Leukemia Causes, Symptoms, Diagnosis, and Treatments

What Is Leukemia?

Leukemia is cancer of the blood, specifically the white blood cells.

Your body makes blood in your bone marrow. Bone marrow is the soft, spongy center of certain bones.

There are 3 main types of blood cells:

White blood cells.
Red blood cells.
Platelets.

What Causes Childhood Leukemia?

Except for certain genetic syndromes, we don't know what causes childhood leukemia.

Most childhood leukemias are what doctors call acquired diseases. This means that gene changes and chromosome abnormalities in cells occur by chance.

The immune system helps protect the body from disease — and this may include cancer.

Exposure to certain viruses, chemicals, infections, and environmental factors can damage the immune system. A defect in the immune system may increase the risk of getting leukemia.

How common is childhood leukemia?

Leukemia is the most common form of childhood cancer.

It affects about 4,000 kids each year in the U.S., and accounts for about 25% of childhood cancers.

What Are the Types of Leukemia?

There are 3 main types of childhood leukemia:

ALL — also called lymphoblastic or lymphoid leukemia — often affects children between the ages of 2 and 3. ALL accounts for about 75% of childhood leukemia cases each year in the U.S.

ALL affects the lymphocyte cell line, which fights infection.

In ALL, the bone marrow makes too many lymphocytes. They do not mature or function correctly. The immature lymphocytes then overproduce and crowd out the healthy blood cells.

ALL can occur over a short time span of days to weeks.

Most children with ALL have extra chromosomes and changes in the structure of chromosome material.

AML — also called granulocytic, myelocytic, myeloblastic, or myeloid leukemia — accounts for about 19% of childhood leukemias.

AML tends to occur by age 2, and isn't often seen in older children until the teen years. AML is the most common type of acute leukemia in adults.

With AML, the bone marrow makes too many granulocytes, a type of white blood cell that fights infection. They do not mature or function correctly. The immature granulocytes then overproduce and crowd out the healthy blood cells.

AML can occur over a short time span of days to weeks.

Children with certain genetic syndromes have a higher risk of getting AML, including:

Bloom syndrome.
Down syndrome.
Fanconi anemia.
Kostmann syndrome.

CML isn't common in kids.

Like with AML, CML is when the bone marrow makes too many granulocytes. They don't mature or function correctly. The immature granulocytes then overproduce and crowd out the healthy blood cells.

In people with CML, part of chromosome 9 breaks off and attaches to chromosome 22, and they exchange genetic material. This changes the position and functions of certain genes, which results in uncontrolled cell growth.

There may be other chromosome abnormalities, too.

CML can occur over months or years.

What's the difference between lymphocytic and myelogenous leukemia?

Lymphocytic and myelogenous leukemia differ by the stage of development on the pluripotent stem cell. This is the first stage of all blood cells (white blood cells, red blood cells, and platelets). This stem cell goes through stages until it matures into a functioning cell.

We learn the type of leukemia by where the cell is in the stage of development when it becomes cancerous.

The stem cell matures into either the lymphoid or myeloid cells.

The lymphoid cells mature into either B-lymphocytes or T-lymphocytes.

If the leukemia is among these cells, it's ALL. If we find the leukemia even further along this stage, we can classify it as B-cell ALL or T-cell ALL. The more mature the cell, the tougher it is to treat.

The myeloid cells form into platelets, red blood cells, and specialized white blood cells (neutrophils and macrophages).

There are many classes of AML.

What Are the Symptoms of Leukemia?

Because leukemia is cancer of the bone marrow, early symptoms often relate to irregular bone marrow function.

The bone marrow stores and makes about 95% of the body's blood cells.

With leukemia, abnormal white blood cells (blasts) reproduce very quickly. They crowd out and compete for nutrients and space with healthy cells.

While each child's symptoms may differ, the most common symptoms of leukemia are:

Anemia. This happens when bone marrow can't make red blood cells because of crowding. A child may appear tired and pale, and breathe faster. A blood count will show a below normal number of red blood cells.
Bleeding and/or bruising. When marrow can't make platelets due to crowding, a child may bruise more easily. You may also notice tiny red dots on their skin. These very small blood vessels (petechia) leak or bleed. The number of platelets on a blood count will be below normal.
Repeat infections. A blood count showing a high number of white blood cells with leukemia are immature and can't fight infection. A child may have frequent repeat viral or bacterial infections and symptoms like a fever, runny nose, and cough.
Bone and joint pain. This pain is often from the bone marrow crowding.
Abdominal distress. Leukemia cells can collect in the kidney, liver, and spleen, causing these organs to enlarge. A child may lose their appetite and weight.
Swollen lymph nodes. Leukemia cells may collect in lymph nodes under the child's arms and in the groin, chest, and neck, causing swelling.
Trouble breathing. With T-cell ALL, leukemia cells tend to clump together around the thymus gland. This mass of cells in the middle of the chest can cause pain and trouble breathing. Call your child's doctor right away if they have wheezing, coughing, and/or painful breathing.

