had a local recurrence seven months after the initial treatment. She was submitted to a total mandibulectomy associated with adjuvant radiotherapy. However, she died two months after reoperation due to complications secondary to radiation therapy. Because of the rarity in the oral cavity and non-specific signs and symptoms, the clinical diagnosis of RMS is difficult and often overlooked. Therefore, careful histopathological and immunohistochemistry analysis of these tumors is essential to correct diagnosis. Early surgical excision with tumor-free margins and prolonged follow-up are strongly recommended.

A retrospective multicenter study of oral and maxillofacial lesions in older people

Abstract Few studies on the distribution of oral diseases in older people are available in the literature. This study aimed to investigate the prevalence and demographic characteristics of oral and maxillofacial lesions in geriatric patients (age ≥ 60 years). A retrospective descriptive cross-sectional study was performed. Biopsy records were obtained from archives of three Brazilian oral pathology centers over a 20-year period. Data on sex, age, anatomical site, skin color, and histopathological diagnosis were collected and analyzed. Pearson's chi-square test was used to evaluate differences in the frequency of the different oral and maxillofacial lesion groups. A total of 7,476 biopsy records of older patients were analyzed. Most cases were diagnosed in patients aged 60 to 69 years (n = 4,487; 60.0%). Females were more affected (n = 4,403; 58.9%) with a female-to-male ratio of 1:0.7 (p < 0.001). The tongue (n = 1,196; 16.4%), lower lip (n = 1,005; 13.8%), and buccal mucosa (n = 997; 13.7%) were the most common anatomical sites. Reactive and inflammatory lesions (n = 3,840; 51.3%) were the most prevalent non-neoplastic pathologies (p < 0.001), followed by cysts (n = 475; 6.4%). Malignant neoplasms were more frequent (n = 1,353; 18.1%) than benign neoplasms (n = 512; 6.8%). Fibrous/fibroepithelial hyperplasia (n = 2,042; 53.2%) (p < 0.001) and squamous cell carcinoma (n = 1,191; 88.03%) (p < 0.001) were the most common oral lesions in older adults. Biopsy data allow the accurate characterization of the prevalence of oral and maxillofacial lesions, supporting the development of public health policies that can enable the prevention, early diagnosis, and appropriate treatment of these lesions. Also, they bring valuable information that helps dentists and geriatricians diagnose these diseases.

Oral mucoceles: A Brazillian Multicenter Study of 1,901 Cases.

Oral mucocele (OM) is the most common lesion of minor salivary glands. The present study aimed to report the clinical and demographic features of a large series of OMs and identify possible predictive variables associated with the recurrence rate of these lesions. A retrospective descriptive cross-sectional study was performed. A total of 43,754 biopsy records from four pathology services in Brazil were analyzed. All cases of OMs were reviewed, and clinical and demographic data were collected. The study comprised 1,002 females (56.2%) and 782 males (43.8%), with a mean age of 19.8±16.4 years (range: 01-87 years) and a 1.3:1 female-to-male ratio. The lower lip (n=1,160; 67.4%), and floor of the mouth (n=172; 10.0%), were the most common affected sites, presenting clinically as nodules (n=978; 79.4%) of smooth surface (n=428; 77.5%) and normal color (n=768, 46.7%). Excisional biopsy was the treatment in most cases (n=1,392; 78.0%). Recurrent OMs represented 6.2% of all diagnosed cases (n=117). OMs recurred more commonly in younger patients (aged<20 years) (p<0.0001), in lesions larger than 2 cm in diameter (p<0.0001), and in those located in the ventral tongue (p=0.0351). Also, recurrence rates were higher significantly in cases treated with laser surgery than in those with conventional surgery (p=0.0005). Patients with OMs should be carefully informed of its possible recurrence, especially when found on the ventral tongue of young patients.

