Chronic myelogenous leukaemia

Overview Of Chronic myelogenous leukaemia

Chronic myelogenous leukemia (CML) is a type of cancer that affects the bone marrow and blood. It is characterized by the uncontrolled production of white blood cells, which accumulate in the bloodstream. CML typically progresses in three phases: chronic phase, accelerated phase, and blast crisis. The disease is most commonly associated with a genetic mutation that leads to the formation of the Philadelphia chromosome, which results from a translocation between chromosomes 9 and 22. This genetic abnormality leads to the production of an abnormal protein (BCR-ABL), which drives the growth of leukemia cells. CML often develops slowly, with symptoms appearing gradually over time.

Causes of Chronic myelogenous leukaemia

• The primary cause of CML is a genetic mutation that occurs in the DNA of blood-forming cells in the bone marrow. This mutation leads to the creation of the Philadelphia chromosome, which is present in most CML cases. The Philadelphia chromosome results from a translocation between chromosome 9 and chromosome 22, fusing two genes, BCR and ABL, into a single abnormal gene. This gene produces an abnormal protein (BCR-ABL), which triggers uncontrolled cell division and the development of leukemia. While the specific trigger for the formation of the Philadelphia chromosome remains unclear, factors such as exposure to high levels of radiation or certain chemicals may increase the risk of developing CML.

Risk Factors of Chronic myelogenous leukaemia

• Certain factors can increase the likelihood of developing CML. These include: - Age: CML is more common in adults over the age of 60, though it can occur at any age. - Gender: Men are slightly more likely to develop CML than women. - Exposure to radiation: High levels of ionizing radiation, such as from nuclear accidents or certain cancer treatments, have been linked to an increased risk of CML. - Family history: While most cases of CML are not inherited, a family history of leukemia may slightly increase the risk. - Chemical exposure: Long-term exposure to certain chemicals, such as benzene, has been associated with a higher risk of developing CML.

Prevention of Chronic myelogenous leukaemia

• There is currently no known way to prevent CML, as its exact cause is not fully understood. However, minimizing exposure to known risk factors can help reduce the likelihood of developing the disease. These risk factors include excessive radiation exposure, certain chemicals, and a family history of leukemia. Regular medical check-ups and early screening may help detect CML in its early stages, particularly for individuals who have a higher risk due to exposure to radiation or chemicals.

Prognosis of Chronic myelogenous leukaemia

• With the development of TKIs, the prognosis for patients with CML has improved dramatically. The survival rate for CML patients has increased to over 90% with appropriate treatment, and many patients can live a near-normal life expectancy. Early diagnosis and consistent use of medications can keep the disease in remission for many years. However, the prognosis can vary depending on the phase of CML at diagnosis. Patients diagnosed in the chronic phase generally have a better outcome than those diagnosed in the accelerated or blast crisis phases, where the disease is more aggressive and harder to treat. Regular follow-ups are essential for monitoring the disease and adjusting treatment as needed.

Complications of Chronic myelogenous leukaemia

• Although many individuals with CML respond well to treatment, there are potential complications. These include: - Blast crisis: A phase in which the disease becomes more aggressive and behaves similarly to acute leukemia. This is a serious complication and requires more intensive treatment. - Resistance to TKIs: In some cases, CML cells may develop resistance to treatment, leading to relapse. Alternative TKIs or combination therapies may be necessary in these cases. - Side effects of treatment: TKIs can cause side effects, including fluid retention, liver problems, and heart issues. Regular monitoring is important to manage these side effects. - Increased risk of infections: As CML affects white blood cell production, patients may have a weakened immune system, making them more susceptible to infections.

Related Diseases of Chronic myelogenous leukaemia

• CML is a form of leukemia, and while it shares common features with other forms of leukemia, it is distinct due to the presence of the Philadelphia chromosome. Related diseases include: - Acute myelogenous leukemia (AML): A more aggressive form of leukemia that develops rapidly and requires intensive treatment. Unlike CML, AML does not typically involve the Philadelphia chromosome. - Chronic lymphocytic leukemia (CLL): Another chronic form of leukemia, but CLL affects lymphocytes, not myeloid cells like CML. It progresses more slowly than CML and is more common in older adults. - Myelodysplastic syndromes (MDS): A group of disorders caused by poorly formed or dysfunctional blood cells, which can sometimes evolve into acute leukemia, including CML.

Treatment of Chronic myelogenous leukaemia

The primary treatment for CML is the use of tyrosine kinase inhibitors (TKIs), which specifically target the BCR-ABL protein caused by the Philadelphia chromosome. Imatinib (Gleevec) is the first-line treatment and has significantly improved survival rates for CML patients. Other TKIs, such as dasatinib, nilotinib, and bosutinib, are also available for patients who are resistant or intolerant to imatinib. In some cases, chemotherapy may be used, particularly in the accelerated or blast crisis phases of the disease. Stem cell or bone marrow transplantation may be considered for patients who do not respond to TKIs or experience relapse. The choice of treatment depends on the phase of CML, the patient’s overall health, and how well they respond to initial therapies.