Oral lesions of systemic lupus erythematosus: A collaborative Latin American study.

BACKGROUND: Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease that may affect the oral mucosa. The variable spectrum of oral lesions observed in SLE can pose challenges in diagnosis, particularly when the lesions occur in isolation. The aim of this study was to describe the oral lesions occurring in patients with SLE from Latin America. METHODS: This collaborative record-based study involving 11 oral and maxillofacial pathology and medicine services across Venezuela, Argentina, Chile, Brazil, and Mexico describes the clinicopathological profile of SLE-related oral lesions. RESULTS: Seventy patients with SLE and oral lesions were included in the study. The majority were females (75.7%; female/male ratio: 3.1:1) and white (62.1%), with a mean age of 38.4 years (range: 11-77 years). The most common site of oral lesions was the hard/soft palate (32.0%). Clinically, oral lesions predominantly presented as ulcers (26.6%), erosions (26.6%), and white lesions (23.4%). Isolated oral lesions occurred in 65.2% of individuals, while cutaneous manifestations occurred in 80.3%. The main clinical diagnostic hypothesis in 71.4% of cases was an immune-mediated disease. Oral biopsies followed by histopathological analysis were performed in 50 cases. CONCLUSION: Oral lesions of SLE exhibit a variety of clinical and histopathological features. A key point in diagnosis is that unusual oral changes without an obvious local cause may indicate a possible systemic condition presenting with oral lesions. A multidisciplinary approach, which includes regular oral examination, is warranted to identify oral lesions and provide treatment.

Oral melanoacanthoma: Clinicopathological and immunohistochemical features of a case series and a scoping review.

BACKGROUND: This study presents a case series and scoping review of oral melanoacanthoma to examine its clinical, histopathological, and immunohistochemical characteristics. METHODS: Nine cases of oral melanoacanthoma were included in the case series. Clinical data were collected from biopsy charts. Hematoxylin-eosin and immunohistochemistry for TRP2, CD3, and CD20 were done. For the scoping review, MEDLINE/PubMed, Web of Science, EMBASE, and Scopus were searched. RESULTS: Case series: The mean age was 46.8 years (female-to-male ratio 2:1). Lesion's mean size was 11.0 mm (±9.3). Lesions were mainly macular (77.8%) with brown or black coloration (88.9%) and often affected multiple sites (44.4%). The evolution time ranged from 15 days to 96 months. Lesions commonly showed epithelial acanthosis (66.7%), spongiosis (55.6%), exocytosis (77.8%), melanin incontinence (88.9%), and inflammatory infiltrate in the lamina propria (77.8%), from which all showed lymphocytes. TRP2-positive melanocytes were identified in the basal and spinous layer of all cases, and in the superficial layer of three cases. CD3-positive cells predominate over the CD20-positive. Scoping review: 85 cases of oral melanoacanthoma were retrieved from 55 studies. Patients were primarily female (female-to-male ratio 2.2:1), black-skinned (64.1%), with a mean age of 36.13 (± 17.24). Lesions were flat (81.9%), often brown (62.4%). Buccal mucosa was the preferred site (32.9%), followed by multiple sites (28.2%). CONCLUSION: Oral melanoacanthoma mainly affects women across a wide age range, with lesions commonly appearing as brown/black macules, particularly on the buccal mucosa. TRP2-positive melanocytes and T-lymphocytes were consistently found and could participate in oral melanoacanthoma pathogenesis.

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.

Effects of photobiomodulation with blue Light Emitting Diode (LED) on the healing of skin burns.