Oral mucoceles: A Brazillian Multicenter Study of 1,901 Cases

Abstract Oral mucocele (OM) is the most common lesion of minor salivary glands. The present study aimed to report the clinical and demographic features of a large series of OMs and identify possible predictive variables associated with the recurrence rate of these lesions. A retrospective descriptive cross-sectional study was performed. A total of 43,754 biopsy records from four pathology services in Brazil were analyzed. All cases of OMs were reviewed, and clinical and demographic data were collected. The study comprised 1,002 females (56.2%) and 782 males (43.8%), with a mean age of 19.8±16.4 years (range: 01-87 years) and a 1.3:1 female-to-male ratio. The lower lip (n=1,160; 67.4%), and floor of the mouth (n=172; 10.0%), were the most common affected sites, presenting clinically as nodules (n=978; 79.4%) of smooth surface (n=428; 77.5%) and normal color (n=768, 46.7%). Excisional biopsy was the treatment in most cases (n=1,392; 78.0%). Recurrent OMs represented 6.2% of all diagnosed cases (n=117). OMs recurred more commonly in younger patients (aged<20 years) (p<0.0001), in lesions larger than 2 cm in diameter (p<0.0001), and in those located in the ventral tongue (p=0.0351). Also, recurrence rates were higher significantly in cases treated with laser surgery than in those with conventional surgery (p=0.0005). Patients with OMs should be carefully informed of its possible recurrence, especially when found on the ventral tongue of young patients.

Resumo A mucocele oral (MO) é a lesão mais comum das glândulas salivares menores. O presente estudo teve como objetivo relatar as características clínicas e demográficas de uma grande série de MOs e identificar possíveis variáveis preditivas associadas à taxa de recorrência dessas lesões. Foi realizado um estudo transversal descritivo retrospectivo. Foram analisados 43.754 registros de biópsias de quatro serviços de patologia no Brasil. Todos os casos diagnosticados como MOs foram revisados e dados clínicos e demográficos foram coletados. Participaram do estudo 1.002 mulheres (56,2%) e 782 homens (43,8%), com média de idade de 19,8 ± 16,4 anos (variação: 01-87 anos) e proporção de mulheres para homens de 1,3:1. O lábio inferior (n=1.160; 67,4%) e assoalho da boca (n=172; 10,0%), foram os locais mais acometidos, apresentando-se clinicamente como nódulos (n=978; 79,4%) de superfície lisa (n =428; 77,5%) e coloração normal (n=768, 46,7%). A biópsia excisional foi o tratamento na maioria dos casos (n=1.392; 78,0%). As MOs recorrentes representaram 6,2% de todos os casos diagnosticados (n = 117). As recorrências recorreram mais comumente em pacientes mais jovens (idade < 20 anos) (p < 0,0001), em lesões maiores que 2 cm de diâmetro (p < 0,0001) e naquelas localizadas na superfície ventral da língua (p = 0,0351). Além disso, as taxas de recorrência foram significativamente maiores nos casos tratados com cirurgia a laser do que aqueles com cirurgia convencional utilizando bisturi (p = 0,0005). Pacientes com mucoceles devem ser informados sobre uma possível recorrência, principalmente quando encontrados no lábio ou assoalho bucal de pacientes jovens.

Intraosseous rhabdomyosarcoma of the maxilla with TFCP2 fusion: A rare aggressive subtype with predilection for the gnathic bones.

Rhabdomyosarcomas (RMS) are malignant tumors with skeletal muscle differentiation extremely rare in intraosseous sites. We reported a rare case of an aggressive intraosseous RMS found in the maxilla of a 17-year-old female patient with five months of evolution. Computed tomography revealed a large osteolytic lesion extending from tooth 21 to 27, causing buccal and lingual cortical plate perforation. Microscopically, the lesion showed a proliferation of spindle-shaped cells with elongated nuclei and eosinophilic cytoplasm, arranged in an interlaced fascicle pattern. The nuclei ranged from vesicular with distinct nucleoli to hyperchromatic. A focal component of plump to epithelioid cells with a moderate amount of eosinophilic cytoplasm was seen at the periphery of the tumor. The immunohistochemical analysis revealed positivity for desmin, MyoD1, and myogenin (scattered cells). S-100, SOX10, HMB45, ß-catenin, and CD34 were negative. Ki-67 was positive in 30% of tumor cells. Fluorescence in situ hybridization (FISH) analysis showed the presence of a FUS-TFCP2 fusion. The diagnosis was intraosseous RMS with TFCP2 fusion. Surgical excision followed by chemo- and radiotherapy was carried out; however, the patient died of disease nine months after the treatment. Because of the rarity and non-specific signs and symptoms, the clinical diagnosis of intraosseous RMS is difficult and often overlooked. Therefore, careful histopathological evaluation, supported by immunohistochemical and molecular analysis, is essential to correct diagnosis. Early surgical excision with tumor-free margins and prolonged follow-up are strongly recommended.

