Cancer Center

Acute Lymphoblastic Leukemia (ALL) in Children

Here is some information about the types of second opinions we offer and how to request one.

About 80 percent of all childhood leukemia is acute lymphoblastic leukemia (ALL), also called acute lymphocyte or lymphoid leukemia. There are about 3,000 cases of ALL in children and youth up to age 21 each year in the U.S. 

Acute lymphoblastic leukemia in children has one of the highest cure rates and we are specially equipped at The Children's Hospital of Philadelphia to diagnose and effectively treat this type of leukemia and all childhood leukemias.

Through our Pediatric Leukemia and Lymphoma Program in partnership with our Pediatric Blood and Marrow Transplantation Program, we bring together a team of experts in your child's particular type of leukemia, to develop a comprehensive leukemia treatment plan to ensure the best possible outcome.

What is acute lymphoblastic leukemia?

Acute lymphoblastic leukemia in children affects the immature forms of white blood cells called lymphocytes. There are two basic types of lymphocytes, B-lymphocytes and T-lymphocytes, and their immature forms are the source of the two corresponding subsets of ALL, T-ALL and B- or pre-B ALL. The job of lymphocytes is to identify and combat foreign substances, bacteria and viruses in the body. In ALL, the bone marrow makes too many immature lymphocytes (called lymphoblasts) that do not mature correctly. The lymphoblasts overproduce and crowd out normal blood-forming cells. Immature blood cells (blasts) do not have the ability to fight infection.

Learn more about signs and symptoms of pediatric leukemia.
Learn more about how pediatric leukemia is diagnosed and treated.

Promising early results of T cell therapy to treat ALL and other B cell cancers

CTL019, a clinical trial of T cell therapy for patients with B cell cancers such as acute lymphoblastic leukemia, B cell non-Hodgkin lymphoma (NHL), and the adult disease chronic lymphocytic leukemia (CLL), has shown exciting early results for the first patients to be treated.

How CTL019 works

This clinical trial, formerly referred to as CART19, uses immune cells taken from a patient's own blood, called T cells. These cells are genetically modified to express a protein which will recognize and bind to a target called CD19, which is found on cancerous B cells. Here is how CTL019 works:

  1. The cancerous immune cell. B cells, which are found in the immune system, become cancerous in certain leukemias and lymphomas, such as ALL, NHL and CLL.
  2. The healthy immune cell. T cells are the workhorses of the immune system, recognizing and attacking invading disease cells.
  3. The problem. Cancerous B cells fly under the radar of immune surveillance, evading detection by T cells.
  4. The solution. In this experimental treatment, T cells are collected from a patient, then reengineered in a lab to recognize and attach to a protein that is found only on the surface of B cells. After this reengineering, they are called chimeric antigen receptor T cells. The cells are put back into the patient where they disperse to find cancerous B cells.
  5. The result. As the reengineered cells multiply in the body, they attach to and kill the rapidly dividing, cancerous B cells. They remain in the body long after to continue fighting any new cancerous B cells.

Initial results of CTL019

While the numbers of patients treated so far are small — 10 adults with chronic lymphocytic leukemia (CLL), and 2 children with acute lymphoblastic leukemia (ALL) — scientists at The Children’s Hospital of Philadelphia and the University of Pennsylvania have been able to show:

Scientists at The Children’s Hospital of Philadelphia and the University of Pennsylvania are very hopeful that CTL019 could in the future be an effective therapy for patients with B cell cancers. However, because so few patients have been treated, it is critical that more adult and pediatric patients are enrolled in the study to determine whether a larger group of patients with B cell cancers will have the same response.

How to contact us

Review the following options for contacting CHOP about CTL019.

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Acute Lymphoblastic Leukemia: Alex's Story

Born with Down syndrome and a congenital heart defect, this brave little boy was diagnosed with ALL at 27 months old. Read Alex's Story »

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