RESUMO
The myoepithelium in human parotid, unlike that in other species, is not limited to the acinar-intercalated ductal system but extends to the intra- and extralobular striated ducts. Myoepithelial cells of the striated ducts are smaller, fewer, and different in shape but they are similar in their relationships and ultrastructural morphology to the acinar-intercalated system. Distribution of myoepithelium is discussed with respect to its role and participation in the histogenesis of salivary gland tumours, especially those of intermediate and large duct cell origin.
Assuntos
Glândula Parótida/ultraestrutura , Adenoma Pleomorfo/ultraestrutura , Adulto , Idoso , Epitélio/ultraestrutura , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Neoplasias Parotídeas/ultraestrutura , Neoplasias das Glândulas Salivares/ultraestruturaRESUMO
This ultrastructural study, based on 12 cases of adenoid cystic carcinoma of the major and minor salivary glands, was conducted to determine the role and extent of participation of myoepithelial cells in their histogenesis. The tumors were composed of four major cell types; intercalated duct, myoepithelial, secretory, and pluripotential reserve/stem cells. The cellular composition of adenoid cystic carcinoma is similar to that in the "terminal tubule" complex stage of a developing salivary gland except that in the tumor the pluripotential reserve/stem cells differentiate predominantly along the intercalated duct cell line rather than secretory cells as in the acinic cell carcinoma. Furthermore, adenoid cystic carcinoma appears to contain a far greater number of myoepithelial cells than acinic cell carcinomas.
Assuntos
Carcinoma Adenoide Cístico/patologia , Neoplasias das Glândulas Salivares/patologia , Adulto , Idoso , Membrana Basal/ultraestrutura , Carcinoma Adenoide Cístico/ultraestrutura , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Desmossomos/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias das Glândulas Salivares/ultraestruturaRESUMO
In a 66-year-old woman, a large solitary neurofibroma arising in the right infraorbital nerve extended into the maxillary antrum and the orbit. Following extirpation of this rare tumor, bony defects of the right orbital floor and inferior orbital rim were repaired with a biplanar supramid implant.
Assuntos
Neurofibroma/cirurgia , Neoplasias Orbitárias/cirurgia , Idoso , Diagnóstico Diferencial , Humanos , Masculino , Neurofibroma/diagnóstico por imagem , Neurofibroma/patologia , Órbita/patologia , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias Orbitárias/patologia , Tomografia Computadorizada por Raios XAssuntos
Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares Menores/patologia , Glândulas Salivares/patologia , Adenoma/patologia , Adenoma Pleomorfo/patologia , Adolescente , Adulto , Idoso , Carcinoma/patologia , Carcinoma Adenoide Cístico/patologia , Criança , Cistadenoma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Adenoid cystic carcinoma of the paranasal sinuses was demonstrated in a patient who subsequently developed a metastatic lesion to both orbits resulting in total blindness. While there are reports of extension of adenoid cystic carcinoma of the lacrimal gland to the adjacent orbit, this patient is an example of orbital extension of an adenoid cystic carcinoma of minor salivary gland originating in a paranasal sinus. The frequency and classification of this tumor also is reviewed.
Assuntos
Cegueira/etiologia , Carcinoma Adenoide Cístico , Neoplasias Orbitárias , Neoplasias dos Seios Paranasais , Sela Túrcica , Neoplasias Cranianas , Humanos , Masculino , Pessoa de Meia-Idade , Metástase NeoplásicaRESUMO
A microscopic histopathological study was done on 500 full-eyelid-thickness surgical specimens: 25 with the diagnosis of senile ectropion and 25 with that of senile entropion. Five different staining techniques were used. There appears to be significantly more orbicularis and Riolan's muscle ischemia, atrophy, and collagen fragmentation with ectropion than with entropion. Entropion shows more septal and tarsal atrophy. In both conditions, the skin and conjunctiva show chronic inflammation and scarring as a constant feature. Statistical significance at the 1% level was present for all six characteristics studied. These histopathological changes, if not etiological, are at least concomitant features differentiating senile ectropion from entropion at the microscopic tissue level.
