What is the treatment for cml?

Answer 1

Chronic Myeloid Leukaemia (CML) is a type of white blood cell cancer. It is diagnosed and monitored using a number of specialised blood tests, some specifically looking for levels of abnormal cell DNA.

CML occurs when damaged cells within a person's bone marrow (where white blood cells are manufactured) begin to produce an abnormal enzyme (production chemical) that disorders the process of making white blood cells. The DNA defect is commonly known as the Philadelphia Chromosome (because that's where it was discovered). The abnormal enzyme this DNA produces causes highly immature and irregular white blood cells to be produced and released into the blood stream. It is this abnormal enzyme that is the target of most current drug therapies.

Almost all patients diagnosed with CML will be treated with a drug called Gleevec (also known as imatinib, from a class of drugs called tyrosine kinase inhibitors, or TKIs). This drug prevents the enzyme from working. It has been prescribed widely for around 7 years. The majority of patients on it do very well, and because it acts specifically on the enzyme involved (unlike chemotherapy) there are few if any side effects in most people. Most patients' blood tests return to normal after a few years on the drug...

The issue is whether patients with 'normal' blood work should stay on the drug or come off it. Because it is a relatively new drug we currently do not know what the potential LONG TERM effects there might be of staying on it. We do not know whether the drug would be harmful to women who are pregnant or breast-feeding, as there is no data on this. We also have no reliable evidence to suggest that coming OFF the drug is beneficial: in some patients, their CML returns once off Gleevec, and in others it does not. This is a choice that patients must make.

In patients who cannot tolerate imatinib, another TKI may be tried. If this fails, then a bone marrow transplant (BMT) may be tried. This is NOT the same as a solid organ transplant (such as a kidney, where most biological family members would be suitable). Bone marrow suitable for transplant may not be found in any family member and may have to come from an unknown donor. A BMT is extremely risky (1 in 5 patients will die during, or shortly after, the procedure). Around 2 in 3 patients will be fully cured of CML forever, but this does potentially come at a cost. The long-term disabilities from BMTs CAN include permanent painful skin inflammation or life-long diarrhoea.

Treatment for CML needs to be the result of joint discussions between patients, the families and expert doctors (usually haematologists).