The management of skin burns is still challenging. Among the therapeutic methods used, there are topical treatments with pharmacological and herbal agents, low-intensity therapeutic ultrasound, use of biomaterials, reconstructive techniques and photobiomodulation therapy. The aim of this study was to evaluate the effects of photobiomodulation with blue Light Emitting Diode (LED) on burn healing. Fifty Wistar rats were divided into control (CTRL) (n = 25) and blue LED (LED) (n = 25), with subgroups (n = 5) for each time of euthanasia (7, 14, 21, 28 and 32 days). Treated animals were daily irradiated (470 nm, 1W, 0.44 W/cm2, 50 J/cm2). Clinical evaluations were performed and the Wound Retraction Index (WRI) was determined. Histological sections were submitted to hematoxylin-eosin, toluidine blue and the immunohistochemical technique, with anti-α-SMA and anti-TGF-ß1 antibodies. All data were directly collected by previously calibrated evaluators in a blind manner. The values were included in a statistical program. For all statistical tests used, 5% significance level (p < 0.05) was considered. No statistically significant differences in WRI between groups were observed (p > 0.05). Re-epithelialization was higher using LED at 7 and 14 days (p < 0.05) and greater amount of inflammatory cells was observed at 7 days (p = 0.01). With LED at 21 and 32 days, greater number of mast cells were observed (p < 0.05), as well as smaller number of myofibroblasts at 14, 21, 28 and 32 days (p < 0.05) and lower percentage of TGF-ß1 positive cells in the conjunctiva at 7, 14 and 21 days (p < 0.05). Negative correlations were observed in LED between the percentage of TGF-ß1 in the epithelium and the mean number of inflammatory cells and number of myofibroblasts (p < 0.05). The results suggest that, depending on the period, blue LED can modulate the healing processes of third-degree skin burns, such as re-epithelialization, inflammatory response, mast cell concentration, myofibroblast differentiation and TGF-ß1 immunoexpression. Despite these effects, this therapy does not seem to have significant influence on the retraction of these wounds. Future studies, using different protocols, should be carried out to expand the knowledge about the photobiomodulatory mechanisms of this type of light in the healing process.

Role of plasminogen activator inhibitor-1 in oral tongue squamous cell carcinoma: An immunohistochemical and in vitro analysis.

OBJECTIVE: To evaluate the influence of plasminogen activator inhibitor-1 (PAI-1) on the biological behavior and prognosis of oral tongue squamous cell carcinoma (OTSCC). METHODS: Immunoexpression of PAI-1 was analyzed in 60 OTSCC specimens and classified as low-expression (≤50% of positive cells) or high-expression (>50%). In vitro effects of recombinant human PAI-1 (rhPAI-1) were assessed through functional assays on the OTSCC-derived cell line SCC-25. Three cell groups were evaluated: G0 (control), G10 (10 nM rhPAI-1), and G20 (20 nM rhPAI-1). RESULTS: High membrane expression of PAI-1 was associated with tumor budding (p = 0.046) and high-risk cases (p = 0.043). Cytoplasmic and membrane expression of PAI-1 was not associated with patient survival. Cell viability (p = 0.020) and progression to the S-phase of the cell cycle (p = 0.024) were higher in G10 and G20 at 24 h. The percentages of apoptotic/necrotic cells were not affected by rhPAI-1. The presence of rhPAI-1 increased cell migration (p = 0.039) and invasion (p = 0.039) after 24 and 72 h, respectively. CONCLUSION: Our findings indicate the involvement of PAI-1 in the biological behavior of OTSCC, although its expression may not predict patient survival. The in vitro results suggest that PAI-1 stimulates cell proliferation, migration and invasion and may contribute to the aggressive phenotype of OTSCC.

Impact of the COVID-19 pandemic on public University laboratories of oral and maxillofacial pathology: A Brazilian multicenter study.

OBJECTIVE: To evaluate the impact of the COVID-19 pandemic on the number of diagnoses of oral and maxillofacial lesions in public laboratories after one year of COVID-19 outbreak in Brazil. MATERIAL AND METHODS: This is a cross-sectional study. Biopsies submitted to histopathologic examination from March 2019 to February 2020 (pre-pandemic period) and from April 2020 to March 2021 (pandemic period) in nine Brazilian public oral pathology laboratories were retrieved and the number of diagnoses, types of lesion, and percentage changes during both periods were analyzed. RESULTS: There were 7389 diagnoses in the pre-pandemic period and 2728 in the pandemic era, indicating a reduction of 63.08%. The reduction was 64.23% for benign lesions and 49.48% for malignant lesions, with a 50.64% reduction in squamous cell carcinoma. The largest decreases were observed in April 2020 and January 2021. CONCLUSION: An important reduction in the diagnoses of benign and malignant lesions was noted in the Brazilian public oral pathology laboratories during the first year of the COVID-19 pandemic.

