The cells in your blood (red blood cells, platelets and white blood cells) are all formed from stem cells in bone marrow – the soft tissue inside your bones. These stem cells are called myeloid stem cells or lymphoid stem cells.
Leukaemia happens when these stem cells grow abnormally and in an uncontrolled way and produce too many white blood cells. It’s thought to start from just one abnormal cell. Large numbers of abnormal cells in your bone marrow makes it difficult for normal, healthy cells to develop. Abnormal cells also spill into your blood stream.
There are different types of leukaemia depending on the cell they affect (eg myeloid or lymphoid) and whether they’re chronic (progressing slowly over many years) or acute (progressing quickly and aggressively).
The main types of leukaemia are:
The type of treatment, as well as the outcome, depends on the type of leukaemia you have.
Symptoms are generally caused by a lack of normal blood cells, rather than by too many abnormal cells. Problems include:
Other symptoms include:
Your doctor will discuss your symptoms and recommend a full blood count (FBC) to detect abnormal cells. If this suggests leukaemia, you’ll usually have a bone marrow sample taken for further analysis to confirm the diagnosis.
You may be referred to a consultant to assess if the leukaemia has spread.
Most cases of leukaemia have no obvious cause but factors that increase your risk of getting it include:
The treatment advised will depend on the type of leukaemia you have and how far it has progressed.
Acute myeloid leukaemia
Treatment for AML should begin as soon as possible because it’s an aggressive cancer that develops quickly. This usually starts with an intensive round of chemotherapy with regular blood transfusions to provide you with healthy blood cells. Later, less intensive chemotherapy is recommended to help prevent cancer cells from returning.
Chronic myeloid leukaemia
Because CML is slow growing, it’s possible to control it with medications. Chemotherapy is often used if it progresses. Some people can even be cured with a stem cell or bone marrow transplant, however, this is more common in younger people.
Acute lymphoblastic leukaemia
ALL is usually treated as soon as possible because it can develop rapidly. The main treatment is intensive chemotherapy (and sometimes radiotherapy) to kill the abnormal cells. Other treatments include antibiotics, blood transfusion and in some cases a bone marrow transplant.
Chronic lymphocytic leukaemia
If CLL is diagnosed in the early stages, you may not need treatment but will require regular check-ups. If it starts to cause symptoms, chemotherapy is the main treatment to control it. Stem cell or bone marrow transplants are occasionally used to cure it completely, but as with CML, this is not suitable for everyone.