Clinical studies on iron metabolism of erythroblasts in preleukemic stage

The appearance of sideroblasts in hypoplastic anemia (HAl and acute myelocytic leukemia (AML), together with their sideroblastograms, was studied. Hematological studies on cases with type III sideroblast dominance by sideroblastograms produced the following results. Type III sideroblast dominant HA was observed in three of 63 cases. Two of the above three cases had what we call "atypical factor", while the remaining one became AML in its clinical course and could be considered to be leukemia in a hypoplastic preleukemic stage. Type III sideroblast dominant AML was noted in five of 32 cases. Three of these five cases are compatible with low percentage leukemia, and one of the above three cases showed ringed sideroblasts exhibiting erythroleukemia in the terminal stage. In HA and AML, type III sideroblast dominant cases have to be examined in relation to atypical HA and atypical leukemia. Changes of iron meta. bolism in erythroblasts with preleukemic stage will be attributable to disturbance of erythropoiesis such as erythroid hyperplasia in bone marrow and also, in part, to disturbance of hemoglobin synthesis.