What Is Leukemia? Understanding the Causes, Symptoms, and Risk Factors of Blood Cancer

Leukemia is a type of malignant blood disorder that originates at the stem cell level in the bone marrow. It occurs when the body's process for producing healthy blood cells becomes disrupted due to uncontrolled proliferation, impaired differentiation, and resistance to programmed cell death (apoptosis). As a result, large numbers of abnormal white blood cells—known as leukemia cells—accumulate in the bloodstream and bone marrow, crowding out normal red blood cells, platelets, and healthy white blood cells. This interference with normal hematopoiesis leads to a range of serious health complications.

Common Symptoms of Leukemia

Patients with leukemia often experience a variety of systemic symptoms, primarily caused by the suppression of normal blood cell production. The most frequent clinical manifestations include:

Anemia

A shortage of red blood cells leads to anemia, which can cause fatigue, weakness, pale skin, shortness of breath, and dizziness. These symptoms arise because the body's tissues are not receiving enough oxygen.

Bleeding and Bruising

Due to low platelet counts (thrombocytopenia), individuals may suffer from easy bruising, prolonged bleeding from minor cuts, frequent nosebleeds, or even internal bleeding in severe cases.

Infections

Even though there may be an overproduction of white blood cells, these cells are often dysfunctional. This impairs the immune system, making patients highly susceptible to recurrent or severe infections, including respiratory and urinary tract infections.

Potential Causes and Risk Factors

The exact cause of leukemia remains unclear, but researchers have identified several contributing factors that may increase the likelihood of developing the disease.

Viral Infections

Certain viruses, such as the human T-cell leukemia virus (HTLV-1), have been directly linked to specific types of leukemia. These viruses can alter the genetic material of blood cells, triggering malignant transformation.

Chemical Exposure

Long-term exposure to industrial chemicals like benzene—a substance commonly found in gasoline, rubber manufacturing, and some cleaning agents—is strongly associated with an increased risk of leukemia, particularly acute myeloid leukemia (AML).

Radiation Exposure

High levels of ionizing radiation, whether from nuclear accidents, medical treatments, or occupational exposure, can damage DNA in bone marrow cells and significantly elevate the risk of developing leukemia.

Genetic Predisposition

While most cases are not inherited, certain genetic disorders such as Down syndrome and Li-Fraumeni syndrome are known to increase susceptibility. Additionally, family history of blood cancers may suggest a hereditary component in some individuals.

Understanding leukemia involves recognizing its complex nature—spanning biological, environmental, and genetic influences. Early diagnosis and advances in targeted therapies, immunotherapy, and stem cell transplantation continue to improve survival rates and quality of life for patients worldwide.