- This measures the number of red cells, the different types of white cells, and platelets in the blood. The blood is also smeared onto a microscope slide, allowing the blood cells to be examined under the microscope.
- Leukaemia cells have limited cytoplasm sometimes with a single long projection (See labelled cell in Figure 2). The nucleus is indistinct with no nucleoli (Figure 6).
- Levels of red blood cells, neutrophils and platelets are typically reduced as the bone marrow is busy making leukaemia cells.
- There are typically more white blood cells than normal. The total level of white blood cells is increased because of the marked increase in the numbers of leukaemia cells. However, the leukaemia cells are defective.
Figure 6 Lymphocyte leukaemia cells
 Normal lymphocyte |
 Abnormal leukaemia lymphocytes |