With acute leukemia (ALL or AML), these symptoms may come on fast, in a matter of days or weeks. With chronic leukemia (CML), symptoms may start slowly, over months to years.

Leukemia symptoms may mimic other blood disorders or health problems. Always consult your child's doctor for a diagnosis.

How Do Doctors Diagnose Childhood Leukemia?

To diagnose leukemia, your child's doctor will take their complete health history and do a physical exam.

They may also order:

Bone marrow aspiration and/or biopsy.
Completeblood count (CBC), to measure the size, number, and maturity of blood cells in a certain volume of blood.
Blood tests, which may include blood chemistries, a check of liver and kidney functions, and genetic studies.
CT scan.
MRI.
X-ray.
Ultrasound.
Lymph node biopsy, to sample and study lymph node tissue under a microscope.
Spinal tap.

How Do Doctors Treat Leukemia?

Your child's doctor will base your child's leukemia treatment on:

Their age, overall health, and health history.
The extent of the disease.
How they do with certain medicines, techniques, or treatments.
Your input.

To start treatment, we often address the symptoms first, such as anemia, bleeding, and infection.

Treatment for leukemia may also include one or a mix of the following:

Chemotherapy.
Intrathecal medicines/chemo (inserted through a needle into the spinal cord and the subarachnoid space).
Radiation therapy.
Bone marrow or peripheral blood stem cell transplant.
Biologic therapy.
Drugs to prevent or treat damage to other systems of the body from leukemia treatment.
Medicines for nausea and treatment side effects and to prevent or treat infections.
Blood transfusions (red blood cells, platelets).
Follow-up care to learn how your child responds to treatment, detect if the disease recurs, and manage late treatment effects.

Stages of Leukemia Treatment

The treatment stages of childhood leukemia include:

Induction. A mix of chemo and/or radiation and medicines to stop bone marrow from making abnormal cells. The goal is remission, when the marrow stops making leukemia cells. This phase may last about a month and repeat if we don't achieve remission.
Intensification. Even when leukemia cells aren't seen in a blood test or bone marrow exam, treatment continues. Cells may still be in the body.
Maintenance. To maintain leukemia-free bone marrow, your child will have less intense chemo for months or years. Routine doctor visits will confirm their response to treatment, detect if the disease recurs, and manage treatment side effects.

Even with aggressive treatment, a child can relapse at any stage of care or months or years later.

When this happens, the bone marrow starts making abnormal cells again.

Long-Term Outlook for Kids With Leukemia

The prognosis for a child with leukemia greatly depends on:

The extent of the disease.
How well the disease responds to treatment.
Genetics.
Age and overall health of your child.
How your child does with certain medicines, procedures, or treatments.
Advancements in childhood leukemia treatment.

As with any cancer, long-term outlook and survival can vary greatly from child to child.

Prompt health care and aggressive therapy are vital for the best outlook. Routine follow-up care is crucial if your child has leukemia.

Side effects of radiation and chemo, and getting cancer a second time, can occur. Experts are always seeking new ways to improve treatment and decrease side effects.

Why Choose UPMC Children's Hospital of Pittsburgh for Leukemia Care?

Our combined team includes world-renowned experts in children's cancer, blood disorders, and diagnostic and interventional radiology. We also work with experts in pathology, nursing, physical and occupational therapy, and psychosocial services, among others.

Your child will have a unique treatment planbased on their age, development, and type of leukemia. We offer a full spectrum of cutting-edge treatment options, including chemo, radiation, and bone marrow transplants.

Your child will have access to cutting-edge research. Doctor-researchers at UPMC Children's Hospital focus on understanding childhood leukemia. That way, we can create better ways to target this cancer.

We're also a member of the Children's Oncology Group (COG) — the world's largest group devoted to childhood cancer research. This allows us to enter children in nearly 100 active studies of the newest cancer treatments with the most promise.

Contact Us About Leukemia Care for Your Child

To learn more about treatment for leukemia at UPMC Children's, call 724-386-6319.