Effects of photobiomodulation therapy with red LED on inflammatory cells during the healing of skin burns.

The aim of this study was to evaluate the effects of red light emitting diode (LED) photobiomodulation therapy protocol on inflammatory cells during the healing of third-degree skin burns. Fifty Wistar rats were randomly divided into control group (CTRL) (n = 25) and red group (RED) (n = 25), with subgroups (n = 5) for each time of euthanasia (7, 14, 21, 28, and 32 days). Treatment animals were daily irradiated (630 nm ± 10 nm, 300 mW, 9 J/cm2 per point, 30 s, continuous emission mode) at the 4 angles of the wound (total: 36 J/cm2). After specimen removal, histological sections were stained with hematoxylin and eosin for quantitative analysis of the inflammatory infiltrate (neutrophils and lymphocytes) under light microscopy. Greater number of inflammatory cells was observed in irradiated groups when compared to CTRL at 7, 14, 21, and 28 days, but with statistically significant difference only at 14 days (p = 0.02). At 32 days, higher inflammatory cell value was observed in CTRL when compared to RED, but with no statistically significant difference (p = 0.91). The results suggest that red LED, according to the protocol used, modulates the number of inflammatory cells in the early stages of the healing of third-degree skin burns. Nevertheless, this low-intensity light therapy may not, be efficient in reducing the number of neutrophils and lymphocytes in advanced stages of the repair process of skin burns. Further studies with other therapy protocols are needed to assess the effects of this type of light on the inflammatory response of skin burns.

Absence of multinucleated giant cell reaction as an indicator of tumor progression in oral tongue squamous cell carcinoma.

PURPOSE: The aim of this study was to evaluate the presence and distribution of multinucleated giant cell (MGC) reactions in 61 cases of OTSCC and to verify the association of this microscopic finding with clinicopathological parameters (gender, age, tumor size/extent, regional lymph node metastasis, distant metastasis, clinical stage, and histopathological grade of malignancy). METHODS: Clinical data were collected from medical records and the histopathological grade of malignancy of OTSCCs was evaluated using the World Health Organization (WHO) grading system. The presence and distribution of MGC reaction in high power fields (HPFs) were evaluated in hematoxylin-eosin-stained histological sections. In all cases containing MGCs, immunohistochemical analysis for CD68 was performed in order to confirm the histiocytic nature of these cells. RESULTS: Twenty-one (34.4%) cases had MGC reactions, with a higher frequency of the focal distribution pattern (57.1%). All MGCs were immunohistochemically positive for CD68. The absence of MGC reaction was significantly associated with regional lymph node metastasis (PR: 2.75; 95% CI 1.05-7.20; p = 0.027), advanced clinical stage (PR: 3.37; 95% CI 1.28-8.85; p = 0.006), and moderately/poorly differentiated tumors (PR: 3.36; 95% CI 1.51-7.48; p = 0.001). No significant associations were observed between the distribution of MGCs and clinicopathological parameters (p > 0.05). CONCLUSION: Taken together, the results of this study suggest that the absence of MGC reaction may represent an indicator of tumor progression in OTSCCs.

Analyses of VEGFC/VEGF-D expressions, density and endothelial lymphatic proliferation in salivary gland neoplasms.

