AML-M3 is a subtype of acute myeloid leukemia (AML) according to the French-American-British (FAB) classification. This subtype is also known as Acute Promyelocytic Leukemia (APL). The disease typically arises from a translocation (t(15;17)) between chromosomes 15 and 17. This genetic alteration halts the normal maturation of white blood cells in the bone marrow, leading to the uncontrolled accumulation and proliferation of promyelocytes, an immature type of cell. Its treatment differs significantly from other AML subtypes and generally has a high success rate.