Immunoexpression of CXCL12 and CXCR4 in sporadic and Gorlin-Goltz syndrome-related odontogenic keratocysts.

Background: Differences in the pathogenesis and biological behavior of sporadic and Gorlin-Goltz syndrome-related odontogenic keratocysts (OKCs) have been reported, but the underlying mechanisms are not fully elucidated. Chemokine CXCL12 and its main receptor CXCR4 regulate important events in the pathogenesis of several lesions. Material and Methods: This study evaluated the immunoexpression of CXCL12 and CXCR4 in sporadic and syndromic OKCs. Twenty-two sporadic OKCs and 22 syndromic OKCs were subjected to immunohistochemistry. The percentages of cytoplasmic (CXCL12 and CXCR4) and nuclear (CXCR4) staining in epithelial and fibrous capsule cells were determined. The results were analyzed statistically using the nonparametric Mann-Whitney test and Spearman correlation test (p<0.05). Results: Higher cytoplasmic expression of CXCL12 was observed in the epithelial lining and fibrous capsule of sporadic OKCs compared to syndromic OKCs (p<0.001). No statistically significant differences in the cytoplasmic expression of CXCR4 were observed between syndromic OKCs and sporadic OKCs (p>0.05). Compared to syndromic OKCs, sporadic OKCs exhibited higher nuclear expression of CXCR4 in the epithelial lining and lower immunoexpression in the fibrous capsule (p<0.05). In the epithelial lining of syndromic OKCs, positive correlation was observed between cytoplasmic and nuclear expressions of CXCR4 (p=0.003). In the fibrous capsule of syndromic OKCs and sporadic OKCs, cytoplasmic and nuclear expressions of CXCR4 were positively correlated (p<0.001). Conclusions: The results suggest a potential participation of CXCL12 and CXCR4 in the development of OKCs. The heterogeneous expression of these proteins in syndromic and sporadic OKCs may reflect differences in their pathogenesis and biological behavior. Key words:Odontogenic keratocyst, CXCL12, CXCR4, Immunohistochemistry.

Oral Lymphoepithelial Cyst: A Collaborative Clinicopathologic Study of 132 Cases from Brazil.

The oral lymphoepithelial cyst (OLC) is an uncommon lesion whose pathogenesis remains poorly understood. The aim of this study was to report the clinicopathologic features of the OLCs and to verify a possible association between OLCs and subgemmal neurogenous plaque (SNP) in the posterior lateral region of the tongue. A retrospective descriptive cross-sectional study was carried out. A total of 106,282 biopsy records of oral and maxillofacial lesions from six oral pathology services in Brazil were analyzed. All cases of OLCs were reviewed, and clinical and histopathological data were collected. Immunohistochemical reactions for S-100 protein were performed to confirm the diagnosis of SNP. Among all lesions, there were 132 (0.11%) cases of OLCs. The series comprised 83 females (62.9%) and 49 males (37.1%), with a 1.7:1 female-to-male ratio and a mean age of 45.8 ± 17.7 years. Most cases involved the tongue (n = 80; 62.0%) and presented clinically as asymptomatic papules or nodules with a yellow or whitish color. Microscopically, most of the cysts were entirely lined by parakeratinized stratified epithelium (n = 89; 67.4%) and filled with desquamated cells, keratin debris, amorphous eosinophilic material, and inflammatory cells in varying amounts. Connection with the epithelium of oral mucosa was observed in 18 cases (13.6%). SNP was found in 9/80 (11.2%) cases involving the tongue. The clinical and demographic features of OLCs were similar to those described in previous studies. Overall, this lesion has a predilection for the posterior region of the tongue of female adults. Clinicians must include the OLC in the differential diagnosis of yellow/white papules and nodules of the oral cavity.

Evaluation of HPV and EBV in OSCC and the expression of p53, p16, E-cadherin, COX-2, MYC, and MLH1.

