RESUMO
The aim of this study was to analyze the clinico-pathological and immunohistochemical features of 62 cases of odontogenic myxoma (OM) diagnosed in three Oral Pathology Diagnostic Services in Latin America, as well as to describe the ultrastructural features of three of these cases. OM showed a wide age range (9-71 years), with a mean of 27.97 yr (SD: 11.01) and a male to female ratio of 1:2.2. Mandible was affected in 37 cases (59.6%) and maxilla in 25 (40.4%), with 61.3% located in the posterior region. Thirty-nine cases (62.9%) were multilocular and 23 (37.1%) unilocular. Size ranged from 1 to 13 cm, (mean: 5.2 cm). Thirty-seven multilocular (54.8%) and 6 unilocular lesions (26%) were larger than 4 cm (p<0.05). Epithelial islands were identified in 5 cases (8%) on H&E stained sections, but AE1/AE3 and CK14 disclosed these structures in 15 cases each (24.2%); CK5 was positive in 8 (12.9%); CK7 in 2 (3.2%) and CK19 in only 3 cases (4.8%). All cases were negative for CKs 8 and 18, S-100 protein, NSE and CD68, and showed a low index of expression of Bcl2 and ki-67 proteins (<1%). Mast cell antibodies showed these cells in 45 cases (72.6%). Myofibroblastic differentiation evidenced by myofilaments and fibronexi was found in one case out of the three studied by TEM and 29 cases (46.7%) were positive by immunohistochemistry for alpha actin. In conclusion, only a minority of OM had epithelial islands, and only 3 cases expressed CK 19, indicating an odontogenic epithelium origin. Immunohistochemical and ultrastructural findings suggest that OM is a mesenchymal neoplasm in which several factors may contribute to its pathogenesis, including myofibroblastic differentiation and the participation of mast cell products. However, further investigations are needed to better understand the participation of these elements in this particular neoplasm.
Assuntos
Neoplasias Mandibulares , Neoplasias Maxilares , Tumores Odontogênicos , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Criança , Feminino , Humanos , Imuno-Histoquímica , Masculino , Neoplasias Mandibulares/metabolismo , Neoplasias Mandibulares/patologia , Neoplasias Mandibulares/ultraestrutura , Neoplasias Maxilares/metabolismo , Neoplasias Maxilares/patologia , Neoplasias Maxilares/ultraestrutura , Pessoa de Meia-Idade , Tumores Odontogênicos/metabolismo , Tumores Odontogênicos/patologia , Tumores Odontogênicos/ultraestrutura , Adulto JovemRESUMO
El ameloblastoma se origina de la lámina dentaria o de sus derivados, es un tumor localmente invasor, el más agresivo y frecuente de los tumores odontogénicos. Es de crecimiento lento que invade localmente, con una alta tendencia a la recidiva. Puede ser periférico o intraósea, que es el más frecuente. El periférico es menos agresivo e invasor y con una tendencia a la recidiva. Presenta un patrón histológico variado siendo los más comunes el folicular y el plexiforme. Las formas foliculares con más recidivantes que los plexiformes y las multioculares más que las uniloculares. Radiológicamente es una lesión radiolúcida, quística que se extiende de la región molar hasta la porción superior de la rama mandibular, con multilocularidad, variación en el tamaño de las loculaciones, expansión de la cortical, bordes bien definidos y resorción de las raíces dentales. Su incidencia alta de recidiva y lo complejo de las estructuras faciales que afectan hace que su abordaje terapeútico deba realizarse con base en un criterio médico multidisciplinario
Assuntos
Humanos , Feminino , Adulto , Radiografia , Ameloblastoma/cirurgia , Ameloblastoma/tratamento farmacológico , Ameloblastoma/radioterapia , Neoplasias Mandibulares/cirurgia , Neoplasias Mandibulares/patologia , Neoplasias Mandibulares/ultraestrutura , Diagnóstico DiferencialRESUMO
Central granular cell tumor of the jaw was formerly known as granular cell ameloblastic fibroma; recently, the term central granular cell odontogenic fibroma has been proposed. This study attempts to determine the ultrastructural features and selected immunohistochemical properties of the tumor cells. Four formalin-fixed specimens were processed for electron microscopy, and for immunohistochemical staining with antiactin, anti-glial fibrillary acidic protein, and OKT6 (CD1) with the avidin-biotin-peroxidase complex method. Tumor cells contained many primary lysosomes, autophagic vacuoles, and phagocytic vacuoles. The phagocytic vacuoles appeared to contain collagen fibrils. Tumor cells stained positive with antiactin and OKT6 (CD1), and negative with anti-glial fibrillary acidic protein. The results indicate that tumor cells are actively phagocytic and suggest that tumor cells might arise from Langerhans' cells.