Acute myeloid leukaemia (AML) is a rare and aggressive blood cancer that develops rapidly when the bone marrow begins producing abnormal white blood cells. These faulty cells crowd out healthy blood cells, weakening the body’s ability to fight infection, carry oxygen, and control bleeding. Though it can affect people of any age, AML most commonly strikes adults over 60, making it a disease that demands quick recognition and urgent treatment.
Epidemiology
Acute myeloid leukaemia is uncommon compared to many other cancers, accounting for only about one percent of all cancers diagnosed in the United States. Yet among the different types of acute leukaemia affecting adults, it is the most frequently encountered form. According to available data, approximately four adults in every 100,000 develop AML each year. In children, the disease is even rarer, with roughly 1,160 children receiving this diagnosis annually.[2][3][6]
Age is one of the strongest patterns in AML occurrence. The disease predominantly affects older adults, particularly those aged 60 and above. However, younger adults and even children can develop AML, though this happens far less often. Some statistics show that for individuals aged 20 or older, the five-year survival rate stands at approximately 27 percent, reflecting the aggressive nature of the condition and the challenges involved in treating it.[3][15]
There are no widely documented major differences between men and women in terms of how common AML is, though some sources indicate that men may be slightly more at risk. Geographic and ethnic variations have not been extensively detailed in the available information, but understanding who is most likely to develop AML helps healthcare providers remain vigilant and begin treatment quickly when symptoms appear.[7]
Causes
Experts do not fully understand what triggers acute myeloid leukaemia. The disease arises when certain genes or chromosomes—structures inside cells that carry genetic information—undergo changes known as mutations. These mutations lead the bone marrow to produce abnormal white blood cells instead of healthy ones. However, in most cases, the reason why these genetic changes occur remains unknown.[2][4][15]
The genetic alterations linked to AML can happen in different ways. Some occur spontaneously during a person’s lifetime when something alters their DNA. Others may be inherited, meaning a person is born with a genetic disorder that increases their likelihood of developing leukaemia. In rare instances, changes in certain genes can occur in a parent’s sperm or egg before conception, potentially affecting the child later in life.[2][15]
What makes AML so dangerous is how these genetic changes disrupt the normal production of blood cells. The bone marrow, which is the soft, spongy tissue inside most bones, usually functions like a carefully controlled factory, generating just the right number of red blood cells, white blood cells, and platelets. In AML, the bone marrow churns out immature white blood cells called myeloblasts or myeloid blasts. These abnormal cells do not mature properly and fail to fight infections as healthy white blood cells do. Instead, they multiply rapidly and crowd out the healthy cells, leaving less room for functional red blood cells, platelets, and other white blood cells. This imbalance leads to serious complications such as infections, anaemia (a lack of red blood cells), and uncontrolled bleeding.[2][6][15]
AML is not contagious and cannot be transmitted from person to person. It is not caused by bacteria or viruses that spread through contact. The disease develops internally due to abnormal cell behaviour triggered by genetic changes in the bone marrow.[2]
Risk Factors
While the exact cause of acute myeloid leukaemia remains unclear, several factors are known to increase the risk of developing the disease. Understanding these risk factors does not mean someone will definitely develop AML, but it does help identify individuals who might benefit from closer monitoring or earlier medical attention if symptoms appear.[4][6][7]
Smoking is one of the most well-documented risk factors for AML, particularly in people over the age of 60. Tobacco smoke contains a variety of harmful chemicals that can damage DNA, making genetic mutations more likely. Exposure to benzene, a chemical found in cigarette smoke as well as certain manufacturing and industrial settings, also raises the risk. People who work in environments where benzene is present may have a higher chance of developing AML over time.[6][9]
Previous cancer treatment can increase the likelihood of developing AML later in life. Individuals who have undergone chemotherapy—a treatment that uses powerful drugs to kill cancer cells—or radiotherapy—a treatment that uses high-energy radiation to destroy cancer cells—may find that these treatments, while effective against their original cancer, can damage healthy cells and increase the risk of developing a second cancer such as AML. Exposure to very high levels of radiation, whether from medical treatments or environmental sources, also contributes to this risk.[6][7][9]
