Does cancer show up in routine blood work?
Cancer does not show up in routine blood work, and that includes the complete blood count. However, your doctor may notice an abnormally high or abnormally low white blood cell count or red blood cell count, which is very important to make the diagnosis.
We can have a high or low count in cases of anemia, during transient infections, and other health problems. But the numbers obtained in leukemia are alarmingly low or high and often require confirmation tests. The type of white blood cells usually involved are eosinophils, basophils, and neutrophils, but routine blood work will not describe the characteristics of the cells, which is important for diagnosis and will be ordered in additional blood tests.