Central Mucoepidermoid Carcinoma Radiographically Mimicking an Odontogenic Lesion

Central mucoepidermoid carcinoma (CMEC) is a rare pathological entity with only a few case reports in the literature. The present case reported an uncommon occurrence of CMEC mimicking an odontogenic lesion in a young patient. A 17-year-old female patient sought dental care due to a slight swelling located in the posterior region of the mandible on the left side. Radiographic exams revealed an osteolytic lesion with defined limits in relation to proximity to the pericoronal follicle of tooth #38. The clinical and radiographic diagnostic hypothesis was an odontogenic lesion. Histological sections showed the presence of a neoplasm of glandular origin, not encapsulated, with a predominantly cystic growth pattern. The neoplasm consisted of mucous, intermediate, and squamous cells. In the immunohistochemical staining, the neoplastic cells were positive for cytokeratin 7. Mucous cells were positive for PAS with diastase digestion. The final diagnosis consisted of mucoepidermoid carcinoma. The tumor was removed surgically, and the patient has shown no signs of relapse nor recurrence. In conclusion, CMEC may mimic radiographic features of various pathologies, but despite its rarity, clinicians and oral radiologists should consider CMEC as a diagnostic hypothesis for jaw lesions.

Adenomatoid odontogenic tumor: Features of ameloblastic-like epithelial cells differentiation, secretion, and the nature of tumor cells products

BACKGROUND

This study aimed to investigate the differentiation of ameloblastic-like cells and the nature of the secreted eosinophilic materials in adenomatoid odontogenic tumors.

METHODS

We studied histological and immunohistochemical characteristics of 20 cases using: cytokeratins 14 and 19, amelogenin, collagen I, laminin, vimentin, and CD34.

RESULTS

Rosette cells differentiated into ameloblastic-like cells positioned face-to-face, displaying collagen I-positive material between them. Epithelial cells of the rosettes can differentiate into ameloblastic-like cells. This phenomenon probably occurs due to an induction phenomenon between these cells. The secretion of collagen I is probably a brief event. Amelogenin-positive areas were interspersed by epithelial cells in the lace-like areas, outside the rosettes and distant from the ameloblastic-like cells.

CONCLUSIONS

There are at least two types of eosinophilic material in different areas within the tumor, one in the rosette and solid areas and another in lace-like areas. The secreted eosinophilic material in the rosettes and solid areas is probably a product of well-differentiated ameloblastic-like cells. It is positive for collagen I and negative for amelogenin, whereas some eosinophilic materials in the lace-like areas are positive for amelogenin. We hypothesize that the latter eosinophilic material could be a product of odontogenic cuboidal epithelial or intermediate stratum-like epithelial cells.

Oral epithelial dysplasia grading: comparing the binary system to the traditional 3-tier system, an actuarial study with malignant transformation as outcome

BACKGROUND

Establishing the risk of malignant transformation (MT) in oral leukoplakia is usually based on grading oral epithelial dysplasia (OED) on biopsy tissue, for which two systems are proposed: a 3-tier and a binary system. Only very few actuarial studies have tested the accuracy of such methods in predicting MT, especially for the binary system. This study aimed to assess the accuracy of the two grading systems in predicting MT in a cohort of oral leukoplakia (OL) from Brazil, with follow-up data METHODS: The sample comprised 878 individuals diagnosed with OL from 2005 to 2018. Follow-up data were obtained both locally and from the regional cancer registry. All lesions were graded using both the 3-tier and the binary systems. Kaplan-Meier curves (Log-rank Mantel-Cox) were used to assess risk and kappa to assess interobserver agreement RESULTS: Thirty-five individuals underwent MT (4%). Both systems demonstrated prognostic value, though the 3-tier system proved superior, with OR 9.23 (3.42-23.69), PPV 0.152, NPV 0.98, compared to binary OR 3.49 (1.79-6.79), PPV 0.079, NPV 0.976. Interobserver agreement was also superior in the 3-tier system (0.47, p<0.05) compared to the binary system (0.139, p=0.39). Combining the two systems enhanced prognostic values (OR 14.28, PPV 0.217, NPV 0.981).

CONCLUSION

The 3-tier system presented superior prognostic value to the binary system. Combining both systems to double-grade intermediate lesions might enhance risk assessment.

Primary Intraosseous Synovial Sarcoma in the Mandible

Synovial sarcoma (SS) is a rare malignant mesenchymal tumor that mainly occurs in body extremities, being uncommon in the head and neck region. In the present study, we described a case of primary intraosseous SS arising in the mandible of a 22-year-old young male. The patient reported a painful swelling on the left side of the mandible for the last 7 months. Imaging exams showed the presence of an expansive and multilocular radiolucent lesion, extending from the left condyle to the mandibular body. The clinic diagnostic hypotheses were ameloblastoma or malignant neoplasm. Histologically, the lesion was characterized by a proliferation of spindle cells exhibiting vesicular nuclei and evident nucleolus. Neoplastic cells were positive for AE1/AE3, cytokeratin 7, vimentin, CD-99, and TLE-1 and negative for CD-34, S-100, SMA, and HHF-35. A combination of clinical, histologic, and immunohistochemical characteristics supported the diagnosis of SS. The patient was referred for treatment, and preoperative exams did not reveal any other tumor foci in the body of the patient. The final diagnosis was of a primary intraosseous SS of the mandible.

