Myeloid Leukaemia

Myeloid leukaemia is a serious condition that develops when the normal process of blood cell production is disrupted. It occurs when abnormal myeloid cells, which are precursors to red blood cells, platelets, and certain types of white blood cells, grow uncontrollably in the bone marrow. This uncontrolled growth interferes with the production of healthy blood cells, leading to a range of symptoms and complications.

What is Myeloid Leukaemia?

Myeloid leukaemia, also known as acute myeloid leukaemia (AML) or acute myelogenous leukaemia, is a cancer that affects the myeloid lineage of blood cells. In this condition, the bone marrow produces abnormal myeloid cells, known as blasts, which accumulate in the bone marrow and blood. These blasts fail to mature properly and cannot function like normal blood cells. As the number of blasts increases, they disrupt the production of healthy red blood cells, white blood cells, and platelets, leading to symptoms of myeloid leukaemia such as anaemia, recurrent infections, and easy bruising or bleeding. A diagnosis of AML leukaemia is made through various tests, including blood tests, bone marrow aspiration, and biopsy.

Myeloid leukaemia can be classified into several subtypes based on the type of cell affected and the degree of maturity of the cancer cells. The main subtypes of myeloid leukaemia include:

• Acute myeloid leukaemia (AML): AML is a rapidly progressing form of myeloid leukaemia, characterised by the presence of immature, abnormal myeloid cells called myeloblasts. These cells multiply quickly and accumulate in the bone marrow and blood, crowding out healthy blood cells. AML requires immediate treatment to prevent further progression and complications. It can be further classified into subtypes, such as acute promyelocytic leukaemia (APL), which is characterised by the presence of auer rods in the cytoplasm of the abnormal cells.

• Chronic myeloid leukaemia (CML): CML is a slower-growing form of myeloid leukaemia compared to AML. It is characterised by the presence of more mature, but still abnormal, myeloid cells in the bone marrow and blood. CML typically progresses gradually over months or years, and patients may not experience symptoms in the early stages of the disease.

Myeloid leukaemia, particularly acute myeloid leukaemia (AML), presents with a variety of symptoms that can be non-specific and similar to those of other illnesses. Some of the common symptoms include:

• Fatigue and weakness: Patients often experience significant fatigue due to anaemia (a deficiency of red blood cells), which can lead to reduced oxygen delivery to tissues.

• Frequent infections: Due to a decrease in functional white blood cells, individuals may find themselves more susceptible to infections, often experiencing recurrent or severe infections.

• Easy bruising or bleeding: Myeloid leukaemia can cause a shortage of platelets (thrombocytopenia), leading to easy bruising, prolonged bleeding from minor cuts, or spontaneous bleeding, such as nosebleeds or gum bleeding.

• Weight loss: Unexplained weight loss can occur as the body struggles to cope with the disease and its effects on metabolism.

• Fever and night sweats: Patients may experience persistent fevers and night sweats, which can be related to the body’s immune response to the cancer.

• Bone pain: Some people may experience bone pain or discomfort, which may be due to the proliferation of abnormal cells in the bone marrow.

• Swollen lymph nodes: Enlarged lymph nodes may occur as the body attempts to fight off the disease or due to the infiltration of leukaemia cells.

• Pale skin: Pallor can result from anaemia, leading to a noticeable decrease in skin colour.

• Shortness of breath: As the condition progresses and red blood cell levels drop, individuals may experience difficulty breathing, especially during exertion.

• Abdominal discomfort: An enlarged spleen or liver may cause discomfort or a feeling of fullness in the abdomen.

The exact cause of myeloid leukaemia is not fully understood, but several factors are believed to contribute to its development. These include:

• Genetic mutations: Acquired mutations in the DNA of blood cells play a significant role in the onset of myeloid leukaemia. These mutations can occur over time and are often linked to specific genes such as FLT3, NPM1, and TP53. Additionally, inherited genetic conditions like Down syndrome or Fanconi anaemia can increase the risk of developing leukaemia.

• Environmental exposures: High levels of radiation, such as from radiation therapy for other cancers, and chemical exposure to benzene—found in tobacco smoke and industrial emissions—can increase the risk of developing leukaemia.

• Age: Age is a significant factor, as myeloid leukaemia is more commonly diagnosed in older adults. The risk increases markedly after the age of 60.

• Smoking: Tobacco use is a well-established risk factor for various cancers, including myeloid leukaemia. The harmful substances in tobacco can contribute to the mutations that lead to cancer development.

• Chronic blood disorders: Conditions such as myelodysplastic syndromes or polycythemia vera can predispose individuals to the development of myeloid leukaemia. These disorders often involve abnormalities in blood cell production.

• Immune system disorders: A weakened immune system, whether due to diseases like HIV/AIDS or from immunosuppressive treatments, can increase the risk of leukaemia.

Several factors have been identified that can increase an individual's risk of developing myeloid leukaemia, including:

• Certain genetic conditions, such as Fanconi anaemia and Down syndrome

• Age (over 60 years)

• Previous chemotherapy or radiation therapy

• Exposure to certain chemicals, such as benzene

• Smoking

• Having other blood disorders, such as myelodysplastic syndromes or myeloproliferative neoplasms

While myeloid leukaemia cannot be prevented, certain measures can help reduce the risk and promote overall health. These include:

• Balanced nutrition: A balanced diet rich in fruits, vegetables, whole grains, and lean proteins can support immune health. Antioxidant-rich foods may help reduce oxidative stress.

• Physical activity: Regular exercise is linked to better overall health and may lower cancer risk. Aim for at least 150 minutes of moderate exercise weekly.

