ABSTRACT
Pituicytoma is a rare neoplasm occurring in the sellar and suprasellar regions. The tumor is currently considered to arise from the pituicyte, a specialized glial cell of the posterior lobe and the stalk of the pituitary gland. The authors describe a case of pituicytoma, focusing on the ultrastructural features. The patient was a 79-year-old woman with hypopituitarism and visual disturbances. Immunohistochemically, the tumor showed strong and diffuse positivity for vimentin, and EMA and GFAP were focally detectable. Ultrastructurally, the lesion was composed of elongated cells containing in the Golgi area aggregates of intermediate filaments in a concentric pathway (fibrous body), and secretory granules. These features intermediate between a pituicytoma and a pituitary adenoma suggest that "pituicytomas" may also arise from the specialized stromal folliculo-stellate cells of the adenohypophysis, which are able to differentiate into endocrine cells.
Subject(s)
Glioma/pathology , Neuroglia/pathology , Pituitary Gland, Posterior/pathology , Pituitary Neoplasms/pathology , Aged , Cell Lineage/physiology , Cell Nucleus/pathology , Cell Nucleus/ultrastructure , Female , Glial Fibrillary Acidic Protein/metabolism , Glioma/metabolism , Glioma/ultrastructure , Humans , Immunohistochemistry , Microscopy, Electron , Mucin-1/metabolism , Neuroglia/ultrastructure , Organelles/pathology , Organelles/ultrastructure , Pituitary Gland, Posterior/ultrastructure , Pituitary Neoplasms/metabolism , Pituitary Neoplasms/ultrastructure , Secretory Vesicles/ultrastructure , Vimentin/metabolismABSTRACT
The authors present a new, advanced system for electrocoagulation. In order to solve the problems connected with standard and bipolar EC machines available to date (i.e.: uneven and incostant coagulation; adhesion of tissue to the tips of the forceps, etc.), the Authors realized bipolar screened forceps with a well balanced current flow to avoid any heat dissipation. This new type of forceps are fed by a peculiar, two-step heating pattern, time dependent, that coagulates only the core of the clamped tissue.
