Acute erythroid leukaemia. Light micrograph of blood cells from bone marrow in a case of acute erythroid leukaemia. The cells include dystrophic erythroblasts (nuclei stained dark red), a degenerated form of erythroblasts. Erythroblasts are the immediate precursors to mature red blood cells as they develop from stem cells in the bone marrow. Acute erythroid leukaemia is a rare form of acute myeloid leukaemia (a blood cell cancer) where the excess blood cell production is of erythroblasts. The pale orange cells are normal red blood cells.