HITHERTO there have been only two diseases known in which he megakaryocytes occupy the center of the pathologic picture. One is thrombopenic purpura, in which these cells suffer an injury. The other is chronic aleukemic myelosis, characterized by an extramedullary megakaryopoiesis. A case of acute megakaryoblastic leukemia, the only one so far recorded in the literature, was described by von Boros.1 However, its authenticity is doubted by some hematologists.2 In other lesions in which these bone marrow cells are involved, such as in chronic myeloid leukemia, hyperthyroidism and polycythemia, they merely play a secondary role.
In the present case the megakaryocytes were the elements affected principally and in a manner unique in hematologic history. It is reported, also, because of the light it throws on the problems concerning the origin and maturation of megakaryocytes and the derivation of platelets from them.
REPORT OF A CASE
G. M., a