What type of AML has a genetic rearrangement of t(15;17)(q22;q11-12)?

The type of acute myeloid leukemia (AML) characterized by the genetic rearrangement t(15;17)(q22;q11-12) is known as acute promyelocytic leukemia (APL), which is classified as AML M3.

This specific translocation results in the creation of the promyelocytic leukemia-retinoic acid receptor alpha (PML-RARA) fusion gene. This fusion gene plays a significant role in the pathogenesis of APL by interfering with normal myeloid differentiation and leading to the accumulation of promyelocytes in the bone marrow. APL has distinct clinical features, including a propensity for bleeding due to coagulopathy, and is treated effectively with all-trans retinoic acid (ATRA) combined with arsenic trioxide, which promote differentiation of the leukemic cells.

To summarize, the presence of the t(15;17) translocation is definitive for diagnosing acute promyelocytic leukemia, aligning with the characteristics and treatment approaches specific to AML M3.