OBJECTIVE: This study aimed to evaluate the presence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) and the expression of p53, p16, E-cadherin, COX-2, MLH1, and MYC in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: One hundred OSCC specimens were submitted to in situ hybridization for HPV and EBV, and immunohistochemistry for detection of the human proteins. RESULTS: Thirty-one cases showed HPV in tumor tissue. EBV was not detected in any case investigated. The HPV(+) group demonstrated an increase of staining scores for nuclear p16 (p = .047), cytoplasmic MYC (p = .002), while a decrease for nuclear MLH1 (p = .048), suggesting that HPV may upregulate the expression of the first two proteins and down-regulate the latter. CONCLUSION: Our findings reinforce the hypothesis of the HPV-related oral carcinogenesis involving the expression of p16 and MYC, and MLH1 suppression. Exclusively cytoplasmic stainings for p16, MLH1, and MYC were also associated with more advanced tumors. Finally, in view of the lack of studies correlating the HPV or EBV infection to the expression of oncoproteins, more researches assessing a broader panel of markers and employing different approaches are still necessary in order to understand the role of these viruses as well as the molecular mechanisms involved in the development and progression of oral carcinomas.

Fixation of free gingival grafts with cyanoacrylate glues: A histomorphometric and immunohistochemical study.

AIM: The objective of this study was to evaluate the inflammatory process resulting from the use of two cyanoacrylate-based adhesives to stabilize grafts. METHODOLOGY: A total of 45 male Wistar rats were randomly divided into three groups (n = 15/group) treated with ethyl cyanoacrylate glue (TG1), octyl-2-cyanoacrylate glue (TG2) or suture threads (CG). After de-epithelialization in the anterior gingival region of the mandible, the graft was removed from the donor site (hard palate), taken to the recipient site and stabilized according to the protocol of each group. After 7, 14, and 45 days, the animals were euthanized. The graft area was analysed macroscopically, histologically, histochemically (Masson trichrome), and immunohistochemically positive cell count for TGF-ß, α-SMA, RANKL, OPG, FGF, and IL-10. The Kruskal-Wallis/Dunn test (SPSS 20.0, p < 0.05) was used for analysis. RESULTS: There was no difference in the clinical parameters among the three groups, but TG1 showed the lowest mononuclear inflammatory cell count and the highest amount of total collagen. FGF immunoexpression was significantly higher for the CG group, but the TG2 showed a significant reduction in the RANKL/OPG ratio. CONCLUSION: TG1 had a mild inflammatory response and a higher collagen deposition than other glues, and TG2 had a reduction in the RANKL / OPG ratio.

Sialolipomas of minor salivary glands: A multi-institutional study and literature review.

BACKGROUND: Sialolipoma is a rare histological variant of lipoma commonly misdiagnosed and composed of a proliferation of mature adipocytes with secondary entrapment of normal salivary gland tissue. The purpose of the present study is to report the clinicopathologic and immunohistochemical features of 10 new cases of sialolipomas in conjunction with a review of the literature. METHODS: A retrospective descriptive cross-sectional study was performed. A total of 54,190 biopsy records of oral and maxillofacial lesions from four oral and maxillofacial pathology services in Brazil were analysed. All cases of lipomas were reviewed, and clinical, demographic and histopathological data were collected of all cases compatible with sialolipomas. In addition, immunohistochemistry stains (AE1/AE3, CK7, 34ßE12, S-100, HHF35, α-SMA and Ki-67) and a literature review based on a search of three electronic databases (PubMed, Web of Science and Scopus) were performed. RESULTS: Among all lipomas reviewed, there were 10 cases of sialolipomas. The series comprised of 7 females (70.0%) and 3 males (30.0%), with a mean age of 46.1 ± 21.5 years (range: 11-71 years) and a 2.3:1 female-to-male ratio. The lower lip (n = 3, 30.0%) and tongue (n = 2, 20.0%) were the most common locations, presenting clinically as a nodule of slow growth and normal colour. Conservative surgical excision was the treatment in all cases. No recurrence was observed. CONCLUSION: Sialolipomas are a rare histological variant of lipoma, affecting the salivary glands, mainly in the parotid gland and palate of female adults. Pathologists must recognise sialolipomas to avoid misdiagnoses with other lipomatous tumours that can affect salivary glands.

CD133 Role in Oral Carcinogenesis.

