[Acute megakaryoblastic leukemia with leukemia cutis, meningeal leukemia, and myelofibrosis]

A 64-year-old man was admitted to our hospital with leukopenia. On admission, leukocyte count in the peripheral blood was 1,600/microliters, containing 24.5% blasts of lymphoid appearance, which were negative for myeloperoxidase. A bone marrow aspiration showed hypoplasia with increased blasts (31.6%). The blasts were ultrastructurally positive for platelet peroxidase (PPO) and positive for platelet membrane glycoprotein IIb/IIIa complex. A diagnosis of acute megakaryoblastic leukemia was made. Chemotherapy with behenoyl-ara C (BH-AC) (150 mg/day) was transiently effective. However, after three months, numerous nodules without itching appeared over the entire body, particularly on the anterior chest. A biopsy of the skin lesion revealed a diffuse fibrosis with infiltrations of the blasts. Bone marrow aspirations were dry tap, and a bone marrow biopsy showed marked myelofibrosis. Then, severe headache, vomiting, and loss of consciousness developed, and a lumbar puncture revealed infiltrations of blasts. Although methotrexate was intrathecally injected, he died due to the respiratory failure. As far as we know, a case of acute megakaryoblastic leukemia with leukemia cutis and meningeal leukemia is quite rare. In addition, it is interesting that megakaryoblastic leukemia was accompanied with both the fibrosis of skin and the myelofibrosis.