Types of Acute Lymphocytic Leukemia

Acute Lymphocytic Leukemia (ALL) is leukemia that affects lymphocytes, a type of white blood cell. It is not a single disease, but a group of related diseases. In the past, doctors divided ALL into the following three subtypes, based mainly on how the leukemia cells looked under the microscope:

• L1. Most common in children

• L2. Most common in adults

• L3. Most aggressive type; also called Burkitt-type leukemia

Newer lab tests now allow doctors to divide ALL into more specific classifications, based on the type of lymphocyte the disease starts in and how mature the cells are.

• Early Pre-B ALL

• Common ALL

• Pre-B ALL

• Mature B-cell ALL (Burkitt-type leukemia)

• Pre-T ALL

• Mature T-cell ALL