Hope for Chronic Myeloid Leukaemia patients

Chronic Myeloid Leukaemia, or CML, is one of the lesser known strains of Leukaemia, but one which is receiving increasing media attention due to the dramatic success rate of a relatively new treatment plan. Today, 85% of patients are surviving for at least eight years post diagnosis thanks to the advancement of modern medicine, says Professor Vernon Louw, a haematologist and head of the Department of Internal Medicine at the University of the Free State.

‘Leukaemia’ is an emotionally-charged word, typically associated with childhood and bringing with it the worst fears of every parent. But the reality is that there are several different types of leukaemia, many of which occur in adulthood, and each of which have an entirely different prognosis.

Chronic Myeloid Leukaemia, or CML, can be broken down into its three naming constituents: chronic, because it is slow growing; myeloid, because it affects the white blood cells; and leukaemia, because it is essentially a cancer of the blood or bone marrow.

Contrary to the public perception of leukaemia, CML occurs more frequently in adults, specifically in their 50s, 60s and 70s. Although childhood cases have been diagnosed, they are quite rare. [i]

There is no known environmental cause for CML, but specialists have detected a very specific gene mutation at its root, explains Dr David Brittain, a haematologist based in Pretoria.

“It is caused by a mutation in the marrow stem cells where a piece of chromosome 9 swaps with a piece of chromosome 22. This mutation is called the ‘Philadelphia Chromosome’ and actually moves a tyrosine kinase signaling gene to a growth gene causing the overgrowth of the white cells in the blood,” says Dr Brittain.

“This overgrowth in white blood cells results in a chronic inflammatory state with patients experiencing fatigue, weight loss and drenching night sweats. As the leukaemia progresses these symptoms get worse and the spleen enlarges, causing pressure on the stomach and a bloated feeling.

“If left untreated, CML progresses to an acute (or aggressive) leukaemia in about 30 months. This phase is a resistant leukaemia which is hard to treat,” cautions Dr Brittain.

Unfortunately, because the symptoms of CML are so vague, the disease is often only picked up as the result of a routine blood test which shows an over-abundance of white cells. Even then, this is not a sign that the patient has CML – he or she would need to undergo a more specific blood test and possibly also a bone marrow test. Finally, a genetic test confirming the presence of the Philadephia Chromosome will confirm the diagnosis.[ii]

Successful treatment of CML

But the good news is that, thanks to a new class of drugs know as tyrosine kinase inhibitors (or TKI’s), there is treatment for CML sufferers – and these TKI’s have changed CML (for most patients) from what was once a relatively fast-progressing fatal disease into a chronic manageable condition.

In essence, TKI’s function by blocking the protein that is coded for by the Philadelphia gene and thereby controlling the growth of the CML cells. Over the past ten years, TKIs have become standard treatment for CML. [iii]

Dr Brittain explains that the TKI’s are very potent drugs and can suppress the leukaemia to below 1:100000 cells, and adds that the latest research indicates that some patients can be considered cured after a long period of effective suppression.

That said, he cautions that it is crucial to constantly and consistently measure the level of leukaemia in patients on TKI’s, to ensure that the cells are responding to the drugs.

TKI’s do not make the Leukaemia go away and stay away. Rather, they enable patients to manage the disease, provided that they remain on the medication and continually measure their body’s response to the medication.

Trevor Steyn, CML survivor for 25 years, Patient Leader and founder of CMLSA, a local organisation which aims to provide help and support to CML patients and their loved ones, adds that most patients diagnosed with CML will require lifelong treatment in the form of TKIs.

Although TKI’s are generally well tolerated by most patients – certainly they are less rigorous than chemotherapy – some patients do present with side effects, including severe rashes, muscle pains, liver dysfunction, diarrhea and fluid retention.

“Strict medication adherence is required to achieve and maintain a good response to treatment, and the reduction and management of potential side effects is essential to maintain a good quality of life,” says Steyn.

There are, however, a number of TKIs available on the market, allowing patients to find one that works best for them and their body.

In addition, CMLSA aims to ease the treatment process for those diagnosed with CML, by not only providing access to information about the disease and supporting them in securing the best treatment, but also acting on behalf of patients when it comes to securing the necessary funding for the treatment.

“In South Africa, state patients only have access to first and second line treatments through assistance programmes since the cost of the TKI’s are quite high,” he says.

Steyn hastens to add, however, that patient outcomes are generally positive if patients comply with therapy plans.

In fact, due to the dramatic success rate of TKIs in the treatment of CML, it is estimated that there will be more than 250 000 CML patients living with CML in the US by the year 2040, says Professor Louw.

“TKI’s have improved the average survival of CML from less than three years to well over ten years, and maybe as much as 30 years,” concludes Dr Brittain.

A true miracle of modern medicine. 

If you are diagnosed with CML, says Professor Vernon Louw:

1. Find a specialist that has experience in leukaemia, specifically CML – not all cancer doctors treat leukaemia patients regularly.

2. Get information from the right sources: Ask your clinical haematologist or oncologist; do not just Google it, as there is a lot of misleading information on the Internet.

3. Join a support group.

4. Become an advocate for cancer.

5. Support organisations such as ‘Campaigning for Cancer’ (lauren@campaign4cancer.co.za) and CMLSA (catherina.scheepers@themaxfoundation.org)

6. If you are told that there are no more options, ask whether any clinical trials are being conducted.

7. Last but not least, remember that there is always hope!


[i] American Cancer Society, What are the risk factors for Chronic Myeloid Leukemia? Available at: http://www.cancer.org/cancer/leukemia-chronicmyeloidcml/detailedguide/leukemia-chronic-myeloid-myelogenous-risk-factors Last Medical Review: 06/04/2012
Last Revised: 01/18/2013

[ii] American Cancer Society, How is Chronic Myeloid Leukemia diagnosed? Available at: http://www.cancer.org/cancer/leukemia-chronicmyeloidcml/detailedguide/leukemia-chronic-myeloid-myelogenous-diagnosis Last Medical Review: 06/04/2012
Last Revised: 01/18/2013

[iii] American Cancer Society, Targeted therapies for Chronic Myeloid Leukemia. Available at: http://www.cancer.org/cancer/leukemia-chronicmyeloidcml/detailedguide/leukemia-chronic-myeloid-myelogenous-treating-targeted-therapies Last Medical Review: 06/04/2012
Last Revised: 01/18/2013