Leukemia

Signs and Symptoms

Two general categories of leukemia are acute and chronic. In acute leukemia, symptoms appear quickly and worsen quickly. This form of leukemia may develop over a short period of days to weeks. Abnormal white blood cells may collect in the brain or spinal cord. The result may be headaches, vomiting, confusion, loss of muscle control and difficulty seeing. Some patients develop sores in the eyes or unusual skin rashes. Leukemia also can affect the lungs and other parts of the body.

In chronic leukemia, symptoms may not appear for months or years. Doctors may find chronic leukemia during a routine exam before any symptoms arise. This form of leukemia may develop over longer periods covering months or years before symptoms are apparent. When symptoms do appear, they tend to be mild and worsen gradually. Abnormal white blood cells may gradually collect in various parts of the body, affecting areas such as the skin, central nervous system, digestive tract, kidneys and testicles.

The two primary types of childhood leukemia are acute lymphocytic leukemia (ALL) and acute myelogenous leukemia (AML). These two acute forms of leukemia can develop over a short period of days to weeks. A third chronic form, chronic myelogenous leukemia (CML), is rare among children.

• Acute Lymphocytic Leukemia (ALL) — Acute lymphocytic leukemia — also called lymphoblastic or lymphoid leukemia — accounts for about 75 percent to 80 percent of childhood leukemia. In this form of the disease, the lymphocyte cells, which normally fight infection, are affected. When acute lymphocytic leukemia occurs, the bone marrow makes too many lymphocyte cells that do not mature correctly. The lymphocyte cells overproduce, crowding out other blood cells. Immature blood cells or blasts don't work properly to fight infection. Chromosome abnormalities, or extra chromosomes and structural changes in the chromosome material, are present in the majority of ALL patients.

• Acute Myelogenous Leukemia (AML) — Acute myelogenous leukemia — also called granulocytic, myelocytic, myeloblastic or myeloid leukemia — accounts for about 20 percent of childhood leukemias. Acute myelogenous leukemia is a cancer of the blood in which too many granulocytes, a type of white blood cell that normally fights infection, are produced in the marrow and they don't mature correctly. The immature blood cells or blasts don't work properly to fight infection. The excessive number of these abnormal cells crowd out other healthy blood cells. Children with certain genetic syndromes, including Fanconi anemia, Bloom syndrome, Kostmann syndrome and Down syndrome, have a higher risk of developing AML.

• Chronic Myelogenous Leukemia (CML) — Chronic myelogenous leukemia is the more slowly developing form of myelogenous leukemia and is rare among children. It may develop over a period of months or years. Children with CML have a chromosome rearrangement. Part of chromosome No. 9 breaks off and attaches itself to chromosome No. 22, creating an exchange of genetic material. This rearrangement changes the position and function of certain genes, causing uncontrolled cell growth. Other chromosome abnormalities also can occur.

Like all blood cells, leukemia cells travel throughout the body. Depending on the number of abnormal cells and where these cells collect, patients with leukemia may have a number of symptoms.

Here are some general leukemia symptoms:

• Anemia — Children with leukemia often have fewer than normal healthy red blood cells and platelets. They lack enough red blood cells to carry oxygen through the body, which causes a condition called anemia. Children with anemia may look pale, feel weak and tired and bleed and bruise easily.

• Recurrent Infections — Although children with leukemia may have a high number of white blood cells, these white blood cells are immature and don't fight infection. Children may experience repetitive viral or bacterial infections. They often have symptoms of infection such as fever, runny nose and cough.

• Bone and Joint Pain — Pain in bones and joints is another common symptom of leukemia. This pain is usually a result of the bone marrow being overcrowded and "full."

• Abdominal Distress — Abdominal pain also may be a symptom. Leukemia cells can collect in the kidney, liver and spleen, causing enlargement of these organs. Pain in the abdomen may cause a loss of appetite and weight.

• Swollen Lymph Nodes — Lymph nodes under the arms, in the groin, chest and neck may become swollen when leukemia cells collect in the nodes. Lymph nodes filter the blood.

• Difficulty Breathing or Dyspnea — With T-cell acute lymphocytic leukemia, leukemia cells tend to clump together around the thymus gland. This mass of cells present in the middle of the chest can cause pain and difficulty breathing. Wheezing, coughing or painful breathing requires immediate medical attention.

Diagnosis

Understanding how certain diagnostic procedures are performed and why they are necessary may help you support and prepare your child for these tests.

Blood tests

Blood tests are done frequently to monitor the possible side effects of chemotherapy and radiation therapy. Because the results can influence treatment decisions, these tests often are done before treatment. Depending on the types of blood tests done, blood samples may be obtained by a small needle prick or finger stick on the inside tip of the finger or by inserting a needle into a vein, a procedure called a venipuncture. If a venipuncture is done, remember to apply EMLA cream, an anesthetic, to the puncture site one to two hours before the test. Ask your nurse to show you where and how to apply the cream. If your child has an external catheter, you will learn to draw blood samples at home to deliver to the lab.

