What Is Secondary Acute Myeloid Leukemia?
Secondary acute myeloid leukemia (sAML) is a type of acute myeloid leukemia (AML), a kind of blood cancer that starts in white blood cells that grow in your bone marrow. SAML often affects people who have one of these blood cell diseases:
- Myelodysplastic syndrome (MDS)
- Myeloproliferative disorder (MPD)
- Aplastic anemia
You can also get secondary AML after you have radiation or chemotherapy to treat another kind of cancer.
AML that isn't caused by another blood disease or treatment is called primary AML.
The treatments for these two cancers are slightly different.
You may have a lot of questions about how your cancer started and how to treat it. Your doctor will do their best to answer these questions and find ways to slow or stop your cancer.
Causes and Risk Factors for Secondary Acute Myeloid Leukemia
Early blood cells form in your bone marrow, the soft tissue in the center of your bones, from stem cells. They grow into infection-fighting white blood cells, oxygen-carrying red blood cells, and blood-clotting platelets.
Your DNA holds the instructions that tell these blood cells when to grow and divide. But DNA changes called mutations may change the way blood cells grow. Mutations can make your blood cells divide too quickly and turn into cancer.
When you have AML, your body makes more white blood cells than it needs, but those cells are too abnormal to fight infections. Secondary AML happens when a disease or treatment like chemotherapy changes your DNA or directly affects your blood cells.
Some chemotherapy drugs that treat cancer can raise your risk for AML, including:
Radiation therapy for cancer can also raise your risk for secondary AML. Doctors aren’t sure whether the small amount of radiation exposure you get from imaging tests like CT scans or X-rays might boost your AML risk, but the chances are probably low.
Diseases like MDS, MPD, and aplastic anemia affect your body's production of new blood cells and may lead to AML.
With MDS, the blood-forming cells in your bone marrow are abnormal. In myeloproliferative disorders, your bone marrow makes too many abnormal blood cells. And aplastic anemia keeps your body from making enough new blood cells.
Symptoms of Secondary Acute Myeloid Leukemia
Secondary AML causes the same symptoms as AML. Most symptoms happen when your blood cell counts drop. They depend on the type of blood cell affected.
Symptoms of low red blood cells (anemia):
- Shortness of breath
- Pale skin
Symptoms of a low number of normal white blood cells:
Symptoms of low platelets:
- Bleeding too much
- Heavy periods
Getting a Diagnosis
Be sure your doctor knows if you've had radiation, chemotherapy, or a blood disorder. They’ll also ask about your symptoms and medical history. After doing a physical exam, your doctor might order one or more of these tests:
Blood tests. A complete blood count (CBC) measures the amount of white blood cells, red blood cells, and platelets in your blood. AML can lower the number of normal blood cells.
Other blood tests check how many blood cells you have and what they look like. Most people with AML have too many abnormal white blood cells and not enough red blood cells or platelets.
Your doctor will also look for immature white blood cells, called blasts. They’ll usually diagnose AML if at least 20% of your white blood cells are blasts.
Bone marrow tests. For these tests, your doctor takes a sample of liquid or tissue from your bone marrow so a specialist can look at it in a lab. A bone marrow test is the only way to know for sure if you have secondary AML.
Gene tests. AML cells have DNA changes that may be visible under a microscope. Sometimes, pieces of DNA are in the wrong place or missing. Other gene tests look for DNA changes that are too small to see.
Questions for Your Doctor
Any time you see your doctor, it's helpful to have a list of questions ready. You can also bring a family member or friend to help you remember your questions and write down what your doctor says.
You may want to ask things like:
- Do I need more tests before you recommend a treatment?
- What's my outlook?
- What are my treatment choices?
- How do they work?
- What side effects could those treatments have?
- How will I know if my treatment isn't working?
- When should I call you?
- Should I join a clinical trial?
Treatment for Secondary Acute Myeloid Leukemia
Treatment for secondary AML is often very similar to treatment for primary AML.
Induction. The first part of the treatment is strong chemotherapy to kill as many cancer cells as possible. Often, doctors treat AML with the 7 + 3 regimen. You get the chemo drug cytarabine every day for 7 days, plus anthracycline on the first 3 days of your treatment.
One treatment that's specifically approved for secondary AML is a combination of two chemotherapy drugs, daunorubicin and cytarabine liposome.
You get chemotherapy drugs through a shot or an IV into a vein.
After this, your doctor will do another bone marrow test to check your blood cell counts. If blasts make up less than 5% of the cells in your bone marrow, your doctor will tell you that you're in remission. This means doctors can’t find any more signs of cancer in your body.
Consolidation. This is the next step of treatment once you're in remission. You might get another round of chemo to kill any cancer cells left behind and prevent a relapse.
Or you could have a stem cell transplant. After high-dose chemotherapy, your doctors replace the blood cells that chemo destroyed with healthy cells from a donor or from yourself.
A stem cell transplant is an intense treatment that can have serious complications. But it may give you the best chance of long-term remission or a cure.
Taking Care of Yourself
A cancer diagnosis can sometimes make you feel like your life is out of control. One way to take back control and feel better is to practice good self-care.
- Relax. Get enough sleep at night, and make time for naps during the day if you need them. Take a break to do things that calm your mind and body, like reading or listening to music.
- Eat well. Cancer and its treatments can affect your appetite. Try to eat more foods that are healthy sources of calories and protein, like nuts, beans, whole grains, fruits, and vegetables.
- Go for a walk. You can also ride a bike or swim. Any kind of exercise will help ease stress and keep up your strength.
- Breathe. When you’re feeling overwhelmed, pause and take a deep breath. Practice meditation. Or try listening to your favorite music to help you focus on something pleasant.
What to Expect
It's important to remember that everyone who has AML is different. Many things can affect your outlook, including your age and your genes.
The overall 5 year survival rate for people ages 20 and older with AML is about 30%. This means 30% of those people will most likely live at least 5 or more years beyond diagnosis. The 5-year rate is 69% in people younger than age 20.
Primary AML usually has a better outlook than secondary AML. Chemo often doesn't work as well against the secondary form. But now that a medication is available for secondary AML and other treatments are being studied in clinical trials, your doctor has more options to try.
Cancer treatment can be an emotional time. It's important to reach out to others for help. You can start with friends and family. Also lean on your doctor and the other members of your treatment team if you have questions or concerns, or if you find yourself struggling with side effects.
Leukemia support groups are another place to turn. You'll meet other people with blood cancers who can relate to what you're going through. They may also have advice to help you manage your condition and improve your quality of life. You can find a support group through an organization like the Leukemia & Lymphoma Society.
If your emotions become so intense that they affect your daily life, a counselor or therapist can talk you through them. Therapy can help you cope with your diagnosis so you feel less overwhelmed and alone.