OBJECTIVE: The aim of this study was to assess vascular endothelial growth factor C (VEGF-C) and VEGF-D expressions, tumor lymphatic density (D2-40) and endothelial lymphatic proliferation (D2-40/Ki-67 double labeling) in a series of salivary gland neoplasm cases. MATERIALS AND METHODS: Twenty pleomorphic adenomas (PA), 20 adenoid cystic carcinomas (ACC) and 20 mucoepidermoid carcinomas (MEC) were assessed, as well as 10 normal minor salivary gland (SG) tissues for comparison. RESULTS: All cases presented positive VEGF-C expression in the peritumoral and intratumoral regions, and no differences in immunoexpression were detected between groups. However, the ACC group presented a significant difference in VEGF-C immunoexpression according to the predominant histological pattern. Most cases presented poor VEGF-D labeling in the peritumoral and intratumoral regions. Concerning peritumoral, intratumoral and total lymphatic endothelial density, the assessed groups revealed an increasing gradient, with lower values for PA, followed by MEC and ACC. CONCLUSION: No correlation was detected between VEGF-C and VEGF-D immunoexpression in relation to lymphatic tumor density and endothelial lymphatic proliferation. Western blotting (WB) revealed no difference between VEGF-C and VEGF-D expression among the lesions, corroborating the immunohistochemistry findings.

Clinicopathological and immunohistochemical features of the oral lymphoepithelial cyst: A multicenter study.

BACKGROUND: Analyze the clinical, demographic, histopathological, and immunohistochemical features of oral lymphoepithelial cyst (OLEC). METHODS: Samples were retrospectively retrieved from five oral pathology services. Clinical and demographic data were collected from patient charts. Histopathological and immunohistochemical (CD3 and CD20) features were evaluated. Data analysis involved descriptive statistics and bivariate analyses (P ≤ .05). RESULTS: Seventy-seven cases were found among a total of 146 150 specimens (0.05%). OLEC was predominantly diagnosed in females (70.1%). Mean patient age was 46.51 years. The lesions arose mainly on the lateral border of the tongue (40.3%), measured up to 1 cm (61.0%), and were asymptomatic (64.9%). Twenty-four lesions (31.2%) were white. Forty-one cases (53.2%) presented lymphocytic inflammatory infiltrate with no specific arrangement. The cystic lining was composed of a non-keratinized stratified epithelium (59.7%) presenting hyperplasia (39.0%). Connection with the surface, epithelium was found in 23 cases (29.9%) and 31 (40.3%) cases had two or more cystic cavities. The lumen content was predominantly desquamated cells (48.1%). Subgemmal neurogenous plaque was found in 11/42 (26.2%) cases involving the tongue. CD20+ cells predominated in 36/63 cases (57.2%), and lymphocytic inflammatory infiltrate was not always continuous around the cystic cavity (52.4%). CONCLUSION: Lymphoepithelial cyst is an uncommon lesion of the oral cavity. The present study offers the largest sample of OLEC for which clinical, demographic, histopathological, and immunohistochemical features were evaluated. The clinical and demographic findings were similar to those described in previous reports, but the microscopic analyses revealed interesting aspects of the cystic epithelium and the lymphocytic inflammatory infiltrate in OLEC.

Photobiomodulation of red and green lights in the repair process of third-degree skin burns.

The aim of this study was to evaluate the photobiomodulation of red and green lights in the repair process of third-degree skin burns in rats through clinicopathological and immunohistochemical parameters. Sixty male Wistar rats were divided into three groups: control (CTRL) (n = 20), red LED (RED) (n = 20), and green LED (GREEN) (n = 20), with subgroups (n = 5) for each time of euthanasia (7, 14, 21, and 28 days). Daily applications in RED (λ630 ± 10 nm, 300 mW) and GREEN groups (λ520 ± 30 nm, 180 mW) were performed at four points of the wound (total 36 J/cm2 in RED and 240 J/cm2 in GREEN). After euthanasia, the wound retraction index (WRI) was evaluated. In histological sections, the re-epithelialization degree, the angiogenic index (AI), and the amount of myofibroblasts in wounds were analyzed. At 14 and 21 days, the RED group induced higher re-epithelialization and WRI compared to CTRL (p > 0.05) and GREEN groups (p < 0.05). At 7 and 14 days, greater AI were observed in the GREEN group, with significant difference in relation to CTRL group at 7 days (p < 0.05). At 21 and 28 days, a trend was observed for greater amount of myofibroblasts in the GREEN group, with significant difference in relation to CTRL group at 21 days (p < 0.05). The results suggest greater potential of the green light to stimulate angiogenesis in the initial periods and myofibroblastic differentiation in the final periods of the repair of third-degree skin burns. Red light may stimulate further re-epithelialization and wound retraction, especially in advanced repair phases.

