The causes of CML are not fully understood, and there is no evidence that CML can be prevented. However, in Australia, early detection is common because a full blood count is often ordered routinely or patients present to their general practitioner with tiredness, weight loss, malaise or symptoms related to an enlarged spleen.

The risk factors for developing CML include:

• gender – males are at a slightly higher risk of developing CML
• radiation exposure – exposure to high-dose radiation (e.g. nuclear disaster) can increase the risk of CML, but this is rarely relevant in Australia.

While there is no evidence linking lifestyle changes to reduced risk of CML, it is important to encourage people to reduce modifiable risk factors for other types of cancer and health conditions. This includes providing advice on preventing or reducing obesity and support to quit smoking.

General practitioners should be aware of the possibility of CML in patients with leucocytosis, or those with non-specific symptoms of fatigue, weight loss, sweats and malaise. Early satiety and abdominal discomfort may be related to progressive splenomegaly. Most cases of mild leucocytosis with neutrophilia will be due to other causes, but a PCR test for BCR-ABL1 to screen for CML should be ordered if the white cell count is over 25, leucocytosis or thrombocytosis is confirmed on a repeat blood test, or there are features on the blood film that raise the possibility of CML.