Explain why it would not be possible to accurately measure hemoglobin

Explain why it would not be possible to accurately measure hemoglobin concentration if the RBCs were not first lysed.Leukemia is a type of bone marrow cancer in which the hematopoietic tissue produces a very large number of immature leukocytes. At the same time, the patient is anemic and bruises easily. What does the anemia and easy bruising indicate about the effect of leukemia on red bone marrow?