September marks Bone Marrow Donor Awareness Month

A cancer of blood-forming organs, leukaemia is affecting a growing number of people around the world, including here in South Africa. International studies show that the incidence of leukaemia is currently about 16.1 per 100 000 men and 9.7 per 100 000 women, and that these rates are increasing every year¹.

According to Professor Vernon Louw, Head of the Clinical Haematology Unit in the Department of Internal Medicine at the University of the Free State, leukaemia already accounts for around 2% of South African cancer cases and the 'lifetime risk' of developing leukaemia (the probability of suffering the disease sometime during our lives) is 1 in 77 or 1.3%.

"My colleagues and I have far more patients than we can handle," confirms Professor Louw. "All of our units are flooded nationwide. The increase in numbers of patients in recent years has been staggering. Ideally, treatment should be started within 48 hours, but we now have growing waiting lists and patients are struggling to get into the wards."

What is leukaemia?

Leukaemia is typically characterised by the over-production of white blood cells (leukocytes). "Most leukaemias cause an increase in white cell production," verifies Professor Louw, "and these eventually push out other healthy cells in the bone marrow, affecting the body's ability to produce the range of blood cells necessary for normal functioning."

Are all leukaemias the same?

Many people mistakenly believe that 'all leukaemia is the same', but there are actually many different types. "There are at least a dozen," observes Professor Louw, "each one responding to completely different treatments and with very different success rates."

The different leukaemias can be broadly defined and grouped as either 'acute' or 'chronic'. Acute leukaemias develop rapidly and, without treatment, patients can die within a matter of days or weeks. Conversely, in chronic leukaemias, the cancerous cells take longer to become fully functional and the disease develops over months or years.

Are all leukaemias fatal?

Another common misconception is that all leukaemias are fatal. "When the news came back that I had CML (Chronic Myelogenous Leukaemia), all I heard was 'leukaemia' and all I could think about was losing my hair and dying. It was a very scary time," recalls Roxine van der Merwe.

It's a misunderstanding that Professor Louw encounters fairly regularly and another reason why he is committed to raising awareness of the disease. "Some leukaemias are still fatal," he acknowledges, "but contemporary treatments, especially targeted therapies and transplantation, have dramatically improved patient survival rates. In the case of CML, for example, 85% of patients now survive more than eight years on treatment."

This is certainly true in Roxine's case. It has been five years since she was diagnosed with CML and the 28 year old is now in complete remission (her white blood cell count is normal).

New therapies have changed everything

"Targeted therapies, which focus on the cancer cells at a molecular level, have changed everything," enthuses Professor Louw. "These breakthrough drugs can kill off cancerous cells in a matter of months, compared to the years taken by traditional chemotherapy. The average time for a newly diagnosed patient to get to the 'safe haven' of complete cytogenetic haematological remission is now between two - three months."

Not only do these new therapies work much faster than traditional chemotherapy, their side effects are far less severe. Instead of indiscriminately destroying all rapidly dividing cells, good and bad, they mainly disrupt the functioning of cancerous cells. "In fact, one of the challenges is that patients tend to feel so much better that they stop taking the therapy as they think that they are cured which leads to resistance developing ," observes Professor Louw.

Second generation targeted therapies have been developed that are even swifter and more precise in attacking cancer cells. "Two second generation TKIs (Tyrosine-Kinase Inhibitors) have been tested in Phase III clinical trials," reports Professor Louw, "and they are proving to be much more accurate and powerful than the original breakthrough therapy for CML in chronic phase."

Real hope now

Professor Louw argues that these exciting advances and the huge progress being made against almost all leukaemia outcomes show that there is real hope now for most patients. "Patients are naturally going to be afraid and confused when they are first diagnosed," he recognises, "but the first thing they should do is arm themselves with as much knowledge about the disease as possible. This will help dispel many of their fears and help them to make informed choices regarding their treatment options."

What causes leukaemia?

The causes of leukaemia are not completely understood. It doesn't appear to be hereditary, although genetic abnormalities can cause some types of leukaemias. Researchers have, nonetheless, found certain risk factors that increase a person's risk of getting leukaemia, for example, exposure to large amounts of radiation and certain chemicals, such as benzene, over a long period of time. There is also a possible link between smoking and the disease.

Signs and symptoms

Symptoms to watch out for include: fatigue, weight loss, fever, swollen glands, as well as persistent, unexplained bone and joint pain or abdominal swelling. Spontaneous bleeding is also another sign. It's important to note, though, that many other benign conditions may also present with similar symptoms. See your doctor if you are in any way concerned or if any of these symptoms persist.

Source:

[1] US National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) Program SEER Stat Fact Sheets: Leukaemia. Last accessed: 26-08-2011