Autophagy upregulation may explain inhibition of oral carcinoma in situ by photobiomodulation in vitro

There is currently no clear understanding on the pathways involved in the process of cell inhibition by photobiomodulation (PBM). The present study evaluated the influence of PBM on the expression of autophagy markers in vitro in an in situ model of oral carcinoma. Oral squamous cell carcinoma (Cal27) and stromal fibroblasts (FG) cultures were used. The independent variables were 'cell type' (FG and CAL27) 'culture condition' (monocultures or co-cultures) and PBM (placebo and 36 J/cm²). The cultures were irradiated from a red LED source for mRNA expression and protein expression analyses. The autophagy markers evaluated were Beclin-1, LC3B and p62 as well as adjuvant markers (BAX Bcl-2, VEGF, CD105, CD34, PRDX1, PRDX4 and GRP78). The Cal27 cells upregulated the autophagy markers upon exposure to PBM both at the mRNA and protein expression levels, providing evidence to explain malignant cell inhibition by PBM.

Uncommon Pigmented Carcinoma In Situ: Case Report and Brief Review

Pigmented lesions of the oral mucosa encompass several benign and malignant conditions that may be a matter of concern under both clinical and histopathological views. We reported a case of a 62-year-old woman, presenting with an asymptomatic, deeply pigmented lesion on the soft palate. On examination, it appeared asymmetrical, with irregular borders and an area of ulceration. A biopsy, taken to rule out melanoma, revealed a pigmented carcinoma in situ. Throughout the tumor thickness, numerous interspersed melanocytes were found that did not extend to neighboring epithelium. These were large, richly dendritic, and presented abundance of melanin granules and small nuclei. Mild melanin incontinence was found. Scanty transfer of pigment to dysplastic epithelial cells was found through Fontana Masson staining. On immunohistochemical analyses, there were pancytokeratin-stained tumor epithelial cells; increased cell proliferation throughout the entire thickness of the tumor was emphasized by Ki-67 immunomarking. P16 was negative. The dendritic cells were selectively stained for S-100, HMB45 and Melan A. Wide spectrum in situ hybridization for human papillomavirus (HPV) was negative. Unfortunately, following diagnosis, the patient refused any treatment option. Pigmented squamous cell carcinoma with melanocyte colonization must be taken into account in the differential diagnosis of pigmented lesions of the oral cavity.

Expression of invadopodia markers can identify oral lesions with a high risk of malignant transformation

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor of the oral cavity and is usually preceded by a range of premalignant tissue abnormalities termed oral potentially malignant disorders. Identifying malignant transformation is critical for early treatment and consequently improved survival and decreased morbidity. Invadopodia (INV) are specialized subcellular structures required for cancer cell invasion. We developed a new method to visualize INV in keratinocytes using fluorescent immunohistochemistry (FIHC) and semi‐automated images analysis. The presence of INV was used to determine the risk of malignant transformation. We analyzed 145 formalin‐fixed, paraffin‐embedded (FFPE) oral biopsy samples from 95 patients diagnosed as nondysplastic, dysplastic, and OSCC including 49 patients whose lesions transformed to OSCC (progressing) and 46 cases that did not transform to OSCC (control). All samples were stained for Cortactin, tyrosine kinase substrate with five SH3 domains (Tks5) and matrix metallopeptidase 14 (MMP14) using FIHC, imaged using confocal microscopy and analyzed using a multichannel colocalization analysis. The areas of colocalization were used to generate an INV score. Using the INV score, we were able to identify progressing lesions with a sensitivity of 75–100% and specificity of 72–76%. A positive INV score was associated with increased risk of progression to OSCC. Our results suggest that INV markers can be used in conjunction with the current diagnostic standard for early detection of OSCC.

Estrogen Receptor, Progesterone Receptor, and HER-2 Expression in Recurrent Pleomorphic Adenoma

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm and, although mostly benign, recurrences, being called recurrent pleomorphic adenoma (RPA) and malignant transformation to carcinoma ex pleomorphic adenoma (CXPA), do occur. Recently, attention has been focused on molecular targeted cancer therapy in various tumors, including salivary gland tumors. The aim of this study was to investigate the role of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) in PA, RPA, and CXPA. In total, 20 cases of PA, 18 of RPA, and 7 cases of CXPA were immunohistochemically studied for ER, PR, and HER-2. For evaluation of ER and PR, only nuclear expression and greater than 10% positive cells were regarded as cutoff criteria. HER-2 was evaluated semiquantitatively and graded from 0 to 3+. HER-2 amplification was assessed by chromogenic in situ hybridization (CISH). Tumors were negative for ER, PR, and HER-2 in all cases of PA and RPA. A case of CXPA showed moderate and complete membranous staining, and 6 cases were negative. HER-2 amplification was not observed in any case. In conclusion, the lack of ER, PR, and HER-2 expression in PA, RPA, and CXPA suggests that these proteins are not involved in progression, recurrence, or malignant transformation of PA.

