Acute Lymphocytic Leukemia: Causes and more

Acute lymphocytic leukemia (ALL) is a type of cancer of the blood and bone marrow the spongy tissue inside bones where blood cells are made.

Acute lymphocytic leukemia (ALL) is a cancer of the blood and bone marrow. It affects white blood cells, which your body needs to fight infection. It's the most common type of cancer in children but can also affect adults. Children have a much better chance of recovering from ALL than adults.

The word “acute” in acute lymphocytic leukemia comes from the fact that the disease progresses rapidly and creates immature blood cells, rather than mature ones. The word “lymphocytic” in acute lymphocytic leukemia refers to the white blood cells called lymphocytes, which ALL affect. Acute lymphocytic leukemia is also known as acute lymphoblastic leukemia.

It is the most common type of cancer in children, and treatments result in a good chance for a cure. Acute lymphocytic leukemia can also occur in adults, though the chance of a cure is greatly reduced.

What is acute lymphocytic leukemia (ALL)?

Moreover, acute lymphocytic leukemia (ALL) is a fast-growing blood cancer that forms in immature white blood cells called lymphocytes. It usually starts in the bone marrow (soft, spongy tissue inside bones), which is where white blood cells form.

ALL usually spreads quickly to other areas of the body, such as the spleen, liver, lymph nodes, testicles, brain, and spinal cord.

Are there different types of ALL?

There are two types of lymphocytes: B-cells and T-cells. B-cells make antibodies and help us fight infections. T-cells destroy germs and support other cells in our immune system. ALL can develop either in B-cells or T-cells.

What are the symptoms of acute lymphocytic leukemia (ALL)?

Symptoms of ALL include the following:

Abdominal pain, swelling or fullness.
Anemia.
Bleeding, such as frequent nosebleeds or heavy menstrual periods.
Bruising.
Cough.
Dizziness.
Fatigue.
Fever.
Frequent infections.
Joint pain.
Loss of appetite.
Night sweats.
Pale skin.
Shortness of breath.
Swollen lymph nodes.
Unexplained weight loss.
Weakness.

When to see a doctor

Make an appointment with your doctor or your child’s doctor if you notice any persistent signs and symptoms that concern you.

Many signs and symptoms of acute lymphocytic leukemia mimic those of the flu. However, flu signs and symptoms eventually improve. If signs and symptoms don’t improve as expected, make an appointment with your doctor.

Causes

Acute lymphocytic leukemia occurs when a bone marrow cell develops changes (mutations) in its genetic material or DNA. A cell’s DNA contains the instructions that tell a cell what to do. Normally, the DNA tells the cell to grow at a set rate and to die at a set time. In acute lymphocytic leukemia, the mutations tell the bone marrow cell to continue growing and dividing.

When this happens, blood cell production becomes out of control. The bone marrow produces immature cells that develop into leukemic white blood cells called lymphoblasts. These abnormal cells are unable to function properly, and they can build up and crowd out healthy cells.

It’s not clear what causes the DNA mutations that can lead to acute lymphocytic leukemia.

How is acute lymphocytic leukemia (ALL) diagnosed?

Your healthcare provider evaluates your symptoms, reviews your medical history, and does a physical exam. If they suspect ALL, they'll order a complete blood count (CBC). Someone with ALL usually has:

Your healthcare provider may also do a bone marrow biopsy. They use needles to take samples of bone marrow fluid and a small piece of solid bone, usually from your hip bone. This is a small outpatient procedure usually done under local anesthesia. A pathologist examines the samples in a lab to check for ALL.

Other tests for ALL include:

Chromosome tests usually done in the bone marrow fluids.
Spinal tap (lumbar puncture).
Lymph node biopsy.

Imaging tests like MRIs or CT scans can be used if your healthcare providers think that cancer has spread to other areas of your body. ALL can also cause organs like the liver and spleen to get too big.

How is acute lymphocytic leukemia (ALL) treated?

The most common treatment for ALL is long-term chemotherapy. Chemotherapy (chemo) is the use of drugs to destroy cancer cells. Immunotherapy and targeted therapy can also be combined with chemotherapy to make it more effective. Sometimes a bone marrow transplant follows chemo usually in ALL patients who are at high risk for future relapse. Since ALL doesn't always form tumors, other common cancer treatments such as surgery and radiation therapy aren't as effective.

How does chemotherapy treat ALL?

Chemo for ALL is usually delivered in three phases:

Induction: You receive four to six weeks of intense chemo, usually as an inpatient (staying overnight) in the hospital, with the goal of remission (no signs or symptoms of cancer, though the cancer may still be in your body at lower amounts).
Consolidation (intensification): If you go into remission, you receive several more months of chemo (multiple treatments each week) that gradually get more intense. Most people don't need to stay in the hospital during this phase.
Maintenance (post-consolidation): You receive less intensive chemo for about two years to prevent the cancer from returning.

How does a bone marrow transplant treat ALL?

High doses of chemotherapy can severely damage your bone marrow. So, some people with ALL need a bone marrow transplant to restore the bone marrow so it can produce new blood cells and give you a new immune system. You may receive bone marrow stem cells from a donor (the preferred method, usually a family member or a matched, unrelated donor identified from an international donor registry pool). Or less commonly, your provider may harvest your own stem cells, purify them, and put them back into your bone marrow. This might happen if you can't find a donor with matching DNA. Bone marrow transplant procedures are almost always covered by your insurance if medically necessary.

How does targeted therapy treat acute lymphocytic leukemia (ALL)?

Targeted therapies aim for specific parts of cancer cells. People with ALL caused by an abnormal chromosome (about 25% of adults and a very small number of children) may benefit from this treatment.

How does immunotherapy treat acute lymphocytic leukemia (ALL)?

Immunotherapy helps your body's own immune system attack cancer cells. Immunotherapy may include:

CAR T-cell therapy: CAR T-cell therapy removes immune cells from your body, alters them in a lab and returns them to your body where they can identify and attack leukemia cells. This type of therapy is usually reserved for ALL patients when chemo or combination of chemo and immunotherapy or targeted therapy does not work.
Monoclonal antibodies: Synthetic (man-made) antibodies attack proteins on leukemia cells. They are usually combined with chemo or targeted therapy to make them more effective.

Risk factors

Factors that may increase the risk of acute lymphocytic leukemia include:

Previous cancer treatment. Children and adults who’ve had certain types of chemotherapy and radiation therapy for other kinds of cancer may have an increased risk of developing acute lymphocytic leukemia.
Exposure to radiation. People exposed to very high levels of radiation, such as survivors of a nuclear reactor accident, have an increased risk of developing acute lymphocytic leukemia.
Genetic disorders. Certain genetic disorders, such as Down syndrome, are associated with an increased risk of acute lymphocytic leukemia.

What are the complications of ALL?

If acute lymphocytic leukemia spreads to other organs, such as the brain and spine, it can lead to:

Balance problems.
Blurred vision.
Facial muscle weakness or numbness.
Headaches.
Nausea and vomiting.
Seizures.

A certain type of T-cell ALL affects the thymus, a small gland in the upper front of your chest, near your neck. It can cause the thymus gland to swell, so you may see a bulge under the skin of your chest. If the gland gets too big, it can press on your windpipe and make you cough or make breathing difficult. The thymus can also press on a large vein called the superior vena cava (SVC). This can cause SVC syndrome when blood can’t pass through your vein toward your heart and backs up. This causes swelling of your face and upper extremities.

SVC syndrome is an emergency. Seek immediate medical attention if you experience these symptoms: