title: Phenotypic and ultrastructural characterization of a medullary thymocyte acute lymphoblastic leukemia with cellular procoagulant activity.
abstract: The phenotypic and ultrastructural characterization of the blast cells from a T-cell acute lymphoblastic leukemia (T-ALL) that was associated with disseminated intravascular coagulation (DIC) is described. The bone marrow blasts were considered to represent neoplastic medullary thymocytes and were acid phosphatase (+), terminal deoxynucleotidyl transferase (-), acid alpha-naphthyl acetate esterase (-), E-rosette (+) at 4 degrees C and 37 degrees C, Fc- and C3-receptor (-), and cALLA-, Ia-, 9.6+, OKT3+, OKT4+, OKT6+/-, OKT8+, OKT10+. On transmission electron microscopic study, the predominant cell was 6 micron in diameter and possessed an irregular nucleus, moderate-sized nucleolus, marginated heterochromatin, abundant Golgi elements and granules, and prominent intermediate filaments. The cells were analyzed with normal and factor-deficient human plasmas and contained significant amounts of tissue factor-like procoagulant activity. This is the first report of a well-characterized medullary thymocyte T-ALL in which DIC was an accompanying feature, and the first demonstration of tissue factor-like procoagulant activity in acute lymphoblastic leukemia. In view of thrombohemorrhagic phenomena observed in association with other medullary thymocyte leukemias, these findings suggest that tissue factor-like procoagulant activity may be a characteristic of medullary thymocyte-derived lymphoid leukemias.
mesh_terms: D000208:Acute Disease; D000328:Adult; D000911:Antibodies, Monoclonal; D001779:Blood Coagulation Factors / Q000032:analysis; D001853:Bone Marrow / Q000648:ultrastructure; D002462:Cell Membrane / Q000276:immunology; D003546:Cysteine Endopeptidases; D004211:Disseminated Intravascular Coagulation / Q000150:complications*; D010450:Endopeptidases / Q000032:analysis; D006801:Humans; D007945:Leukemia, Lymphoid / Q000150:complications* / Q000276:immunology; D008297:Male; D008479:Mediastinal Neoplasms / Q000150:complications; D008854:Microscopy, Electron; D009000:Monocytes / Q000145:classification / Q000648:ultrastructure; D009363:Neoplasm Proteins; D010641:Phenotype; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000145:classification* / Q000648:ultrastructure
chemical_list: D000911:Antibodies, Monoclonal; D001779:Blood Coagulation Factors; D009363:Neoplasm Proteins; D011947:Receptors, Antigen, B-Cell; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; C030910:cancer procoagulant