MiR-455-3p, miR-150 and miR-375 are aberrantly expressed in salivary gland adenoid cystic carcinoma and polymorphous adenocarcinoma

BACKGROUND

Adenoid cystic carcinoma (AdCC) and polymorphous adenocarcinoma (PAC) are included among the most common salivary gland cancers. They share clinical and histological characteristics, making their diagnosis challenging in specific cases. MicroRNAs (miRNA) are short, non-coding RNA sequences of 19-25 nucleotides in length that are involved in post-transcriptional protein expression. They have been shown to play important roles in neoplastic and non-neoplastic processes and have been suggested as diagnostic and prognostic markers.

METHODS

This study, using quantitative RT-PCR, investigated miR-150, miR-455-3p and miR-375 expression, in order to identify a possible molecular distinction between AdCC and PAC.

RESULTS

miRNA-150 and miRNA-375 expression was significantly decreased in AdCC and PAC compared with salivary gland tissue controls, whilst miRNA-455-3p showed significantly increased expression in AdCC when compared to PAC, (P < 0.05). miR-150, miR-357 and miR-455-3p expression in AdCC, PAC and control was not associated with age, gender nor with anatomic site (major and minor salivary glands) (P > 0.05).

CONCLUSION

MiR-455-3p could be used as a complimentary tool in the diagnosis of challenging AdCC cases.

Dermal vasculature and melanocytic proliferation index in photodamaged skin in the assessment of lateral margins of lentigo maligna and lentigo maligna melanoma

Lentigo maligna (LM) is the most common subtype of melanoma on the face. When it invades the dermis it is called lentigo maligna melanoma (LMM). Its histological delimitation is controversial due to subjectivity. Analysis of peritumoral vasculature and proliferation index of melanocytes may help to differentiate tumor areas from tumor-free areas, as neoplasia-induced angiogenesis in such scenarios, as well as the higher proliferation index of melanocytes in melanomas, are well established. This work compares the peritumoral vasculature and melanocyte proliferation index of LM and LMM with that of adjacent non-neoplastic skin and sun-damaged skin (control). Forty-three resection cases of LM and LMM were selected retrospectively. Immunohistochemistry was performed for anti-CD31 and anti-CD105 to assess vascularization. Melanocyte proliferation index double labeling was performed using the anti-Melan-A and anti-Ki-67. The Chalkley optical grid was used to quantify blood vessel hotspots. Doubly labeled cells with anti-Melan-A and anti-Ki-67 were counted at tumor, free margin, and control skin. Microvasculature quantification under the melanomas, for both CD31 and CD105, was greater than at the margins of the same specimens (P < 0.0001; P = 0.0001) and greater than control skin (P = 0.0016; P = 0.0027), with higher density for CD31 than CD105. The mean number of double-labeled proliferating melanocytes at the melanoma periphery was greater than at the adjacent free skin and control skin (P = 0.0011). The control skin samples showed the highest CD31-positive vasculature in the head and neck region, with a positive correlation between melanocytic proliferation index and vasculature. The presence of neovascularization (CD105) and proliferating melanocytes (Ki67+/Melan-A+) are suspicious findings for LM/LMM, helping to outline, diagnose, and evaluate tumor margins.

Microvessel density and cell proliferation in juvenile ossifying fibroma: A comparative study with central ossifying fibroma

Considered as an aggressive counterpart of central ossifying fibroma (OF), juvenile ossifying fibroma (JOF) is a benign fibro-osseous neoplasm characterized by an unpredictable destructive behavior, elevated morbidity, mutilating treatment and high potential for local recurrences. The aim of this study is to compare the analysis for cell proliferation and vascular markers between JOF and OF. Cell proliferation index was measured by Ki-67 and Mcm-2 expression and microvessel density (MVD) was obtained by the immunoexpression of CD34/CD105. We observed a reduced expression of vascular markers, where MVD for CD34 was significantly higher in JOF than in OF (p = 0.009), but no statistical difference was found for CD105. JOF and OF showed low expression for Ki-67 and Mcm-2 and no difference was noted between both, suggesting that other mechanisms such as anti-apoptotic and/or pro-autophagic pathways or even increased expression of matrix metalloproteinases may be responsible for the aggressiveness of JOF.

Microvessel Density Evaluation of the Effect of Enamel Matrix Derivative on Soft Tissue After Implant Placement: A Preliminary Study

Enamel matrix derivative (EMD) is commonly used in periodontal therapy and has been used successfully for periodontal regeneration. In addition, this material has a possible angiogenic effect that has been associated with enhanced wound healing. The aim of this study was to evaluate the effect of EMD on microvessel density (angiogenesis) on the soft tissues surrounding newly placed implants after 14 days. Five patients were selected, each requiring at least one implant on each side of the maxilla, in a split-mouth experimental design. The implants were placed in a two-stage procedure. Each side was then randomized as test or control. On the test side, 0.1 mL of EMD was topically applied to the soft tissues surrounding the implants, while the control side did not receive any treatment. Second-stage surgery was performed after 14 days. A 6-mm punch biopsy was performed for each implant, with the samples subsequently prepared for histology and immunohistochemistry. Quantitative vascularization analysis was performed, which involved counting three areas or "hotspots" containing vessels strongly positive for CD34 and CD105, a pan-endothelial and new vessel marker, respectively. There was no significant difference between test and control groups when evaluating the formation of new blood vessels. The total number of blood vessels, however, was significantly higher in the group treated with EMD (test group). Within the limits of the present study, it can be concluded that topical application of EMD on the soft tissues surrounding newly placed implants resulted in an increased number of blood vessels at 14 days, suggesting that EMD may play a beneficial role in this aspect of wound healing.

