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Understanding Chronic Lymphocytic Leukemia

Different types of cancer cells behave differently. So they need different types of treatment. If you have leukemia, it is considered either acute or chronic, depending on how fast the number of leukemia cells increases. The most common leukemias develop from lymphoid (lymphocyte) cells or myeloid (myelocyte) cells. By looking at these factors, a doctor can classify most cases of leukemia into 1 of the types below. Chronic lymphocytic leukemia (CLL) is 1 of the most common types.

Types of leukemia

Here are various types of leukemia. The first 4 are the most common:

  • Acute myeloid leukemia (AML)

  • Acute lymphocytic leukemia (ALL)

  • Chronic myeloid leukemia (CML)

  • CLL

  • Hairy cell leukemia

Confirming your diagnosis

Immunophenotyping is 1 test that helps confirm the type of leukemia you have and what your prognosis is.

For this test, your doctor takes a blood sample or does a bone marrow aspiration to get a bone marrow sample from you. Immunophenotyping helps pinpoint which type of white blood cell has become malignant. It measures the types and amounts of antigens on the surfaces of leukemia cells. Antigens are substances that prompt an immune response. These antigens show the doctor what type of leukemia you have and how the leukemia may grow or spread. Results from this test may take a few days. In some cases, immunophenotyping is used to check progress during treatment.

What is CLL?

CLL is found almost exclusively in adults. It is rare in people younger than age 40 and is extremely rare in children. Most develop the disease after age 60. This slow-growing type of leukemia is caused by a defect in a type of white blood cells called lymphocytes. Too many lymphocytes can result in a decrease in your red blood cell and platelet counts.