Acute lymphocytic leukemia (ALL) is a type of cancer that originates from the early version of white blood cells in the bone marrow, the soft inner part of the bones. It can also be known as acute lymphoblastic leukemia or acute lymphoid leukemia. The term "acute" refers to the rapid progression of the disease, which can become fatal within weeks or months if left untreated. "Lymphocytic" indicates that the cancer affects a specific type of white blood cell called lymphocytes.

Lymphocytes are a type of white blood cell that plays a critical role in the immune system, which is responsible for defending the body against infections and diseases. Lymphocytes are a key component of the body's immune response and are produced in the bone marrow, where they mature before entering the bloodstream and lymphatic system.

ALL is characterized by the overproduction of immature lymphocytes, known as lymphoblasts or leukemic blasts. These cells multiply rapidly, crowding out healthy cells in the bone marrow and spilling over into the bloodstream. Unlike healthy cells, these leukemic cells are unable to function properly to fight off infections. They can also invade other body organs, causing a variety of symptoms.

Who Gets Acute Lymphocytic Leukemia? 

According to the National Cancer Institute, there will be an estimated 6,540 new cases of ALL in 2023, making up 0.3% of all new cancer diagnoses. In 2020, there were an estimated 111,425 people living with ALL in the United States. ALL is most frequently diagnosed in children, making it the most common type of childhood cancer. The peak incidence of ALL occurs in early childhood, typically between the ages of 2 and 5 years old. ALL can also occur in adults, but it is much less common than other types of leukemia. The incidence decreases with age and is relatively rare in people over 40. Males are slightly more likely to develop ALL than females, and the incidence of ALL is higher in Caucasians than in African Americans or Asian Americans.

Why Do People Get Acute Lymphocytic Leukemia?

The exact cause of ALL is unknown, but certain factors may increase the risk of developing the disease.

These risk factors include:

• Exposure to high levels of radiation: Prolonged exposure to high levels of ionizing radiation, such as that experienced during radiation therapy for other cancers or in the aftermath of a nuclear accident, may increase the risk of developing ALL.
• Certain genetic disorders:
  • Down syndrome
  • Li-Fraumeni syndrome
  • Neurofibromatosis type 1
• A history of certain blood disorders: Individuals who have previously been diagnosed with certain blood disorders, such as myelodysplastic syndrome (MDS) or myeloproliferative neoplasms (MPNs), may have an increased risk of developing ALL.
• A family history of leukemia: In some cases, a family history of leukemia may slightly increase the risk of developing ALL. However, most cases of ALL are not inherited, and the disease is not typically considered a strongly hereditary condition.
• Exposure to chemicals and environmental factors: Some studies have suggested that exposure to certain chemicals, such as benzene and certain pesticides, may be associated with an increased risk of ALL. However, the evidence for these associations is not always clear.
• Gender and age: ALL is more common in children than in adults. In fact, it is one of the most common types of cancer in children. The risk decreases with age, and it is less common in adults. Additionally, males have a slightly higher risk of developing ALL than females.

Despite the risk factors mentioned above, it is important to note that most people with ALL have no known risk factors.

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