A Combined Epithelial Odontogenic Tumor? A 7-Year Follow-Up Case

Adenomatoid odontogenic tumor (AOT) is a benign epithelial odontogenic tumor characterized by slow and progressive growth. When central lesions are associated with an unerupted permanent tooth, they are also known as the follicular type. Histological variants of AOT may complicate diagnosis with possible adverse effects on treatment and prognosis. The aim of this study is to report a case of a follicular AOT with extensive calcifying epithelial odontogenic tumor (CEOT)-like histopathological areas in the anterior region of the mandible that was treated by enucleation. The teeth displaced by the tumor were repositioned with orthodontic treatment, and after 7 years of follow-up, the bone trabeculae were normal with no evidence of recurrence. The clinical, radiographic and histopathologic aspects of these tumors are discussed and the debate surrounding whether these cases are true combined lesions or histologic variants of the primary tumor is raised.

Solitary fibrous tumor of the hard palate: a rare entity in oral cavity

A case of solitary fibrous tumor is reported. Solitary fibrous tumor is a rare neoplasia characterized by the proliferation of fusiform cells of mesenchymal origin accounting for at least 2% of all soft tissue tumors. In this present case, the initial diagnosis was salivary gland tumor because of the location in the hard palate. Histologically, the tumor was composed by conjunctive tissue with proliferation of oval and fusiform cells. The immunohistochemical analysis was positive for CD34 and CD99. The lesion was treated by surgical resection. The clinical, imaging, histological and immunohistochemical data are discussed in this study.  KeywordsSolitary fibrous tumor; Oral cavity; Hard palate; Differential diagnosis. 

Immunoexpression of growth factors and receptors in polymorphous low-grade adenocarcinoma

BACKGROUND

Polymorphous low-grade adenocarcinoma (PLGA) is a rare malignant tumor that usually arises in the minor salivary glands. Growth factors are cell-secreted peptides that regulate biological processes such as growth, proliferation, and differentiation. In salivary gland tumors, immunoexpression of growth factors and their receptors is associated with cell proliferation, malignant transformation, and tumor invasion. This study analyzed the expression of growth factors and receptors in PLGA, in other to better understand the mechanisms involved in the process of neoplastic cell proliferation and tumor progression.

METHODS

The expression of growth factors FGF-2, PDGF-A, PDGF-B and receptors FGFR-1, FGFR-2, PDGFR-α, and EGFR was analyzed in 24 PLGA samples in comparison with normal salivary glands, by immunohistochemistry. A semi-quantitative analysis determined cell positivity in all stained sections. Scores were assigned according to percentage of reactive cells: score 0 < 10%; score 1-10 to 25%; score 2-25% to 50%; score 3->50%. The level of significance was set at 5%.

RESULTS

Most of the growth factors and receptors, apart from FGFR-2, were significantly reactive in PLGA. Comparing to salivary acini, all of the reactive growth factors and receptors were significantly stronger in PLGA. Comparing to salivary ducts, the expression of FGF-2, PDGF-B, FGFR-1, and EGFR was significantly stronger in the nuclei and/or cytoplasm of the neoplastic cells.

CONCLUSIONS

The increased expression of the growth factors and receptors in the PLGA, compared to normal salivary glands, may be related to cell proliferation, somehow participating in the oncogenic process.

Dysregulation of the Rb pathway in recurrent pleomorphic adenoma of the salivary glands

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm, and while mostly benign, recurrences (RPA) and malignant transformation to carcinoma ex-PA (CXPA) do occur. Cell cycle proteins important in its tumorigenesis have been studied as markers for PA with a high risk of RPA or CXPA. The aim of the present study was to investigate cell cycle markers p-16, cyclin D1, CDK4, E2F, and retinoblastoma (Rb) in this context. Expression of p16, cyclin D1, E2F, CDK4, and Rb was studied by immunohistochemistry in 24 cases of PA, 21 of RPA, and 2 of CXPA. The presence of HPV was assessed by in situ hybridization. Immunostaining for p16 and cyclin D1 was negative or weakly positive in most cases of PA while strongly positive in the majority of RPA and both CXPA cases. Staining for Rb and CDK4 was either negative or weakly positive in PA, RPA, and CXPA. Expression of E2F was stronger in RPA and CXPA than in PA. Nuclear reactivity for HPV was not observed in any case. In conclusion, the strong staining for p16, cyclinD1, and E2F in RPA and CXPA, while weak or negative in PA, suggests that these proteins might be involved in recurrence and malignant transformation of PA.

