• APML is treated differently to other types of AML.

What causes acute promyelocytic leukaemia?

A switching of chromosomes occurs between genes that would normally help white blood cells to mature in a healthy way. When these genes trade places, a mutant gene is formed, which makes it difficult for normal genes to do their job.

What are the symptoms?

Signs and symptoms of acute promyelocytic leukemia are similar to other forms of AML.

They include:

• Fatigue

• Minor infections

• A tendency to bleed

• Anaemia

• Low levels of platelets (needed for blood to clot normally)

• Unusual bleeding

How is it diagnosed?

Usually, a GP will examine the patient and take a blood test. If the results of the test are abnormal, they’ll make a referral to hospital for advice from a doctor who specialises in the treatment of blood problems (a haematologist).

The haematologist will:

• Ask questions about the patients health and about any previous illnesses they've had.

• Examine the patient to find out how they are physically and take a blood sample to check the numbers of different types of blood cells in their blood (called a ‘full blood count’).

If the blood test shows that leukaemia cells are present, the doctor will want to take a sample of bone marrow.

How is it treated?

APML is unique from other leukaemias in the fact that it responds well to trans-retinoic acid (vitamin A) therapy.

This treatment helps make the leukaemic cells either mature properly or die, and can induce remission in a great majority of patients.

It is often used in conjunction with chemotherapy.