Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia characterized by the accumulation of abnormal white blood cells called promyelocytes. This condition disrupts normal blood cell production, leading to symptoms such as fatigue, bleeding, and increased risk of infections. APL is often associated with a specific genetic mutation involving the promyelocytic leukemia (PML) gene. APL is typically diagnosed through blood tests and bone marrow examination. Treatment usually involves a combination of chemotherapy and targeted therapy, such as all-trans retinoic acid (ATRA), which helps to induce differentiation of the abnormal cells. With appropriate treatment, APL has a favorable prognosis compared to other leukemia types.