Find out about the different types of acute myeloid leukaemia (AML).
Acute myeloid leukaemia is divided into different groups (sub-types).
There are 2 systems: the FAB and WHO systems. Ask your doctor which system they are using if you are unsure.
Your team plans your treatment according to the particular type of acute myeloid leukaemia you have.
Finding the type of AML
Your doctor looks at your leukaemia cells under a microscope to find out which group your leukaemia is in.
Your doctor also does tests for:
- proteins that some types of leukaemia cells make - called immunophenotyping tests
- chromosome changes in the leukaemia cells - cytogenetic testing
The FAB system
The FAB system stands for the French-American-British system. Your FAB type depends on:
- how your leukaemia cells look under the microscope
- antibody proteins on the leukaemia cells
There are 8 types of AML in the FAB system. They all have numbers and names:
M0, M1 and M2
Together these are types of myeloblastic leukaemia. They make up just under half of all cases.
This is called acute promyelocytic leukaemia (APL). This makes up 1 in 10 cases of AML (10%).
M4 and M4eos
These are both types of acute myelomonocytic leukaemia. Together they make up 1 in 4 cases (25%).
This is called acute monocytic leukaemia. It makes up 1 in 10 cases (10%).
This is acute erythroleukaemia. It's very rare.
This is acute megakaryoblastic leukaemia. It's very rare.
World Health Organisation (WHO) typesThe World Health Organisation (WHO) classification system divides AML into groups according to the type of myeloid cell that has become abnormal. It also looks at whether:
- there are chromosomal (genetic) changes in the cells
- your leukaemia developed from a blood disorder
- more than one type of blood cell has abnormal changes
- your AML developed after other treatment for cancer
In acute myeloid leukaemia, a lump of cells can collect outside the bone marrow. This is called a granulocyctic sarcoma.
You can get these anywhere in the body.
Treatment depends on the type of granulocytic sarcoma and where the lump of cells is. Ask your doctor about your treatment plan.
Panmyelosis is usually referred to as acute panmyelosis with myelofibrosis (APMF) or acute myelofibrosis.
Myelofibrosis means there's scar tissue inside the bone marrow instead of normal tissue. This causes panmyelosis, which means that the bone marrow can't produce enough red blood cells, white blood cells or platelets. It's a very rare form of AML.
Mixture of AML/ALL
Some leukaemias seem to be a mixture of AML and acute lymphoblastic leukaemia (ALL). The abnormal cells have particular proteins called markers for both ALL and AML.
Doctors call these acute biphenotypic leukaemias. Biphenotypic (bye-fee-no-tip-ik) means both types and is extremely rare.
Your treatment will depend on:
- what your leukaemia cells look like down the microscope
- your general health
- your age
Your doctor will let you know your treatment plan.