Comparison of the blood and lymphatic microvessel density of pleomorphic adenoma and Basal cell adenoma

BACKGROUND

Pleomorphic adenoma (PA) is the most common tumor of the salivary gland, while basal cell adenoma (BCA) is an uncommon neoplasm. Blood and lymphatic vessels are crucial for tumor metabolism. The aim of this study was to compare the blood and lymphatic vascular density and vascular and endothelial growth factor (VEGF) expression in PA and BCA tumors. In addition, cell proliferation was evaluated in these tumors.

METHODS

Blood and lymphatic vessel content, VEGF expression, and cell proliferation were analyzed in 30 cases of PA and 13 cases of BCA by immu-nohistochemistry using antibodies for CD34, CD105, D2–40, VEGF, and Mcm−2.

RESULTS

Regarding CD34 and CD105 expression, PA demonstrated a high vascularity and a low number of positive vessels, respectively. D2–40-positive lymphatic vessels were mainly located in the tumor capsules, with small intratumoral lymphatic vessels observed occasionally. VEGF expression revealed a remarkably heterogeneous immunoreactivity, alternating from weak or negative to positive or intense. BCA presented significantly higher CD34, CD34, CD105, D2–40, and VEGF expression compared to PA. No significant difference was found in cell proliferation between the tumors.

CONCLUSION

Although PA and BCA are considered part of the same spectrum of differentiation, this study showed that the blood and lymphatic vascularization of these tumors is different.

Neutrophils in oral paracoccidioidomycosis and the involvement of Nrf2

Neutrophils have been implicated in granuloma formation in several infectious diseases, in addition to their main phagocytic and pathogen destruction role. It has been demonstrated that Nrf2 regulates antioxidant protection in neutrophils, attenuating inflammation without compromising the hosts bacterial defense. In this study, we analyzed the presence of neutrophils in Paracoccidioides brasiliensis mycosis (PCM), as well as the immunoexpression of Nrf2. Thirty-nine cases of oral PCM were classified according to quantity of fungi and to the presence of loose or well-organized granulomas and microabscesses. An Nrf2 antibody was used for immunohistochemical analysis. The results showed that neutrophils are present in microabscesses and loose granulomas, but were absent in structured granulomas. A greater quantity of fungi was shown in cases with only loose granulomas when compared to loose and well organized granulomas. Nrf2 was observed in the nuclei of neutrophils of loose granulomas and abscesses, with its expression in loose granulomas maintained despite the additional presence of well organized granulomas in the same specimen. This study suggests that neutrophils participate in P. brasiliensis granuloma formation and that Nrf2 has a possible role in neutrophil survival, via modulation of the inflammatory response.

Polymorphous low-grade adenocarcinoma: an analysis of epidemiological studies and hints for pathologists

Background

This study is an analysis of the prevalence of polymorphous low grade adenocarcinoma (PLGA) in epidemiological surveys of salivary tumors published in the English language from 1992 to 2012.

Methods

These surveys included studies from different researchers, countries and continents. The 57 surveys for which it was possible to calculate the percentage of PLGAs among all malignant minor salivary gland tumors (MMSGT) were included in this review.

Results

The statistical analyses show significant differences in the PLGA percentage by time period, country and continent in the studies included in this review. The percentage of PLGAs among MMSGTs varied among the studies, ranging from 0.0% to 46.8%. PLGA rates have varied over the period studied and have most recently increased. The frequency of reported PLGA cases also varied from 0.0% to 24.8% by the country in which the MMSGT studies were performed. The PLGA percentages also varied significantly by continent, with frequencies ranging from 3.9% in Asia to 20.0% in Oceania

Conclusion

Based on these results, we concluded that although the accuracy of PLGA diagnoses has improved, they remain a challenge for pathologists. To facilitate PLGA diagnoses, we have therefore made some suggestions for pathologists regarding tumors composed of single-layer strands of cells that form all of the histological patterns present in the tumor, consistency of the cytological appearance and uniformly positive CK7, vimentin and S100 immunohistochemistry, which indicate a single PLGA phenotype.

Virtual slide

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1059098656858324

The increased PDGF-A, PDGF-B and FGF-2 expression in recurrence of salivary gland pleomorphic adenoma

BACKGROUND

Pleomorphic adenoma (PA) is the most common salivary gland tumour. Although classified as benign, it has a tendency to recur (recurrent pleomorphic adenomas (RPA)), as well as the ability to undergo malignant transformation. It has been suggested that mutations in various families of growth factors and growth factor receptions are involved in the autonomous growth of tumour cells. The aim of the present study was to investigate the participation of platelet-derived growth factor (PDGF)-A, PDGF-B, PDGF-Rα, fibroblast growth factor (FGF)-2, Flg and BEK in PA, RPA and recurrent pleomorphic adenoma with malignant transformation (TRPA).

METHODS

18 cases of PA, 16 cases of RPA and two cases of RPA with focal malignant transformation (TRPA) were analysed for growth factor expression utilising immunohistochemical techniques via tissue microarray.

