In Promyelocytic Leukemia, all of the following are features, except:
**Core Concept**
Promyelocytic Leukemia, specifically Acute Promyelocytic Leukemia (APL), is a subtype of acute myeloid leukemia (AML) characterized by the accumulation of immature granulocytes called promyelocytes in the bone marrow and peripheral blood. APL is often associated with chromosomal translocations involving the retinoic acid receptor-alpha (RARα) gene.
**Why the Correct Answer is Right**
The correct answer is related to the pathophysiology of APL. APL is known for its association with disseminated intravascular coagulation (DIC), which is a result of the release of tissue factor from the abnormal promyelocytes. This leads to a hypercoagulable state and thrombosis. Additionally, APL is often associated with a specific chromosomal translocation, t(15;17), which fuses the PML gene with the RARα gene.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is often a distractor in APL questions. However, APL is indeed characterized by hypofibrinogenemia, which is a result of the DIC. Therefore, this option is incorrect.
**Option B:** This option is also incorrect. APL is often associated with thrombocytopenia, which is a result of the DIC and bone marrow failure.
**Option C:** This option is incorrect. APL is indeed characterized by a specific chromosomal translocation, t(15;17), which fuses the PML gene with the RARα gene.
**Clinical Pearl / High-Yield Fact**
A key clinical feature of APL is its response to all-trans retinoic acid (ATRA) therapy, which induces differentiation of the promyelocytes into mature granulocytes. This is a critical aspect of APL management.
**Correct Answer: A.**