title: Ultrastructural observations on smooth muscle tumors.
abstract: The ultrastructure of a series of primary and metastatic smooth muscle tumors is reviewed. Myofilaments and other smooth muscle features were present in all primary leiomyosarcomas of the soft tissues and uterus. They were also present but were less plentiful in most of the metastatic leiomyosarcomas. Electron microscopy is therefore a useful method to establish the diagnosis of a suspected leiomyosarcoma. Stromal tumors of the gastro-intestinal tract may require correlated immunocytochemical and ultrastructural studies for their identification: 9 of the 50 cases examined were positive with immunostaining for S-100 protein, and 16 tumors with epithelioid transformation did not show evidence of smooth muscle differentiation by electron microscopy.
authors.affiliation: Department of Pathology, University of Texas M.D. Anderson Hospital and Tumor Institute, Houston 77030.
authors.forename: B
authors.initials: B
authors.lastname: Mackay
authors.forename: J
authors.initials: J
authors.lastname: Ro
authors.forename: C
authors.initials: C
authors.lastname: Floyd
authors.forename: N G
authors.initials: NG
authors.lastname: Ordóñez
mesh_terms: D008841:Actin Cytoskeleton / Q000648:ultrastructure; D005260:Female; D005354:Fibrosarcoma / Q000648:ultrastructure; D005770:Gastrointestinal Neoplasms / Q000648:ultrastructure*; D005918:Glomus Tumor / Q000648:ultrastructure; D006393:Hemangiopericytoma / Q000648:ultrastructure; D018219:Histiocytoma, Benign Fibrous / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D007890:Leiomyosarcoma / Q000648:ultrastructure*; D008854:Microscopy, Electron; D009130:Muscle, Smooth; D009208:Myoepithelioma / Q000648:ultrastructure; D012983:Soft Tissue Neoplasms / Q000648:ultrastructure*; D014594:Uterine Neoplasms / Q000648:ultrastructure*