Clinicopathologic and immunohistochemical characterization of 14 cases of angioleiomyomas in oral cavity

BACKGROUND: Angioleiomyoma (ALM) is a benign neoplasm that originates from vascular smooth muscle. It is extremely rare in oral cavity. The objective of this study was to evaluate the clinicopathological and immunohistochemical characteristics of all oral angioleiomyomas registered in a Center of Diagnosis of Oral Diseases from 1959 to 2017. MATERIAL AND METHODS: Slides from 14 cases of ALM stained with hematoxylin and eosin (H&E) were analyzed to confirm the diagnosis. Moreover, an immunohistochemical panel with alpha-smooth muscle actin (alpha-SMA), desmin, AE1/AE3, CD68, S-100, and CD34 antibodies was performed to evaluate semi-quantitatively the positive cells. RESULTS: ALM correspond to 0.08% of all benign oral tumors analyzed during the 57-year period. The mean age of the patients was 45 years with a predilection to males (58%). The most frequently reported site was lips (50%). Microscopic analysis on H&E sections revealed similar pattern in all cases, showing well-circumscribed and encapsulated tumors, characterized by a proliferation of smooth muscle cells and wide vascular spaces of varying sizes. The predominant immuno profiles were: alpha-smooth muscle actin (alpha-SMA) positive (strong immunoreactivity); positive variable pattern for desmin, negative immunoprofile for AE1/AE3, CD68, and S-100. The endothelial cells of vascular spaces were CD34+. CONCLUSIONS: Based on the results, the alpha-SM actin can be elected as a good marker for angioleiomyomas and can help the confirmation of the morphologic diagnosis of this lesion

Ameloblastic neoplasia spectrum: a cross-sectional study of MMPS expression and proliferative activity.

OBJECTIVE: To compare the proliferation and the expression of matrix metalloproteinases (MMPs; MMP-2 and MMP-9) in solid and unicystic ameloblastomas with ameloblastic carcinomas. STUDY DESIGN: Five cases of ameloblastic carcinoma (AC), 18 cases of solid ameloblastoma (SA), and seven of unicystic ameloblastoma (UA) were selected. The immunohistochemical expression of MMPs was assessed by the percentage of positive tumor cells and stained stroma. The mean argyrophilic nucleolar organizer region (AgNOR) and the percentage of cells with more than one AgNOR per nucleus were evaluated. RESULTS: Statistically significant higher mean AgNOR was observed in AC than in SA and UA. MMP-2 was expressed similarly in tumor and stroma among groups. MMP-9 was higher in the stroma of SA than that of UA (P = .0484). CONCLUSIONS: The cell proliferation was related to the greater aggressiveness of AC. High expression of MMP-2 and MMP-9 in all lesions highlighted the importance of these enzymes in the biology of ameloblastic tumors.

Differential diagnosis between oral fibroma and inflammatory hyperplasia: a proposal for histopathological criteria / Diagnóstico diferencial entre fibroma oral e hiperplasia fibrosa inflamatória: uma proposta para critério histopatológico

Aim: The present study proposed histopathological criteria for thedifferential diagnosis between those pathological entities. Materialsand methods: Histological sections of lesions histopathologicallydiagnosed as Oral Fibroma (n=61) and Inflammatory Hyperplasia(n=75) and were submitted to different techniques (HematoxylinEosin;Masson Trichrome and Phosphomolybdic acid - Picrosirius red)to allow quantitative and qualitative analysis. The qualitative analysisof collagen density was based on sections stained by HematoxylinEosinand focused in the center and periphery of each lesion.Results: Wound and collagen fibers were more frequent and higher inOral Fibroma, while parallel fibers were more frequent in InflammatoryHyperplasia (Fisher’s exact test, p<0.05). The percentage of parallelcollagen fibers beneath the epithelium was 72.22% and 92.3% in OralFibroma and Inflammatory Hyperplasia, respectively (Mann Whitney Utest, p<0.05). The parallel collagen fibers in the center of the lesionwas found in 84.6% of Inflammatory Hyperplasia cases and wasabsent in 88.88% of Oral Fibroma. The central portion of Oral Fibromahad characteristically a dense and wound arrangement of collagenfibers. Conclusion: Oral Fibroma and Inflammatory Hyperplasia havedistinctive features that may be useful in routine histopathologicalanalysis, supporting the differential diagnosis.

Objetivos: O presente estudo propôs critérios histopatológicos para odiagnóstico diferencial entre as entidades patológicas. Materiais emétodos: Cortes histológicos de lesões diagnosticadasmicroscopicamente como Fibroma Oral (n=61) e Hiperplasia FibrosaInflamatória (n=75) foram submetidos a diferentes técnicas decoloração (Hematoxilina-eosina, Tricrômio de Masson e ÁcidoFosfomolibidico- Vermelho de Picrosírius) para permitir análisesquantitativa e qualitativa. A análise qualitativa da densidade docolágeno foi baseada nas lâminas coradas em Hematoxilina- eosinae observada no centro e periferia de cada lesão. Resultados: Fibrascolágenas enoveladas eram mais frequentes e mais densas noFibroma Oral, enquanto as fibras paralelas e ram observadas naHiperplasia Fibrosa Inflamatória (teste exato de Fisher, p<0,05). Nocentro da lesão, fibras colágenas paralelas foram encontradas em84,6% dos casos de Hiperplasias Fibrosas Inflamatórias e ausentesem 88,88% dos Fibromas Orais. A porção central do Fibroma Oral eracaracterizado por um arranjo denso e frouxo das fibras colágenas.Conclusão: o Fibroma Oral e a Hiperplasia Fibrosa Inflamatóriapossuem características bem distintas que pode ser útil na rotina daanálise histopatológica, auxiliando no diagnóstico diferencial.