title: A case of a Ki-1 large cell anaplastic lymphoma with ultrastructural features.
abstract: A 29-year-old woman first presented in 1982 with a large cell lymphoma, initially thought to be of histiocytic origin on the basis of prominent sinus infiltration. She had a complete response to chemotherapy, but relapsed in 1987. Histologically, a repeat biopsy was identical to the first. Immunocytochemically, there was strong reactivity with Ki-1 antibody and histiocyte lineage markers, but all specific T cell markers were negative. Southern blot hybridization demonstrated a clonally rearranged band with the T cell receptor (T beta) probe. Ultrastructurally, the cells showed sparse organelles except for prominent paranuclear Golgi apparatus, frequent reniform nuclear indentations, and ruffled cytoplasmic membranes. This case appears to represent a Ki-1-positive lymphoma with the hybrid features of an activated T lymphocyte and a histiocyte.
authors.affiliation: Department of Pathology, University of Ottawa, Ontario, Canada.
authors.forename: B F
authors.initials: BF
authors.lastname: Burns
authors.forename: C
authors.initials: C
authors.lastname: Cripps
authors.forename: I
authors.initials: I
authors.lastname: Dardick
mesh_terms: D000328:Adult; D000943:Antigens, Differentiation / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D001706:Biopsy; D005260:Female; D006801:Humans; D007120:Immunochemistry; D017730:Ki-1 Antigen; D008223:Lymphoma / Q000276:immunology* / Q000473:pathology / Q000648:ultrastructure; D008854:Microscopy, Electron
chemical_list: D000943:Antigens, Differentiation; D000951:Antigens, Neoplasm; D017730:Ki-1 Antigen