Psammoma Bodies in a Large Myoepithelioma.

Myoepithelioma is a rare benign tumor of the salivary glands, in which the vast majority of neoplastic cells are myoepithelial. A rare microscopic finding in salivary gland tumors, including myoepitheliomas, is the presence of psammoma bodies (PBs), whose etiology and role in the tumors are uncertain. The objective of this study is to describe the unusual histopathologic findings, such as psammomas, of a large myopephelioma on the palate and the prosthetic restorative treatment performed after resection of the tumor. A 52-year-old woman was referred for evaluation of a tumor-like lesion, of smooth surface and normal mucosal color, measuring approximately 5 cm, on the left side hard palate, which had been identified 4 years earlier. The diagnostic hypothesis was a pleomorphic adenoma (PA), and an incisional biopsy was performed. After histopathologic analysis, a PA was suggested, and surgical resection of the tumor was performed. The histopathologic findings were compatible with myoepithelioma showing numerous calcified basophilic structures compatible with PB. Sixteen months after resection of the tumor, a removable maxillary obturator prosthesis was made because of the communication into oral and nasal cavity due from the surgical procedure. The treatment of choice for myoepithelioma is surgical excision with a nonlesional area margin. In the present report, the authors achieve good postoperative results without recurrences. After installation of the prosthesis, the patient had an excellent adaptation and acceptance, thus restoring her function and psychologic condition.

Effect of blue LED on the healing process of third-degree skin burns: clinical and histological evaluation.

The aim of this study was to evaluate the effects of blue light-emitting diode (LED) on the healing process of third-degree skin burns in rats through clinical and histological parameters. Forty male Wistar rats were divided into two groups: control (CTR) (n = 20) and blue LED (BLUE) (n = 20), with subgroups (n = 5) for each time of euthanasia (7, 14, 21, and 28 days). LED (470 nm, 1 W, 12.5 J/cm2 per point, 28 s) was applied at four points of the wound (total, 50 J/cm2). Feed intake was measured every other day. It was observed that there were no statistically significant differences in the Wound Retention Index (WRI) of the BLUE group in relation to CTR group (p > 0.05) at the evaluation times. After 14, 21, and 28 days, it was observed that the animals in the BLUE group consumed more feed than animals in the CTR group (p < 0.05). At 7 days, there was a statistically significant increase in the angiogenic index (AI) in BLUE (median: 6.2) when compared to CTR (median: 2.4) (p = 0.01) and all animals in BLUE had already started re-epithelialization. This study suggests that blue LED, at the dosimetry used, positively contributed in important and initial stages of the healing process of third-degree skin burns.

Immunohistochemical analysis of MMP-13 and EMMPRIN in epithelial odontogenic lesions.

