MYELOFIBROSIS, SPLENOMEGALY AND MEGAKARYOCYTIC MYELOSIS

Abstract

FROM time to time cases have been reported in the literature in which there were splenomegaly and an unusual white blood cell count, which do not fit into any recognized pathologic category. Such cases are reported as: "Chronic nonleukemic myelosis"¹; "myelofibrosis associated with a leukemoid blood picture"²; "osteosclerosis with extensive extramedullary hematopoiesis and a leukemoid blood picture"³; "marrow sclerosis associated with massive myeloid splenomegaly"⁴; "splenomegaly with myeloid transformation"⁵; "megakaryocytic myelosis with osteosclerosis,"⁶ and "aleukemic myelosis with osteosclerosis."⁷ The similarity between these cases and the one reported here is striking and suggests the possibility of a disease entity which is infrequent enough to elude early recognition. All of these cases in which there was splenomegaly have been characterized by megakaryocytes in the spleen, liver, lung, lymph nodes, peripheral blood and elsewhere with an accompanying disturbance in the number and type of circulating platelets. The circulating white blood cells, regardless of the total count, have shown myeloblastic