Acute lymphoblastic leukemia, or ALL, is a quickly progressing disease in which too many abnormal white blood cells are found in the bone marrow (the soft, spongy center of long bones). ALL accounts for about 75 to 80 percent of childhood leukemias, and 85 percent of newly diagnosed patients go on to become event-free survivors. In some cases, children who are treated for ALL and achieve an initial complete remission will have the disease return; this is known as relapsed acute lymphoblastic leukemia.
Children and adolescents with acute lymphoblastic leukemia are treated at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center through the Leukemia Program. Continue reading to learn more about ALL or visit the Leukemia Program to learn about our expertise and treatment options for this condition.
Leukemia is the most common form of cancer in children.
It’s important to understand that leukemias most often occur for no known reason and in nearly all cases its cause cannot be determined. There’s nothing that you could have done or avoided doing that would have prevented the disease from developing. In the majority of childhood leukemias, gene mutations and chromosome abnormalities in the leukemia cells occur by chance. The abnormalities found in leukemia cells are not found in the other cells of the body.
In addition to acute lymphoblastic leukemia (ALL), there are two other types of leukemia seen in children:
What’s the difference between ALL, AML and CML?
Acute lymphocytic leukemia (ALL)
Acute myelogenous leukemia
Chronic myelogenous leukemia (CML)
These three types all have different leukemia treatments.
What determines what kind of leukemia my child’s has?
The type of leukemia (lymphoblastic or myelogenous) is determined by the type of marrow cell from which the cancer develops.
What are the types of ALL?
There are two types of lymphocytes normally found in the body:
The blast cells of ALL can arise from B-cell lymphocytes or T-cell lymphocytes. There are two main types of ALL: B-cell ALL and T-cell ALL. B-cell ALL is more common, especially in infants, pre-school- and school-age children. T-cell ALL tends to occur more frequently in older children and teenagers.
Because leukemia is a cancer of the bone marrow, the initial symptoms often are related to abnormal bone marrow function. Bone marrow is responsible for producing the body's blood cells, including the red blood cells, white blood cells and platelets. While your child may experience symptoms differently, some of the most common include:
ALL can cause a variety of symptoms in children based on their age and their disease type. Keep in mind that the symptoms of ALL may resemble other, more common conditions or medical problems. Always consult your child's physician for a diagnosis.
Your child’s physician may order a number of different tests to determine whether your child has ALL and what type of ALL your child has. In addition to a physical examination and history, some of these may include:
After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. Then, we will meet with you and your family to discuss the results and outline the best treatment options for your child's leukemia.
Your child’s physician will determine a specific course of treatment for childhood leukemia based on several factors, including:
Treatment for ALL is a long-term process. Chemotherapy and other treatment for the disease may take two years or more to complete.
There are a number of treatments that your child’s physician may recommend. Some of them help to treat the leukemia, while others are intended to address complications of the disease or side effects of the treatment. Treatment usually begins by addressing your child’s symptoms, such as anemia, bruising and/or fever. In addition, treatment may include the following (alone or in combination):
Chemotherapy is a drug treatment that interferes with the cancer cell's ability to grow or reproduce. For some types of cancer, chemotherapy is used alone, while in others it is used in conjunction with other therapy, such as radiation or surgery. Chemotherapy is the standard first treatment for acute lymphoblastic leukemia (ALL).
How is chemotherapy given to children?
Your child my receive chemotherapy:
Does chemotherapy cause side effects in children?
While chemotherapy can be quite effective in treating certain cancers, the medications don’t distinguish healthy cells from cancer cells. As a result, there can be side effects during treatment. Your child’s care team will work to manage or prevent these side effects whenever possible.
What other treatments are used?
Radiation therapy uses high-energy rays (radiation) from a specialized machine to damage or kill cancer cells and shrink tumors. Radiation is usually only given if your child is at a high risk of relapse occurring in the brain or central nervous system.
Stem cell transplant
A stem cell (or bone marrow) transplant is a treatment that is rarely used to treat ALL except for:
Stem cells are a specific type of cell from which all blood cells develop. They can develop into red blood cells to carry oxygen, white blood cells to fight disease and infection and platelets to aid in blood clotting. Stem cells are found primarily in bone marrow, but some also circulate in the blood stream.
In ALL, the cells for a stem cell transplant come from donors (other people). These donated cells are used to replace your child’s stem cells after particularly intense treatment with chemotherapy and/or radiation.
