Acute Promyelocytic Leukemia Overview
Acute promyelocytic leukemia is a rare and aggressive subtype of acute myeloid leukemia. The cancer is characterized by an overproduction of immature blood-forming cells (promyelocytes) in the blood and bone marrow. Eventually, the promyelocytes outnumber the healthy red blood cells, white blood cells and platelets, which can prevent the blood from functioning properly.
Due to groundbreaking treatment advances achieved in recent years, acute promyelocytic leukemia is now considered to be the most curable form of adult leukemia.
Causes of and risk factors for acute promyelocytic leukemia
Acute promyelocytic leukemia is caused by the body’s uncontrolled production of promyelocytes, which results from a gene mutation in a single blood-forming cell. Specifically, a certain tumor suppressor gene known as the promyelocytic leukemia (PML) gene on chromosome 15 fuses with the retinoic acid receptor alpha (RARA) gene on chromosome 17. The rearrangement of genetic material (translocation) between chromosomes 15 and 17 forms an abnormal fusion gene known as PML/RARa.
Although scientists have not yet identified the precise causes of the genetic mutation that leads to the development of acute promyelocytic leukemia, they have confirmed that the condition is acquired and not inherited.
Signs and symptoms of acute promyelocytic leukemia
A telltale symptom of acute promyelocytic leukemia is coagulopathy, a potentially dangerous disorder that interferes with blood clotting and can lead to excessive bleeding, easy bruising and blood clot formation (thrombosis).
Due to possible shortages of healthy red blood cells, white blood cells and platelets along with abnormal protein levels in the bloodstream, acute promyelocytic leukemia can also cause:
- Fever, chills and night sweats (B symptoms)
- Muscle weakness and fatigue
- Anemia and skin pallor
- Loss of appetite
- Unintended weight loss
- Frequent infections
- Pinhead-sized red spots on the skin (petechiae)
Diagnosing acute promyelocytic leukemia
A diagnosis of acute promyelocytic leukemia is usually based on a medical history review, physical examination and lab testing. If symptoms such as easy bleeding or bruising are present, a physician will typically order a complete blood count (CBC) to evaluate the levels of red blood cells, white blood cells and platelets. The diagnostic hallmark of acute promyelocytic leukemia is the presence of PML/RARa.
Acute promyelocytic leukemia treatment
Acute promyelocytic leukemia is a medical emergency. To reduce the risk of complications associated with coagulopathy, such as life-threatening blood clots, treatment should begin as soon as the condition is suspected.
Treatment of acute promyelocytic leukemia differs from that of most other types of acute myeloid leukemia. Usually, it involves the administration of differentiating agents, such as all-trans-retinoic acid (ATRA). These non-chemotherapy drugs target the chromosomal abnormality and destroy the leukemia cells. Usually, the cancer responds well to the initial phase of treatment (induction therapy) and goes into remission. During remission, many patients receive consolidation therapy, which may involve:
- Additional cycles of ATRA
- Traditional chemotherapy
- Intrathecal chemotherapy
- Transfusions of platelets and blood-clotting factors
After completing consolidation therapy, some high-risk patients continue with maintenance therapy for a few years to help prevent a recurrence. Maintenance therapy is intermittent and may involve a combination of ATRA and low-dose chemotherapy.
How Moffitt Cancer Center approaches acute promyelocytic leukemia
Moffitt Cancer Center is a high-volume cancer center, and the multispecialty team in our renowned Malignant Hematology Program has acquired extensive experience in diagnosing and treating all forms of leukemia, including relatively uncommon subtypes such as acute promyelocytic leukemia. We take an individualized approach to cancer care, determining the most appropriate course of action after taking into account the type and stage of the cancer and the patient’s health, preferences and goals.
If you would like to learn more about acute promyelocytic leukemia, you do not need a referral to talk with one of our specialists. When you request an appointment by calling 1-888-663-3488 or submitting a new patient registration form online.