top of page

Magnification 1000x microscope of abnormal cells or cancer cells in the blood. (Source: Shutterstock)

Chronic myeloid leukemia (CML)


Definition of chronic myeloid leukemia (CML)


Chronic myeloid leukemia (CML) is a degeneration and maturation disorder of haematopoietic stem cells.

Also known as chronic myelosis, it is a type of cancer that is associated with a proliferation of leukocytes (white blood cells), especially granulocytes and their precursors, in the blood and blood-forming bone marrow.


In contrast to acute myeloid leukaemia, all three cell rows multiply at all stages of maturation in the initial stage.

Symptoms of chronic myeloid leukemia (CML)


The disease is often asymptomatic in the initial phase.

The main symptoms in the chronically stable phase are fatigue, loss of energy and night sweats. There is an increase in leukocytes in the blood and an enlargement of the spleen, which can also cause a feeling of pressure in the left upper abdomen. There is also a knocking or pressure pain in the breastbone.

Later, leukocytosis is associated with a deficiency of red blood cells (anemia) and thrombocytopenia (a deficiency of blood platelets). In addition, tumour fever, bone pain and often weight loss are present. The spleen can enlarge further.

In a later stage of the disease, the bone marrow produces immature precursors of blood cells - so-called blasts - and releases them into the blood. The number of blasts rises to over 30 percent of all blood cells.

Diagnosis of chronic myeloid leukemia (CML)

A detailed blood test provides information about the pathological change in the distribution of the blood components. In addition, the Philadelphia chromosome can be detected in 90 percent of all patients, indicating the presence of CML.

Chronic myeloid leukemia mainly affects adults and occurs more frequently with increasing age. Patients are often diagnosed in the sixth decade of life; only about ten percent of patients are younger than 35 years of age at diagnosis. Men are affected about 1.4 times more frequently than women.

bottom of page