title: Peculiar ultrastructural features in the cytoplasm of cells from human effusions associated with malignant disease.
abstract: A peculiar structure revealed by the electron microscope in a few cells from two human pleural fluids, showing the morphologic features of metastasizing cancer cells in effusions, is described. It has the appearance of a rod-shaped pentalaminary structure approximately 25-35 nm thick formed by an outer double membrane, surrounding a central, more dense axis showing transverse striations at about 10-nm intervals. The double membrane often exhibits a terminal expansion connected with the endoplasmic reticulum and it is sometimes associated with microfilaments. These structures could be a variant of or represent a step in the formation of confronting cisternae, but the periodic striations they show in the more dense lamella give them some resemblance to a Langerhan's cell granule. To date, such striations have not been seen in confronting cisternae.
mesh_terms: D000230:Adenocarcinoma; D001943:Breast Neoplasms; D003110:Colonic Neoplasms; D003593:Cytoplasm / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D010996:Pleural Effusion; D010997:Pleural Neoplasms / Q000556:secondary / Q000648:ultrastructure*