What Is Leukemia?

Leukemia is a type of cancer that affects the body's blood-forming tissues, including the bone marrow and the lymphatic system. This disease usually starts in the white blood cells, which play a crucial role in fighting infections. In leukemia, however, the bone marrow produces abnormal white blood cells that don't function properly, disrupting the body's ability to fight infections and produce other essential blood cells.

Types of Leukemia

Leukemia is categorized based on how quickly it progresses and which type of white blood cell is affected. The main types include:

• Acute Lymphoblastic Leukemia (ALL): The most common type of leukemia in young children, though it can also affect adults.
• Acute Myeloid Leukemia (AML): Found in both adults and children, AML is the most common acute leukemia in adults.
• Chronic Lymphocytic Leukemia (CLL): This type mainly affects older adults, typically those over 55, and is the most common chronic leukemia in adults.
• Chronic Myeloid Leukemia (CML): Primarily an adult disease, CML can progress slowly with few symptoms initially, but it can accelerate over time.

What Causes Leukemia?

The exact cause of leukemia is still not fully understood. It is believed to be a combination of genetic and environmental factors. In leukemia, cells develop mutations in their DNA, causing them to grow uncontrollably and live longer than they should. These abnormal cells crowd out healthy blood cells in the bone marrow, leading to various symptoms associated with leukemia.

Risk Factors for Leukemia

Certain factors may increase the likelihood of developing leukemia, including:

• Previous Cancer Treatment: Chemotherapy and radiation therapy for other cancers can increase leukemia risk.
• Genetic Disorders: Conditions like Down syndrome are linked to a higher risk.
• Exposure to Chemicals: Certain chemicals, like benzene, are known to be linked to leukemia.
• Smoking: Tobacco use has been associated with an increased risk of acute myeloid leukemia (AML).
• Family History: A family history of leukemia can slightly increase the risk.

However, many people with these risk factors never develop leukemia, and some people without any known risk factors do. This suggests much is still to be learned about what causes this disease.

Who Gets Leukemia?

Leukemia can affect anyone, but some groups are more at risk than others. According to the National Cancer Institute, an estimated 59,610 new cases of leukemia were expected in 2023, accounting for about 3% of all new cancer diagnoses in the U.S. As of 2020, there were approximately 490,875 people living with leukemia in the United States.

Connect with a Specialist Today

If you or someone you know has been diagnosed with leukemia, it's vital to find a specialist to receive the best treatment possible. You can search for an AML, ALL, CLL, or CML specialist today in our directory. 

Leukemia Specialist Directory

Further Resources

Looking for trustworthy information on AML or CLL? Join our HealthTree community! We offer up-to-date news, interviews with specialists and informative webinars for patients and care partners. Connect with others and learn more at:

• HealthTree for AML
• HealthTree for CLL

Living with CML or ALL? We're working on expanding our support to you soon. Stay tuned!