Cultures

If your child has a fever or other signs of infection, one or more samples of blood, urine or stool, throat secretion or pus may be taken to check for infection. To confirm an infection, any organisms contained in these samples are allowed to grow in a culture for several days. To get a head start at fighting the infection, however, antibiotics may be prescribed before your child's doctor has the final results of the culture.

If a specific organism is identified, antibiotics may be changed for more effective treatment. Often a specific organism is never identified, in which case "broad-spectrum" antibiotic — effective against more than one organism — may be continued, depending on your child's condition.

Bone Marrow Biopsy

Understandably, bone marrow aspirations may be frightening to you and your child. But a local anesthetic is injected deep under the skin to numb the puncture site and takes effect quickly, helping to control the pain. Whenever possible, we give you the choice of having the procedure performed under general anesthesia.

Spinal Tap

A clear fluid called cerebrospinal fluid (CSF) surround the brain and spinal cord. Sometimes a sample of this fluid is removed and examined for cancer cells or signs of infection. Another name for a spinal tap is lumbar (lower spine) puncture or LP. This procedure takes about 15 minutes.

Bone Scan, Gallium Scan, MIBG

Evaluation and treatment of a child with cancer may involve specialized nuclear medicine scans of organs, tissues or bones to check for disease or infection. The three most common types of scans are bone scans, gallium scans and MIBG scans. MIBG stands for meta-iodobenzylguanidine. Both gallium and MIBG are radioactive substances that enable doctors to detect cancerous cells in the scans.

A nuclear medicine scan requires the injection of a small amount of a radioactive substance into the blood about two to three hours before a bone scan, 48 to 72 hours before the gallium scan and 24 hours before the MIBG scan. Registration and the injection of the radioactive substance should take no more than 15 minutes.

If your child does not have an external central catheter, remember to apply EMLA cream, a topical anesthetic, to the injection site one to two hours before the procedure. Ask your nurse to show you where and how to apply the cream.

Computerized Tomography (CT) Scan

Computerized tomography (CT) scans use computers and X-rays to create pictures with more detail than conventional X-rays. X-rays are sent through the body in thin cross sections to create images. These scans often supplement other diagnostic X-rays.

Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) uses magnets, rather than X-rays, to produce detailed images of the body. An MRI machine sends radio waves into the body and then measures the response with a computer. The computer makes an image or picture of the body's internal organs. MRIs are used for certain types tumors in certain locations of the body because they can produce a better image than X-rays.

Echocardiogram

Because certain types of chemotherapy can affect heart muscle, tests may be done periodically to detect changes in your child's heart to help identify problems before they become serious. An echocardiogram is used to record the echoes of sounds sent through the heart. This test shows the size of the four heart chambers, as well as how the heart muscle functions. Your child may need to remove clothing above the waist for this test.

Ultrasound

An ultrasound exam or sonogram uses high frequency sound waves to create images of organs in the body. No radiation is used. Sound waves bounce off tissue using the same principles as sonar. The echoes that return to a transducter are used to draw the images on the screen.

Treatment

The four types of treatment that your child may undergo are chemotherapy, radiation therapy, bone marrow transplant and biological therapy.

Chemotherapy

Chemotherapy involves drugs to kill cancer cells. These drugs may be taken orally or may be injected into by a needle into a vein or muscle. This type of therapy is called a systemic treatment because the drug enters the bloodstream, travels through the body and can kill cancer cells throughout the body. For acute lymphocytic leukemia (ALL), chemotherapy drugs may be injected through the spine into the fluid that surrounds the brain and spinal cord. This is known as intrathecal chemotherapy.

Radiation Therapy

Radiation therapy uses X-rays or other high-energy rays to kill cancer cells and shrink tumors. Radiation for acute lymphocytic leukemia (ALL) usually comes from a machine outside the body, called external beam radiation therapy.

Bone Marrow Transplant

Bone marrow transplant (BMT) is a newer treatment for this condition. The first step of the treatment involves high doses of chemotherapy - sometimes with radiation -- to destroy all of your child's bone marrow. Healthy marrow from a donor, whose tissue is the same as or almost the same as your child's, is transplanted into your child. The donor may be a twin, who is the best match; a brother or sister; or other person not related. The healthy marrow from a donor is given to your child intravenously through a needle in a vein to replace the marrow that was destroyed. This process, involving marrow from a donor, is called an allogeneic bone marrow transplant.

Another type of bone marrow transplant, called an autologous transplant, is being studied in clinical trials. This procedure involves transplanting your child's own bone marrow. The marrow is taken from your child and treated with drugs to kill cancer cells. The marrow is frozen and saved. Your child then is given a high-dose chemotherapy - sometimes with radiation -- to destroy all of your child's bone marrow. The frozen marrow that was saved is thawed and transplanted back into your child, injected intravenously through a needle in a vein. For the most part, autologous bone marrow transplants have not been effective in treating acute myelogenous leukemia.

To learn more, visit the section on specific BMT treatment options for leukemia.

Biological Therapy

Biological therapy attempts to stimulate or restore the ability of your child's immune system to fight cancer. It uses substances produced by your child's body — or made in a laboratory — to boost, direct or restore the natural defenses against disease. Biological therapy is sometimes called biological response modifier therapy or immunotherapy.