• Smoking cessation: Tobacco use is a known risk factor for many cancers, including leukaemia. Quitting smoking can significantly reduce health risks.

• Limit alcohol consumption: Excessive alcohol intake can weaken the immune system and may increase cancer risk.

• Limit chemical exposure: Limit exposure to industrial chemicals and solvents such as benzene, which is associated with an increased risk of leukaemia.

• Limit radiation exposure: Minimise unnecessary medical imaging that involves radiation and avoid environments with high radiation levels.

• Manage chronic conditions: Effectively manage chronic illnesses, such as diabetes or autoimmune disorders, as they may increase the risk of leukaemia.

• Infection prevention: Maintaining a strong immune system through vaccinations and hygiene practices can help prevent infections that may trigger cancer development.

Diagnosing myeloid leukaemia involves a combination of clinical evaluation, laboratory tests, and imaging studies. The diagnostic tests may include:

• Medical history and physical examination: The diagnostic process begins with a comprehensive medical history and physical examination. Doctors will ask about symptoms such as fatigue, unexplained bruising, frequent infections, and weight loss. During the physical exam, they will check for signs of leukaemia, including swollen lymph nodes, liver, or spleen.

• Blood tests: A complete blood count (CBC) assesses levels of red blood cells, white blood cells, and platelets, with abnormal results potentially indicating leukaemia.

• Bone marrow biopsy: This involves extracting a sample of bone marrow, typically from the hip bone, to evaluate the types and concentrations of cells. This test helps confirm the presence of leukemic cells and assess the disease's extent.

• Cytogenetic testing: Cytogenetic testing involves chromosomal analysis to identify genetic mutations or abnormalities associated with myeloid leukaemia.

• Flow cytometry: Flow cytometry is utilised to analyse the characteristics of cells in a blood sample. This test aids in classifying leukaemia and determining its specific type by identifying distinct cell surface markers.

• Imaging tests: Imaging tests, such as computed tomography (CT) scans or X-rays, may be employed to check for enlarged organs or lymph nodes and to assess any potential complications arising from the disease.

• Molecular testing: Molecular testing focusses on identifying specific gene mutations, such as FLT3 or NPM1. These mutations can influence treatment decisions and provide insights into the disease's prognosis.

• Lumbar puncture (spinal tap): In cases where central nervous system involvement is suspected, a lumbar puncture may be performed. This test analyses cerebrospinal fluid for the presence of leukemic cells, helping to assess the extent of the disease.

The specific treatment plan depends on various factors, including the subtype of AML, the patient's age and overall health, and the presence of specific genetic mutations or cytogenetic abnormalities. Some of the treatment options include:

• Chemotherapy: Chemotherapy involves using medicines to kill cancer cells or stop their growth. Patients typically undergo intensive induction chemotherapy to achieve remission, followed by consolidation therapy to eliminate any remaining leukaemic cells.

• Targeted therapy: Targeted therapies focus on specific genetic mutations or abnormalities in leukaemic cells. For instance, drugs that target FLT3 mutations can be particularly effective in certain types of myeloid leukaemia.

• Stem cell transplantation: For some patients, especially those with high-risk features or relapsed disease, a stem cell transplant (also known as a bone marrow transplant) may be considered. This procedure involves replacing the diseased bone marrow with healthy stem cells, either from the patient (autologous transplant) or a donor (allogeneic transplant).

• Supportive care: This may include transfusions for low blood counts, antibiotics for infections, and medications to manage pain or nausea. Psychosocial support, including counselling and support groups, is also important for patients and families.

Living with myeloid leukaemia, particularly acute myeloid leukaemia (AML), can be challenging both physically and emotionally. Here are a few points to consider:

• Stay informed about your specific type of myeloid leukaemia and its treatment options. Don't hesitate to ask your doctor questions.

• Attend all scheduled medical appointments and follow-ups to closely monitor your condition and adjust treatment as needed.

• Report any new or worsening symptoms to your doctor promptly. Common myeloid leukaemia symptoms include fatigue, fever, easy bruising or bleeding, and bone pain.

• Adhere to your prescribed treatment plan. If you experience side effects, discuss them with your doctor to find ways to manage them effectively.

• Take care of your overall health by eating a balanced diet, staying hydrated, getting enough rest, and engaging in light physical activity as tolerated.

• Seek emotional support from loved ones, support groups, or mental health professionals to cope with the psychological impact of living with leukaemia.

If you experience any symptoms suggestive of myeloid leukaemia, such as persistent fatigue, unexplained weight loss, recurrent infections, easy bruising or bleeding, shortness of breath, or bone pain, it's important to see a doctor promptly for evaluation. Additionally, if you have already been diagnosed with AML or CML and notice any changes in your symptoms, side effects from treatment, or overall health status, don't hesitate to contact your doctor.

• Myeloid leukaemia is a type of blood cancer that affects the myeloid cells in the bone marrow.

• The two main types of myeloid leukaemia are chronic myeloid leukaemia (CML) and acute myeloid leukaemia (AML).

• Symptoms of myeloid leukaemia can include fatigue, weight loss, fever, and easy bruising or bleeding.

• Diagnosis of myeloid leukaemia typically involves blood tests, bone marrow aspiration and biopsy, and genetic testing.

• Treatment for myeloid leukaemia depends on the type and stage of the disease but may include targeted therapy, chemotherapy, and stem cell transplantation.

• The prognosis for myeloid leukaemia varies depending on factors such as age, overall health, and response to treatment but advances in targeted therapies have improved outcomes for many patients.

• Living with myeloid leukaemia requires ongoing management, follow-up care, and support for both physical and emotional well-being.