RESULTS

There was a significant difference in PDGF-A, PDGF-B, PDGF-Rα, FGF-2, Flg and BEK expression in all groups. When comparing non-recurrent with recurrent tumours, PDGF-A, PDGF-B, PDGF-Rα, FGF-2, Flg and BEK reactivity in RPA was stronger than that observed in PA. All proteins were highly expressed in TRPA.

CONCLUSIONS

This research suggests that PDGF-A, PDGF-B, PDGF-Rα, FGF-2, BEK and Flg can be related to the recurrence of PA. In addition, this study shows that TRPA cells overexpress all growth factors, which has been reported in association with the malignant transformation.

Increased mucin 1 expression in recurrence and malignant transformation of salivary gland pleomorphic adenoma

AIMS

Pleomorphic adenoma (PA) is the most common salivary gland tumour with a tendency to recur (RPA) and a risk of malignant transformation. Mucin 1 (MUC-1) plays a role in the progression of many tumours and may be a marker to predict RPA. The aim of this study was to evaluate MUC-1 expression in different phases of the adenoma to carcinoma sequence.

METHODS AND RESULTS

Twenty-one cases of PA, 18 cases of RPA, three cases of RPA with focal transformation (TRPA) and 11 cases of carcinoma ex-pleomorphic adenoma (CXPA) were analysed immunohistochemically for MUC1 expression using an antibody to MUC1/DF3. MUC1 reactivity in RPA was stronger than that observed in PA and, in all the different carcinoma groups, MUC-1 expression was significantly higher in carcinoma than in RPA and PA.

CONCLUSION

This study has confirmed that MUC-1 is related to the recurrence of PA and that this molecule is associated with malignant transformation of PA with carcinoma cells overexpressing MUC-1.

Metastatic adenocarcinoma of the colon: early manifestation in gingival tissue

A case of gingival metastasis of adenocarcinoma of the colon is reported, the lesion being an early clinical indication of a primary malignant tumor. The diagnosis of metastatic lesion in the oral region is always challenging, both to clinician and to the pathologist, due to its rarity and complexity. In the present case, the clinical hypothesis was peripheral ossifying fibroma or pyogenic granuloma. Histologically, the biopsy tissue revealed a malignant neoplasm not connected to the mucosal surface. Immunohistochemically, the lesion was positive for 35ßH11 and cytokeratin 20 and focally positive for cytokeratin 7. Treatment involved excision of primary tumor and follow-up chemotherapy. The clinical, histological and immunohistochemical characteristics are discussed.

Study of histopathological, morphological and immunohistochemical features of recurrent pleomorphic adenoma: an attempt to predict recurrence of pleomorphic adenoma

BACKGROUND

Recurrent pleomorphic adenoma (RPA) is an uncommon and challenging disease. The aim of this study was to review the clinical information obtained by examining RPA patients, to determine its histomorphological features and to verify the expression of the Mcm-2 markers of cell proliferation and the expression of p-53 in pleomorphic adenoma (PA), RPA, and RPA with malignant transformation (TRPA).

METHODS

A total of 10 cases of PA and 29 cases of RPA were examined in detail for the presence of nodules and their histomorphological features. Cell proliferation and expression of p-53 were detected by the immunohistochemical technique using the antibodies against Mcm-2 and p-53.

RESULTS

Histopathologically, RPA is very similar to PA; the only difference found was that all the cases of RPA were multinodular. When comparing primary and recurrent tumor, no significant difference was found in terms of cell proliferation and the expression of p-53; however, in the RPA with areas of malignant transformation there was an increased expression of these proteins.

CONCLUSION

This study showed that recurrences were multinodular, with nodules varying in numbers and sizes. No significant difference in histological features was found between RPA and PA. Moreover, the immunohistochemical study showed a low expression of p-53 and Mcm-2 in PA and RPA and an increased expression of these proteins in the RPA with areas of malignant transformation.

Study of growth factors and receptors in carcinoma ex pleomorphic adenoma

Carcinoma ex pleomorphic adenoma (CXPA) is a rare malignant salivary gland tumor derived from a pre-existing pleomorphic adenoma. It is a good model to study the evolution of carcinogenesis, starting with in situ areas to frankly invasive carcinoma. Growth factors are associated with several biological and neoplastic processes by transmembrane receptors. In order to investigate, by immunohistochemistry, the expression of some growth factors and its receptors [EGF receptor, fibroblast growth factor, fibroblast growth factor receptor 1, fibroblast growth factor receptor 2, hepatocyte growth factor, c-Met, transforming growth factor (TGF) beta1, TGFbetaR-II and insulin-like growth factor receptor 1] in the progression of CXPA, we have used ten cases of CXPA in several degrees of invasion- intracapsular, minimally and frankly invasive carcinoma- with only epithelial component. Slides were qualitatively and semi-quantitatively evaluated according to the percentage of stained tumor cells from 0 to 3 (0 = less than 10%; 1 = 10-25%; 2 = 25-50%; 3 = more than 50% of cells). Malignant epithelial cells starting with in situ areas showed stronger expression than luminal cells of pleomorphic adenoma for all antibodies. Most of the intracapsular, minimally and frankly invasive CXPA presented score 3. However, score 2 was more evident in the frankly invasive one. In small nests of invasive carcinoma, negative cells were observed probably indicating that the proliferative process is replaced by the invasive mechanism. Altogether this data infers that these factors may contribute to cell proliferation during initial phases of the tumor.