OBJECTIVE: to investigate CD133 immunoexpression, cancer stem cells marker, in oral epithelial dysplasias (OEDs) and oral squamous cells carcinomas (OSCCs) and understandits possible involvement in the malignant transformation process of these lesions and to better elucidate their biological behavior. MATERIAL AND METHODS: Tissue samples of 15 cases of OSCCs and 15 OEDs were subjected to CD133 antibody immunohistochemistry reactions. The analysis used quantitative parameters (number of immunostained cells regardless of immunostaining sublocations). RESULTS: All samples of OSCCs and OEDs showed positive immunostaining, with no significant difference between these groups (p = 0.283). We did not observe statistical difference between the degree of dysplasia and the amount of CD133+ cells (p = 0.899). CD133 immunoexpression showed no association with the OEDs and OSCCs sites. It was observed that nuclear and cytoplasmic immunostaining was more evident with the progression of the malignant process. CONCLUSION: It is suggested that the CD133 cellular localization together with the histopathological criteria of OEDs classification can contribute to provide more concrete indications about the oral carcinogenesis process.

Immunoexpression of DNA base excision repair and nucleotide excision repair proteins in ameloblastomas, syndromic and non-syndromic odontogenic keratocysts and dentigerous cysts.

OBJECTIVE: To evaluate the immunoexpression of DNA base excision repair (BER) [apurinic/apyrimidinic endonuclease 1 (APE-1), X-ray repair cross complementing 1 (XRCC-1)] and nucleotide excision repair (NER) [xeroderma pigmentosum complementation group (XPF)] proteins in benign epithelial odontogenic lesions with different biological behaviors. DESIGN: Thirty solid ameloblastomas, 30 non-syndromic odontogenic keratocysts (NSOKCs), 29 syndromic odontogenic keratocysts (SKOCs), 30 dentigerous cysts (DCs) and 20 dental follicles (DFs) were evaluated quantitatively for APE-1, XRCC-1 and XPF through immunohistochemistry. RESULTS: Nuclear expression of APE-1 was significantly higher in NSOKCs, SOKCs, and ameloblastomas in comparison to DCs (p < 0.001). Nuclear expression of XRCC-1 was higher in NSOKCs and SOKCs than in DCs (p < 0.05). At the nuclear level, XPF expression was higher in NSOKCs and SOKCs than in DCs and ameloblastomas (p < 0.05). A statistically significant higher expression of APE-1 (nuclear), XRCC-1 (nuclear), and XPF (nuclear and cytoplasmic) was found in all odontogenic lesion samples as compared to DFs (p < 0.05). For all lesions, there was a positive correlation between nuclear expression of APE-1 and XRCC-1 or XPF (p < 0.05). CONCLUSIONS: Our results suggest a potential involvement of APE-1, XRCC-1 and XPF proteins in the pathogenesis of benign epithelial odontogenic lesions, especially in those with more aggressive biological behavior, such as ameloblastomas, NSOKCs, and SOKCs. We also showed that the expression of APE-1 was positively correlated with the nuclear expression of XRCC-1 and XPF, which may suggest an interaction between the BER and NER pathways in all odontogenic lesions studied herein.

A retrospective study of an alternative technique for implant repositioning in the maxillary esthetic region.

BACKGROUND: Implant-bone block segment repositioning may be an option of treatment for patients with vertical alveolar bone atrophy. PURPOSE: To assess implant-bone block movement, gingival outcome and the subjective appreciation of patients after an alternative treatment of an implant-bone block segment repositioning in the maxillary esthetic region. MATERIALS AND METHODS: Patients who underwent implant-bone block segment relocation in areas of vertical alveolar bone atrophy in the anterior esthetic region were assessed. The outcome measures were implant failure, complications after initial loading, vertical bone augmentation, papilla index, width of the keratinized mucosa, and patient satisfaction. RESULTS: Twenty-five implants in nine consecutive patients were included in this study. During the follow-up period, only one implant failed. Vertical bone augmentation ranged from 3.0 to 8.4 mm (mean 4.9 mm). A significant improvement (P < .001) in the papilla index was observed, improving the esthetic outcome. Six patients (66.6%) had more than 2 mm of keratinized mucosa and all of the patients were satisfied with the treatment. CONCLUSIONS: The esthetics and functional gingival outcome of oral rehabilitation in areas with vertical alveolar bone atrophy can be successfully improved with the presented technique, which had a high overall implant survival rate within a short period.