What is a characteristic presentation of Promyelocytic Leukemia?

Promyelocytic leukemia, specifically acute promyelocytic leukemia (APL), is characterized by the presence of a specific genetic alteration: the translocation t(15;17). This translocation results in the fusion of the promyelocytic leukemia (PML) gene on chromosome 15 and the retinoic acid receptor alpha (RARA) gene on chromosome 17, creating the PML-RARA fusion protein. This fusion protein plays a crucial role in the pathogenesis of APL by interfering with normal hematopoiesis and leading to the accumulation of abnormal promyelocytes in the bone marrow.

The clinical implications of this translocation are significant, as it not only aids in the diagnosis of APL but also shapes the treatment approach. Patients with APL are often treated with all-trans retinoic acid (ATRA) in conjunction with chemotherapy, which targets the effects of the PML-RARA fusion protein and can induce differentiation of the leukemic cells, leading to remission.

In contrast, other options do not distinctly identify APL. Acute onset of thrombocytopenia is a symptom seen in various types of leukemia and is not specific to APL. Rapid leukocytosis can occur in other forms of acute leukemia but is