Intravascular papillary endothelial hyperplasia: report of 2 cases and immunohistochemical study

Intravascular papillary endothelial hyperplasia (IPEH) is a benign, nonneoplastic, vascular lesion. The main significance of the lesion lies in the fact that it may be mistaken for angiosarcoma. Oral lesions are uncommon and the present paper reports 2 cases of oral IPEH, in different sites. Histologically, the tissue was characterized by papillary fronds lined by proliferating endothelium. Immunohistochemically (IHC), the lesion was positive for CD34, smooth muscle actin (SMA), type I and IV collagen, vimentin, and laminin, but it was negative for CD105. Local excision was the treatment of choice. No recurrence was observed during a 1-year and 6-month follow-up period, respectively. The clinical, histological, and immunohistochemical characteristics are discussed.

Expanded Milan criteria on pathological examination after liver transplantation: analysis of preoperative data

BACKGROUND

We sought to evaluate the accuracy of imaging techniques related to the Milan criteria (MC) compared with the explant histology and the survival of these patients.

METHODS

Between 1997 and 2006, we selected 45 cirrhotic patients with hepatocellular carcinoma distributed into two groups according to explant histology: MC and Expanded Milan Criteria (EMC). Age, gender, preoperative imaging (ultrasound [US] and/or computed tomography [CT]), maximal tumor dimension, number of tumors, explanted histology, histology degree, alpha-fetoprotein (AFP) level and vascular invasion were compared among the patients to evaluate the value of these prognostic factors for survival after liver transplantation.

RESULTS

By histology 42.2% explants were identified as EMC. The mean AFP level was 204.5 ng/mL. Vascular invasion was detected in 31.5% of explants and 68.4% showed incidental tumors. The survival rates after 10 years were 47.4% whereas MC patients showed 57.77%. The mean AFP level among MC patients was 150.2 ng/mL with vascular invasion detected in 7.7% of explants, and 47.4% with incidental tumors. The overall sensitivity of the imaging techniques was 83.3% for CT and 75% for US. The specificity was 96% for CT and 80.1% for US.

CONCLUSION

Scan examinations in the preoperative evaluation underestimated about 42.2% of tumors. Those patients had vascular invasion but the survival after 10 years was similar between the ECM and MC groups.

Angiogenic switch during tumor progression of carcinoma ex-pleomorphic adenoma

We analyzed the tumor vascularization in carcinomas ex-pleomorphic adenoma (CXPA) to investigate the angiogenic switch during the malignant transformation of pleomorphic adenoma (PA) to carcinoma and during tumor progression. In eight cases of early CXPA (intracapsular and minimally invasive tumors), eight of advanced CXPA (widely invasive tumors), and ten of PA without malignant transformation, tumor vascularization was assessed in histological samples by measuring total microvascular area (TVA) and microvessel density (MVD) using CD34 and CD105 antibodies. MVD for CD105 increased significantly during tumor progression, whereas this was not the case for CD34 MVD. Comparing widely invasive CXPA with and without myoepithelial differentiation, CXPA with myoepithelial differentiation showed a significantly lower number of CD105 positive vessels but revealed higher TVA values. In these tumors, the neoplastic cells usually formed larger hypovascularized aggregates that were often surrounded by large-sized vessels. In conclusion, the antibody CD105 reveals an angiogenic switch during the progression from adenoma to carcinoma in salivary glands. The degree of angiogenesis and the total vascular area have distinctive patterns in CXPA with and without myoepithelial differentiation. Low angiogenesis associated with high TVA value is more characteristic of CXPA with myoepithelial differentiation.

Lymphatic vascular density and lymphangiogenesis during tumour progression of carcinoma ex pleomorphic adenoma

AIMS

To assess lymphatic vascular density (LVD) and lymph vessel endothelial proliferation in a series of carcinoma ex pleomorphic adenoma (CXPA) that represents the tumour in the different carcinogenesis phases and tumour progression.

METHODS

In 8 cases of early CXPA (intracapsular and minimally invasive tumours), 8 of advanced CXPA (widely invasive tumours) and 10 of pleomorphic adenoma (PA) without malignant transformation, lymphatic vessels and proliferating cells were detected using the antibodies D2-40 and Ki-67 respectively.

RESULTS

Comparing early tumours with advanced ones, LVD was not significantly different at the tumour margin. In contrast, regarding intratumoural lymphatics, PA without malignant transformation and early CXPA contained rare, if any, lymph vessels, whereas in widely invasive carcinomas they were more numerous. However, neither intratumoural nor peritumoural LVD were increased in comparison to adjacent normal salivary gland tissue. In no case did dual immunohistochemistry using D2-40 and the cell proliferation marker Ki-67 reveal the existence of proliferating lymphatics. Carcinomatous emboli were found in peritumoural as well as in intratumoural lymphatics only in advanced CXPA without myoepithelial differentiation.