We may give your child other medications to prevent or treat damage to other systems of his body caused by treatment or its side effects. Your child also may be given antibiotics to prevent or treat infections.
What is sanctuary therapy?
In children with ALL, leukemia cells travel everywhere in the body, including into the brain and spinal fluid. Not all chemotherapy drugs that are given by mouth, vein or in the muscle can get into the brain effectively to treat any leukemia that is “hiding” there.
However, it is important to treat the leukemia cells hiding in the brain and spinal fluid to prevent the leukemia from coming back. To treat the leukemia hiding in the brain and spinal fluid, your child will receive:
Your child may also receive:
What are the phases of leukemia treatment for children?
Your child’s pediatric oncologist will work with pathologists and other specialists to determine your child’s specific type of ALL. Based on the specific diagnosis, your child’s physician will recommend a treatment regimen. In general, stages in the treatment of leukemia include:
1. Remission induction
Remission induction is the first stage of ALL treatment. It consists of chemotherapy given over a four-week period to clear the marrow of visible leukemia cells.
The goal of this phase is to achieve complete remission, which means leukemia cells are no longer visible under a microscope when examining either the bone marrow or blood.
The induction phase usually lasts approximately one month. Most children are in complete remission at the end of the month of treatment. If your child is not in remission after the first month (that is, leukemia cells can still be seen in the marrow under a microscope), another induction phase will be started using different chemotherapy drugs.
Even after remission is achieved, leukemia cells are still present in the body, which is why further therapy is necessary.
2. Intensification or consolidation
Intensification or consolidation is continued treatment with chemotherapy to kill additional leukemia cells.
This phase will include chemotherapy drugs given in the blood, in the vein, in the spinal fluid and sometimes in the muscle.
Radiation therapy also may be given to the brain during this phase.
3. Maintenance or continuation
The goal of this stage is to eradicate all leukemia from the body.
Usually during this phase, less intensive chemotherapy is used, much of which can be given at home.
This phase will last for many months.
Your child must visit his physician regularly during this stage to determine response to treatment, detect any recurrent disease and manage any side effects of treatment.
What is minimal residual disease (MRD)?
Minimal residual disease (MRD) is a term that is used for the “invisible” leukemia that is left behind after your child is in complete remission. It means that leukemia cells are still in your child's body, but there are too few of them to see them under a microscope.
Doctors use special tests after the end of the induction phase to measure the amount of MRD remaining in a patient's marrow.
The results of MRD tests are used to help determine the type of treatment your child’s doctor will recommend during the intensification phase of treatment. Children with higher levels of MRD at the end of induction are often given stronger chemotherapy drugs during the intensification phase to kill the remaining leukemia cells hiding in the body.
What is the long-term outlook and prognosis for a child with leukemia?
The prognosis for children with ALL is very positive. The five-year, event-free survival rate (which refers to survival without relapse) for children with ALL is about 85 percent. Ultimately, more than 90 percent of patients are cured of the disease.
The prognosis (chance of recovery) and treatment options depend on:
As with any cancer, prognosis and long-term survival can vary greatly. Relapse can occur during any stage of treatment, even with aggressive therapy, or may occur months or years after treatment has ended.
Overall, the outcomes of patients with relapsed ALL is poor. In general, relapsed ALL cells become resistant to chemotherapy drugs. Patients who relapse during or just after completing treatment may benefit from a stem cell transplant. Patients who relapse six months or more after initial treatment can often be re-treated with more intensive chemotherapy.
Prompt medical attention and aggressive therapy are important for the best prognosis, and continuous follow-up care is essential. New methods are continually being discovered to improve treatment and decrease side effects of the treatment for the disease.
Childhood cancer was once considered to always be fatal, but today, the majority of children diagnosed with cancer can expect to be long-term survivors.
Survivorship comes with numerous complex issues: the long-term effects of treatment and the risk of second cancers, as well as social and psychological concerns.
Since 1993, physicians, nurses, researchers and psychologists in our cancer survivorship program at David B. Perini, Jr. Quality of Life Clinic at Dana-Farber/Boston Children’s have helped thousands of survivors of pediatric cancers, treated at the institute and at other hospitals in New England and elsewhere, to manage these long-term consequences.
Stephen Sallan, MD describes symptoms, diagnosis and treatment for acute lymphoblastic leukemia (ALL) in children.