Definition: Acute lymphocytic leukemia (ALL) is a fast-moving cancer that affects the lymphoid white blood cells. It is the most common form of leukemia among children, although it also strikes adults. For more information, see leukemia.
Also Known As: Acute lymphoblastic leukemia, acute lymphoid leukemia, ALL
Alternate Spellings: Acute lymphocytic leukaemia, acute lymphoblastic leukaemia, acute lymphoid leukaemia