Acute Promyelocytic Leukemia (APL) is a sub-type of acute myelogenous leukemia, a cancer of the blood cells. In APL, the blood produces an excessive amount of immature promyelocytes in the bone marrow. Once an extremely fatal form of leukemia, it is now highly treatable thanks to a number of advances in medicine. APL mainly affects young adults and children.
Acute Promyelocytic Leukemia Signs & Symptoms
The most common symptom of APL is anemia, as there are not enough red blood cells and platelets being produced in the bone marrow, which can cause a significant lack of iron in the blood supply.
Other symptoms can include:
- Fatigue, weakness, or shortness of breath
- Dizziness
- Persistent fever
- Easy bruising and bleeding (the lack of healthy red blood cells prevent the blood from coagulating properly)
- Enlarged spleen
- Unexplained severe bleeding (due to low platelet count)
- Young girls and women may experience extremely heavy menstrual flows due to the abnormal red blood cell production and coagulation
Acute Promyelocytic Leukemia Diagnosis & Treatment
APL is usually diagnosed through a bone marrow aspiration or biopsy. A sample of bone marrow is collected by inserting a long thin needle into the hipbone or breastbone and examining it under a microscope to detect malignant cells.
Many APL patients are treated with a procedure called all-trans-retinoic acid (ATRA), a form of differentiation therapy that causes the promyelocytes to mature and prevents them from multiplying. ATRA is often used in conjunction with chemotherapy to kill the malignant cells. This combination has found to treat APL very effectively—much more than chemotherapy treatment alone.
The medication arsenic trioxide is often prescribed to patients whose APL has returned or whose chemotherapy/ATRA treatments were ineffective.
Bone marrow or stem cell transplants have also found to be the most effective form of treatment, particularly for patients who have relapsed.
Acute Promyelocytic Leukemia Outlook
A patient’s prognosis depends on their overall health and particularly the white blood cell count at the time of diagnosis. Over 90% of patients newly-diagnosed with APL can expect to make a full recovery. Patients who successfully treat the disease must undergo extensive long-term follow-up care to prevent against a potential recurrence.