title: Extramedullary megakaryoblastic tumors following an indolent phase of myelofibrosis.
abstract: A 59-year-old man developed multiple subcutaneous and bone tumors after 2 years' duration of indolent myelofibrosis. These tumors exhibited a diffuse proliferation of pleomorphic blast cells. The skeletal x-rays showed disseminated osteolysis and osteosclerosis. Blast cells obtained from the pleural effusion did not react with myeloperoxidase, sudan black B or non-specific esterase. Genotypic analysis of DNA samples at autopsy did not demonstrate rearrangements of T-cell receptor beta-chain or immunoglobulin heavy-chain genes. Frozen-section immunohistochemical studies revealed that the neoplastic cells were derived from megakaryocytic lineage. The present case represents a novel and unusual subtype of megakaryocytic neoplasm.
authors.affiliation: Third Department of Internal Medicine, Akita University School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Chubachi
authors.forename: H
authors.initials: H
authors.lastname: Wakui
authors.forename: I
authors.initials: I
authors.lastname: Miura
authors.forename: M
authors.initials: M
authors.lastname: Saitoh
authors.forename: T
authors.initials: T
authors.lastname: Nishinari
authors.forename: S
authors.initials: S
authors.lastname: Nishimura
authors.forename: A B
authors.initials: AB
authors.lastname: Miura
mesh_terms: D001859:Bone Neoplasms / Q000209:etiology* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007947:Leukemia, Megakaryoblastic, Acute / Q000209:etiology* / Q000473:pathology; D008297:Male; D008533:Megakaryocytes / Q000473:pathology*; D008875:Middle Aged; D055728:Primary Myelofibrosis / Q000150:complications*