Anemia and extramedullary hematopoiesis associated with carcinoma of the breast

Three patients with carcinoma of the breast, extensive metastasis, and splenomegaly are described. Radioisotope studies with 59Fe and 51Cr revealed extramedullarly hematopoiesis and hemolysis. In addition to red cell hemolysis, ineffective erythropoiesis in the marrow and extramedullary sites contributed to the persistence of the anemic syndrome. Extramedullary hematopoiesis is not an effective compensatory mechanism in some patients with anemia and carcinoma of the breast.