PURPOSE: To investigate the contribution of MMP-13 in tumor aggressiveness, by acting on the reorganization of the extracellular matrix, regulating the biological activity of cytokines in odontogenic epithelial lesions, as well as to evaluate the role of EMMPRIN as an inducer of MMP-13. METHODS: Twenty solid ameloblastomas (SAs), 10 unicystic ameloblastomas (UAs), 20 odontogenic keratocysts (OKCs), and 20 adenomatoid odontogenic tumors (OATs) were selected. The expression of MMP-13 and EMMPRIN was evaluated in epithelial/connective tissue by determining the score of immunoreactive cells. RESULTS: Higher concentration of MMP-13 was observed in epithelium of SAs and OKCs (p = 0.316), while in connective, MMP-13 was more expressed in OKCs and UAs (p = 0.213). OKCs exhibited the highest immunoreactivity score for EMMPRIN in the epithelium (p = 0.091). In connective tissue, a larger number of immunoreactive cells were observed in OKCs and UACs (p = 0.357). There was a moderate correlation (r = 0.343/p = 0.004) between MMP-13/EMMPRIN in epithelium and strong correlation (r = 0.474/p < 0.001) in connective tissue. CONCLUSION: We suggest that the OKCs, SAs and UAs presented greater immunoexpression for MMP-13 and EMMPRIN, since they were lesions of more aggressive behavior, with smaller expressions in the AOTs that are admittedly indolent. However, we did not find a statistically significant difference between the expression of MMP-13 and EMMPRIN in lesions studied. The positive correlation found between MMP-13 and EMMPRIN in the epithelial and connective tissue of odontogenic lesions analyzed, seems to be related to the role of EMMPRIN as an inducer of MMP-13 expression.

Immunoexpression of glucocorticoid receptor alpha (GRα) isoform and apoptotic proteins (Bcl-2 and Bax) in actinic cheilitis and lower lip squamous cell carcinoma.

BACKGROUND: Actinic cheilitis (AC) is a potentially malignant disorder that can progress to squamous cell carcinoma (SCC), but this process is not fully understood. This study evaluated the immunoexpression of glucocorticoid receptor alpha (GRα) isoform and apoptotic proteins (Bcl-2 and Bax) in AC and lower lip SCC (LLSCC). METHODS: Twenty-two AC and 44 LLSCCs (22 with regional nodal metastasis and 22 without metastasis) were selected. The percentages of nuclear (GRα) and cytoplasmic (GRα, Bcl-2, and Bax) staining in epithelial cells were assessed and correlated with clinical (tumor size/extent and clinical stage) and histopathological parameters (risk of malignant transformation for AC and histopathological grade of malignancy for LLSCCs). RESULTS: Expression of GRα was observed in all cases studied, with relatively high median percentages of positive staining. When compared to AC, LLSCCs exhibited lower nuclear expression and higher cytoplasmic expression of GRα (P < 0.05). Regarding clinicopathological parameters, significant differences were only found for cytoplasmic expression of GRα according to the histopathological grade of LLSCCs (P = 0.036). Higher expression of Bax compared to Bcl-2 was observed in AC and LLSCCs (P < 0.05). In LLSCCs, there was a positive correlation between nuclear and cytoplasmic expressions of GRα (P = 0.006). CONCLUSION: Reduced nuclear translocation and increased cytoplasmic expression of GRα may be important events in lip carcinogenesis but are not involved in the progression of LLSCC. The role of GRα in lip cancer development does not seem to be primarily related to modulations in the expression of Bcl-2 or Bax.

Expression of matrix metalloproteinases (MMPs-2, -7, -9, and -26) and tissue inhibitors of metalloproteinases (TIMPs-1 and -2) in pleomorphic adenomas and adenoid cystic carcinomas.

PURPOSE: To compare the immunohistochemical expression of matrix metalloproteinases-2, -7, -9 and -26 and tissue inhibitors of metalloproteinases-1 and -2 in pleomorphic adenomas and adenoid cystic carcinomas of the minor salivary glands. METHODS: Twenty cases of pleomorphic adenomas and 20 cases of adenoid cystic carcinomas were evaluated for the immunohistochemical expression of matrix metalloproteinases-2, -7, -9, and -26 and tissue inhibitors-1 and -2 in tumor parenchyma. RESULTS: Most pleomorphic adenomas and adenoid cystic carcinomas showed high expression of matrix metalloproteinases and tissue inhibitors, predominantly located in the tumor cells. There was no statistically significant difference in the expression of the metalloproteinases-2 (p = 0.359), -7 (p = 0.081), and -26 (p = 0 553), as well as the tissue inhibitors-1 (p = 0.657), and -2 (p = 0.248) between the parenchyma of the studied tumors. Only matrix metalloproteinase-9 showed a significant difference in expression between the two tumors, with adenoid cystic carcinoma showing a more intense staining for this gelatinase (p = 0.041). CONCLUSIONS: The expression of the studied metalloproteinases suggests the involvement of these enzymes in the tissue remodeling process in pleomorphic adenomas and adenoid cystic carcinomas, but only MMP-9, significantly expressed in the adenoid cystic carcinomas, appears to be involved in the process of invasiveness and more aggressive behavior of these tumors. Additionally, results point that TIMPs-1 and -2 may have more complex functions besides metalloproteinase inhibition, which may be related to the pathogenesis and biological behavior of salivary gland tumors.

