What Is Acute Lymphoblastic Leukemia?
Acute lymphoblastic leukemia (ALL) is a type of blood cancer that starts in white blood cells in your bone marrow, the soft inner part of your bones. It develops from immature lymphocytes, a kind of white blood cell that’s key to your immune system.
ALL is also known as acute lymphocytic leukemia or acute lymphoid leukemia. ”Acute” means it gets worse quickly. It’s a rare type of leukemia, or blood cancer, in adults but the most common type in children.
Acute Lymphoblastic Leukemia Causes and Risk Factors
Doctors don’t know what causes most cases of ALL. But research has found that certain things might raise your risk, including:
- Contact with high levels of radiation to treat other types of cancer
- Contact with chemicals such as benzene, a solvent used in oil refineries and other industries and found in cigarette smoke; and some cleaning products, detergents, and paint strippers
- Infection with the human T-cell lymphoma/leukemia virus-1 (HTLV-1) or the Epstein-Barr virus (EBV), mostly outside the U.S.
- Having a medical condition that’s tied to your genes, such as Down syndrome
- Being white
- Being male
Acute Lymphoblastic Leukemia Symptoms
Some symptoms of ALL can be vague. They include:
- Loss of appetite or weight loss
- Night sweats
- Tiny red spots just under your skin (petechiae)
- Stomach pain
Many of the symptoms happen because your body is reacting to a lack of healthy blood cells. Leukemia cells can crowd them out in your bone marrow.
A lack of red blood cells may cause symptoms of anemia, including:
- Fatigue or weakness
- Dizziness or light-headedness
- Feeling cold
- Shortness of breath
Without enough healthy white blood cells, you may have:
- More infections than usual
A lack of platelets, tiny cells that help your blood clot, may cause:
- Lots of bruising for no clear reason
- Frequent or severe nosebleeds, bleeding gums, or other unusual bleeding, such as from minor cuts
Depending on where the leukemia cells are, you might also have:
- A full or swollen belly from cancer cells in your liver or spleen
- Enlarged lymph nodes such as in your neck or groin, under your arms, or above your collarbone
- Bone or joint pain
- Headache, trouble with balance, vomiting, seizures, or blurred vision if the cancer has spread to your brain
- Trouble breathing if it’s spread to your chest
Acute Lymphoblastic Leukemia Diagnosis
If your doctor suspects leukemia, they may do tests, including:
- Blood tests. A complete blood count (CBC) shows how many of each type of blood cell you have. A peripheral blood smear checks for changes in how your blood cells look.
- Bone marrow tests. Your doctor will put a needle into a bone in your chest or hip and take out a sample of bone marrow. A specialist will look at it under a microscope for signs of leukemia.
- Imaging tests. X-rays, CT scans, or ultrasounds can tell your doctor whether the cancer has spread.
- Spinal tap. This is also known as a lumbar puncture. Your doctor will use a needle to take a sample of fluid from around your spinal cord. A specialist can look at it to see if the cancer has reached your brain or spinal cord.
Your doctor might also test your blood or bone marrow for changes in your chromosomes or look for markers on cancer cells. The results will tell them more about the type of leukemia you have and help them plan your treatment.
Acute Lymphoblastic Leukemia Treatment Stages
Most cancers are divided into stages, based on how far they’ve spread. But with ALL, doctors describe it according to treatment.
- Untreated. This is a new diagnosis. You might have been treated for symptoms but not for the cancer itself.
- Remission. You’ve had treatment to kill as many leukemia cells as possible. Your CBC is normal, and no more than 5% of cells in your bone marrow are leukemia cells.
- Recurrent. This is cancer that’s come back after treatment and remission.
Acute Lymphoblastic Leukemia Treatment
Treatment happens in two parts: induction therapy, to put you in remission, and post-remission therapy.
You may have more than one type of treatment. These include:
- Chemotherapy. You might take a mix of drugs that kill or slow cancer cells, usually over a couple of years.
- Targeted therapy. Some drugs target specific parts of cancer cells and tend to have fewer or milder side effects than chemotherapy. They include dasatinib (Sprycel), imatinib (Gleevec), nilotinib (Tasigna), and ponatinib (Iclusig).
- Radiation therapy. Your doctor might use high-energy radiation to kill cancer cells if they’ve reached your brain or bone or before you have a stem cell transplant.
- Immunotherapy. These drugs boost your immune system to kill or slow the growth of cancer cells. They include blinatumomab (Blincyto) and inotuzumab ozogamicin (Besponsa).
- A stem cell transplant. After high doses of chemotherapy and possibly radiation, you get stem cells that will grow into healthy blood cells. They might be your own or come from a donor. If you can’t handle high doses of chemotherapy and radiation, you might get lower doses with a "mini-transplant."
About 80% to 90% of adults reach remission after treatment. For about 30% to 40%, the cancer doesn’t return. But many relapse, meaning the disease returns.
You’ll need post-remission therapy to keep the cancer from coming back. This involves cycles of treatment over 2 to 3 years. It aims to rid your body of leukemia cells.
The FDA has also approved a form of treatment called CAR T-cell therapy. It uses some of your own immune cells, called T cells, to treat your cancer. Doctors take the cells out of your blood and add genes to them. The new T cells are better able to find and kill cancer cells.
The drug, tisagenlecleucel (Kymriah), is approved only for children and young adults up to age 25 who have a certain type of ALL and haven’t gotten better with other treatments. But scientists are working on a version of CAR T-cell therapy for adults and for other kinds of cancer.
You might also consider joining a clinical trial to test new treatments that aren’t widely available. Talk to your doctor about which one would be the best fit for you and about what to expect.
Acute Lymphoblastic Leukemia Prognosis
The outlook for acute lymphoblastic leukemia depends on several things, including:
- Your age. Younger patients tend to do better.
- Your lab test results. The prognosis is better if you have a lower white blood count when you're diagnosed.
- Your chromosomes. People who don’t have a problem in their genes called the Philadelphia chromosome usually do better.
- Your response to chemotherapy. The prognosis is better if you have no evidence of leukemia 4 to 5 weeks after starting treatment.
You’ll need follow-up tests for several years after treatment to check your overall health and be sure the cancer doesn’t come back.
It’s natural to feel worried when you’ve been diagnosed with cancer. Reach out to loved ones, religious groups, counselors, or support groups for help and support.