Chronic myelogenous leukemia laboratory tests

Overview
Patients are often asymptomatic at diagnosis, presenting incidentally with an elevated white blood cell count on a routine laboratory test. In this setting, CML must be distinguished from a leukemoid reaction, which can have a similar appearance on a blood smear.

Laboratory tests
CML is often suspected on the basis on the complete blood count, which shows increased granulocytes of all types, typically including immature myeloid cells. Basophils and eosinophils are almost universally increased; this feature may help differentiate CML from a leukemoid reaction.