CONCLUSION

In CXPA, the lymphatic network is mainly composed of pre-existing lymphatics which are rare in tumours that have not infiltrated outside the confines of the original PA. In the widely invasive CXPA, intratumoural as well as peritumoural lymphatics are a conduit for carcinoma cells, but in carcinomas with myoepithelial differentiation, the neoplastic cells seem to have a lower invasion capacity.

Fibrosarcoma originating in the mandible

Fibrosarcoma is a malignant mesenchymal neoplasm of fibroblasts that rarely affects the oral cavity and can cause local recurrences or metastasis. In this article we describe a case of primary fibrosarcoma in the mandible in a 16-year-old girl. Microscopically the tumor showed an intense proliferation of spindle-shaped cells, varying little in size and shape and arranged in parallel bands, partly crossing each other, the mitotic activity was increased and there was nuclear pleomorphism. Immunohistochemically the cells only showed immunoreactivity for vimentin and negativity for S-100 protein, CD 68, cytokeratin cocktail, HMB-45, CD34, pan actin HHF 35, desmin, smooth muscle actin and epithelial membrane antigen (EMA). Based on clinical, radiological, histological and immunohistochemical findings the final diagnosis was high-grade intra-osseous fibrosarcoma. The treatment choice was radical surgery with mandibular reconstruction. After one year and nine months of the treatment the patient displayed multiple metastases. Radiation therapy and chemotherapy were used as adjuvant treatment. Unfortunately, the girl died two years after initial diagnosis.

Chronic GVHD in minor salivary glands and oral mucosa: histopathological and immunohistochemical evaluation of 25 patients

BACKGROUND

Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells.

METHODS

Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining.

RESULTS

The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands.

CONCLUSIONS

Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease.

Primary aspergillosis affecting the tongue of a leukemic patient

We describe a case of primary aspergillosis involving the tongue of a patient with acute myeloid leukemia. Intraoral aspergillosis is very rare and we found only 23 cases reported in the English literature. Clinically it was a 2-cm, ulcerated, grayish lesion on the dorsum of the tongue. Microscopically there was invasion of the epithelium, connective tissue and muscle of the tongue by fungal hyphae branching at 45 degrees angle. The large hyphae were easily seen by H & E stain, and were strongly positive for periodic acid-Schiff and Grocott methenamine. The patient was successfully treated with intravenous amphotericin B. Based on clinical, microscopic and culture data, the diagnosis of primary aspergillosis of the tongue was established. Invasive oral aspergillosis is a potentially lethal disease and it should be considered in immunosuppressed patients.

A morphological and tensile bond strength evaluation of an unfilled adhesive with low-viscosity composites and a filled adhesive in one and two coats

OBJECTIVE

The purpose of this study was to measure the tensile bond strength (TBS) testing of resin composite to dentin of three low-viscosity composites, in association with an unfilled adhesive, and a filled adhesive one and two coats respectively, and to evaluate and compare the SEM morphological observations.

METHODS

The labial surface of 120 bovine lower incisors were ground to obtain a flat dentin surface allowing demarcation of a 4 mm diameter area with adhesive tape. The teeth were randomly divided in six groups of 20 each. The dentin of each ground surface was etched with 35% H(3)PO(4) for 15s, followed by application of the respective adhesive: Single Bond (SB) for Groups 1, 2, 3 and 6; Optibond Solo (OS) for Groups 4 and 5. In Groups 1 and 4, a resin composite rod with a wire loop was luted directly to the adhesive surface with Z100. Group 2 received an intermediate layer of Flow It (FI) composite; Group 3 received an intermediate layer of Protect Liner F (PLF) composite; Group 5 received a second coat of OS; and Group 6 received an intermediate layer of an experimental low-viscosity composite (EM). A resin composite rod was luted to the surface of each specimen with Z100 resin composite. All specimens were stored in distilled water at 37 degrees C for 24h prior to TBS testing. Each specimen was inspected by SEM and classified according to adhesive or cohesive failure mode. One specimen of each group was cut longitudinally, polished and prepared for SEM observation.

RESULTS

The TBS values were: Group 1 (7.86MPa+/-2.28), Group 2 (7.62MPa+/-1.85), Group 3 (7.60MPa+/-2.14), Group 4 (7.96MPa+/-2.36), Group 5 (7.50MPa+/-2.70) and Group 6 (7.18MPa+/-2.40). No significant statistical differences were observed among the groups. However, the analyses of the failure mode presented a considerable variation.

SIGNIFICANCE

The use of a filled adhesive or an unfilled adhesive along with a low-viscosity composite as an intermediate layer may provide a stress absorbing layer, whereby improving the preservation of the bonded interface area.

Bilateral talon cusp: case report

Talon cusp is an uncommon condition often present in the maxillary incisors and mandibular premolars. Morphologically, this anomaly has a well-delineated cusp that extends at least half the distance from the cementoenamel junction or cingulum area to the incisal edge. The alteration can cause clinical problems such as caries or occlusal interference. Management of the talon cusp varies according to the circumstances of the individual case and should be as conservative as possible. Presented is a case of bilateral bifid talon cusp in maxillary central incisors that was successfully managed with conservative therapy.