Certain pre-existing blood disorders and genetic conditions can make AML more likely. For instance, people with conditions like myelodysplastic syndromes (MDS)—disorders in which the bone marrow does not produce enough healthy blood cells—have an elevated risk of progressing to AML. Some genetic conditions, such as Down’s syndrome, also increase susceptibility to the disease. Children or adults born with these conditions may require closer observation by healthcare providers.[6][9]
Age is another significant risk factor. As mentioned earlier, AML is most common in older adults, particularly those over 75. Younger individuals and children can develop the disease, but it is far less frequent in these age groups. Being male also appears to slightly increase the risk of developing AML, though the reasons for this are not entirely clear.[7][15]
Symptoms
The symptoms of acute myeloid leukaemia often begin subtly, resembling the signs of a common cold or flu that simply does not go away. Because AML develops quickly and aggressively, these early symptoms usually worsen over a matter of weeks, prompting individuals to seek medical attention.[2][4][9]
One of the earliest and most common complaints is persistent tiredness or fatigue. People with AML often feel exhausted even after resting, and this weariness can interfere with daily activities. This overwhelming tiredness occurs because the abnormal cells in the bone marrow prevent the production of enough healthy red blood cells, which are responsible for carrying oxygen throughout the body. Without adequate oxygen, every organ and muscle struggles to function properly, leaving the person feeling weak and drained.[2][4][9]
As the disease progresses, individuals may notice unusual bruising or bleeding. Bruises might appear with only minor bumps or no apparent injury at all. Bleeding can occur in unexpected places, such as frequent nosebleeds, bleeding gums when brushing teeth, or tiny red spots on the skin called petechiae. These symptoms happen because AML reduces the number of platelets in the blood. Platelets are small cell fragments that help blood clot and stop bleeding. Without enough platelets, even minor injuries can result in prolonged or excessive bleeding.[2][4][15]
Frequent infections or infections that refuse to clear up are another hallmark of AML. The abnormal white blood cells produced by the diseased bone marrow cannot effectively fight off bacteria, viruses, or other germs. As a result, people with AML may develop infections more often than usual, and these infections may persist despite treatment. Fever, night sweats, and a general feeling of being unwell often accompany these infections.[2][4][9]
Other symptoms can include shortness of breath, known medically as dyspnoea, which occurs because the body lacks sufficient red blood cells to deliver oxygen efficiently. People may feel breathless even during light activities or while resting. Pale skin is another visible sign, resulting from anaemia. Dizziness, headaches, and feeling unusually cold are also common complaints.[2][4][15]
Some individuals experience bone pain, back pain, or abdominal pain as leukaemia cells accumulate in the bone marrow or spread to other parts of the body. Swollen lymph nodes, which are small glands that help the immune system, may become noticeable in the neck, underarms, or groin. Unexplained weight loss and loss of appetite are also possible, further contributing to a general sense of feeling unwell.[2][15]
In some cases, AML can spread beyond the blood and bone marrow to other organs, including the central nervous system (the brain and spinal cord), the skin, or the gums. When this happens, additional symptoms may develop, such as headaches, confusion, or skin lesions. Rarely, leukaemia cells may form a solid tumour called a myeloid sarcoma.[6][10]
Because many of these symptoms resemble those of less serious illnesses, it is easy to dismiss them initially. However, if symptoms persist, worsen, or occur together, it is crucial to consult a healthcare provider. Early detection and prompt treatment can make a significant difference in managing AML.[4][9]
Prevention
Preventing acute myeloid leukaemia is challenging because the exact cause of the disease is not known in most cases. However, there are steps individuals can take to reduce their risk or detect problems early, especially if they have known risk factors.[6][7]
Avoiding smoking is one of the most important preventive measures. Smoking not only increases the risk of AML but also contributes to a wide range of other health problems, including lung cancer and heart disease. Quitting smoking or never starting in the first place can significantly lower the risk of developing leukaemia and improve overall health. For individuals who smoke, seeking support from healthcare providers, support groups, or smoking cessation programmes can make quitting easier.[6][9]
Limiting exposure to benzene and other harmful chemicals is another way to reduce risk. People who work in industries where benzene is used should follow safety guidelines, wear protective equipment, and ensure proper ventilation in the workplace. Employers have a responsibility to maintain safe working conditions and reduce workers’ exposure to hazardous substances.[6][9]