An update of 77 cases diagnosed as oral hemangiomas based on GLUT-1 positivity.

OBJECTIVES: To evaluate cases diagnosed as "oral hemangiomas" based on the immunohistochemical expression of human glucose transporter protein (GLUT-1) and on histopathological features, and to investigate whether the classification proposed by the ISSVA was used correctly to classify these lesions. MATERIAL AND METHODS: All cases stored in the archives of an Oral Pathology Service and diagnosed as "oral hemangiomas" were reviewed. Seventy-seven cases were analyzed regarding the expression of GLUT-1. GLUT-1(+) specimens were classified as true infantile hemangioma (IH) and GLUT-1(-) specimens were reclassified based on their histopathological features. The nomenclature of these lesions was evaluated and some cases were reclassified. RESULTS: Only 26 (33.8%) of the specimens were indeed IHs. Among the GLUT-1(-) specimens, 20 (26.0%) were reclassified as pyogenic granulomas (PGs) and 31 (40.2%) as vascular malformations. Considering the previously applied nomenclature, only 47.5% of the cases initially diagnosed as "hemangiomas" were IHs. In the group of "capillary hemangiomas", most cases (56.2%) were PGs. Among the three "cellular hemangiomas", two were PGs and one was IH. Most (88.8%) "cavernous hemangiomas" were vascular malformations. CONCLUSION: Careful and parameterized review of cases of vascular anomalies is necessary using auxiliary tools such as GLUT-1, since the exclusive use of histopathological findings might be insufficient to differentiate some anomalies. CLINICAL RELEVANCE: Accurate clinical examination and the use of biomarkers such as GLUT-1 are essential for the diagnosis.

Immunohistochemical analysis of myofibroblasts, TGF-ß1, and IFN-γ in epithelial odontogenic lesions.

AIM: To investigate the presence of myofibroblasts (MFBs) in epithelial odontogenic lesions by immunohistochemistry and to correlate the findings with tumor aggressiveness, as well as to analyze the expression of TGF-ß1 and IFN-γ during the differentiation of these cells. METHODS AND RESULTS: Twenty solid ameloblastomas (SAs), 10 unicystic ameloblastomas (UAs), 20 keratocystic odontogenic tumors (KCOTs), and 20 adenomatoid odontogenic tumors (AOTs) were selected. For evaluation of the presence of MFBs, anti-α-SMA-immunoreactive cells were quantified in connective tissue near the epithelium. The expression of TGF-ß1 and IFN-γ was evaluated in epithelial and connective tissue by determining the percentage of immunoreactive cells. A higher concentration of MFBs was observed in SAs (mean of 30.55), followed by KCOTs (22.50), UAs (20.80), and AOTs (19.15) (P = 0.001). There was no significant correlation between the immunoexpression of TGF-ß1 or IFN-γ and the number of MFBs (P > 0.05). CONCLUSIONS: The larger number of MFBs suggests that these cells are one of the factors responsible for the more aggressive biological behavior of these lesions. The lack of correlation between the number of MFBs and immunoexpression of TGF-ß1 and IFN-γ indicates that these proteins are not involved in the differentiation of this type of contractile cell in the lesions studied and that only the use of immunohistochemistry to establish such a correlation is a limiting factor.