ALL is leukemia that affects lymphocytes, a type of white blood cell. It is not a single disease, but a group of related diseases. These are the three subtypes of ALL.
L1. This type is most common in children.
L2. This type is most common in adults.
L3. This is the most aggressive type and is also called Burkitt-type leukemia.
ALL can also be divided into more specific classifications.
Early Pre-B ALL
Mature B-cell ALL (Burkitt-type leukemia)
Mature T-cell ALL