For individuals who have undergone chemotherapy or radiotherapy for a previous cancer, there is no way to entirely eliminate the risk of developing AML as a secondary cancer. However, healthcare providers can monitor these patients more closely for signs of blood disorders or leukaemia. Regular follow-up appointments and blood tests can help detect problems early, when they may be easier to treat.[6][7]
People with pre-existing blood disorders or genetic conditions that increase the risk of AML should work closely with their healthcare team. Regular monitoring and early intervention can sometimes prevent progression to leukaemia or catch the disease in its earliest stages. Genetic counselling may also be helpful for families with a history of genetic conditions linked to AML, providing guidance on risks and screening options.[6]
Maintaining a healthy lifestyle, including eating a balanced diet, staying physically active, and managing stress, supports overall health and strengthens the immune system. While these measures do not specifically prevent AML, they contribute to general well-being and may help the body cope better with illness if it occurs.[24]
There are no routine screening tests for acute myeloid leukaemia in the general population. Unlike some cancers that can be detected through regular screening, AML is typically diagnosed only after symptoms appear. For this reason, recognising symptoms early and seeking medical attention promptly is crucial.[6][9]
Pathophysiology
To understand how acute myeloid leukaemia disrupts the body, it helps to know how healthy blood cells are normally made. The bone marrow, found in the centre of most bones, acts as the body’s blood cell factory. It contains special cells called stem cells, which are immature cells with the potential to develop into different types of blood cells. A stem cell can become a myeloid stem cell or a lymphoid stem cell.[6][10][15]
Myeloid stem cells go through several stages of development before maturing into three essential types of blood cells. Red blood cells carry oxygen from the lungs to every tissue and organ in the body. White blood cells, particularly types called granulocytes and monocytes, help the immune system fight infections, respond to allergens, and manage inflammation. Platelets are tiny fragments that help blood clot and prevent excessive bleeding. This production process is carefully regulated, ensuring the body has just the right number of each type of cell at any given time.[6][10][13]
In acute myeloid leukaemia, this orderly process breaks down. Genetic mutations cause the bone marrow to produce large numbers of abnormal myeloid cells called myeloblasts. These myeloblasts are immature and do not develop into healthy, functional white blood cells. Instead, they accumulate rapidly in the bone marrow and spill into the bloodstream. As their numbers grow, they crowd out the healthy stem cells, leaving less room for the bone marrow to produce normal red blood cells, white blood cells, and platelets.[2][3][6]
This crowding effect leads to the symptoms and complications associated with AML. Without enough healthy red blood cells, the body cannot transport sufficient oxygen, resulting in anaemia, fatigue, shortness of breath, and pale skin. A lack of functional white blood cells weakens the immune system, making the person vulnerable to frequent and persistent infections. A shortage of platelets impairs the blood’s ability to clot, leading to easy bruising, prolonged bleeding from minor cuts, nosebleeds, and bleeding gums.[2][6][10]
The leukaemia cells themselves can also spread beyond the bone marrow and blood. They may travel to other parts of the body, including the central nervous system (the brain and spinal cord), the skin, and the gums. In some cases, leukaemia cells clump together to form a solid tumour known as a myeloid sarcoma. This spread can cause additional symptoms and complications depending on which organs or tissues are affected.[6][10]
Because AML is an aggressive disease, these changes happen quickly. The disease often worsens over a matter of weeks, leading to a rapid decline in health. This fast progression is what makes AML so dangerous and why early diagnosis and prompt treatment are so critical. Without treatment, the accumulation of abnormal cells can overwhelm the body’s normal functions, leading to life-threatening complications.[2][6][9]
There are several subtypes of AML, classified based on the specific types of cells affected and the genetic mutations involved. For example, acute promyelocytic leukaemia (APL) is a subtype in which certain genes on chromosomes switch places, creating a unique genetic abnormality. Other subtypes include cancers that affect cells producing different types of white blood cells, red blood cells, or platelets. Each subtype can behave slightly differently and may respond differently to treatment, which is why detailed testing is essential for diagnosing and managing AML.[2][6][15]