Leukemia - Acute Lymphoblastic - ALL - Childhood: Classification

Approved by the Cancer.Net Editorial Board, 03/2020

ON THIS PAGE: You will learn about the factors that doctors use to describe this type of cancer. This is called classification. Use the menu on the side of your screen.

There is no staging system for childhood ALL, unlike other types of cancer. However, there are a number of factors that help doctors choose the best treatment plan and predict the chance that the disease will come back after treatment. Doctors plan the child’s treatment based on these and other factors:

  • Age. Infants younger than 12 months and children age 10 and older need more intensive treatments.

  • White blood cell counts. Children with very high white blood cell counts need more intensive treatments. Commonly, white blood cell counts are labeled as very high if they are more than 50,000 per microliter (microL). 

  • Immunophenotyping. This test shows the types and amounts of proteins made or expressed by the leukemia cells. Knowing if the cancer cells express the proteins more like those of normal white blood cells called B-cells or T-cells will help doctors plan appropriate treatment. It is also useful to help predict how well treatment will work.

  • Genetic abnormalities in the leukemia cells. Abnormal numbers of chromosomes, abnormal structural changes in a chromosome, or certain molecular genetic changes in the chromosomes of leukemia cells may affect outcome and treatment. It is important to note that the genetic changes referred to here are changes in the genes of the leukemia cells, not all the cells in a child’s body – most children with leukemia have completely normal genes. Learn more about different types of genetic changes in a separate article on this website. 

  • Response to early treatment. How well treatment works in the first 1 to 4 weeks of treatment may predict the leukemia’s overall response to treatment. This will be determined by examining the child’s blood or bone marrow regularly. Recent studies have shown that some children may need more intense treatment to improve the chance of a cure. This includes children whose cancer is not responding well to the first treatments or those who have high levels of residual leukemia cells (cells remaining after treatment) at the end of the treatment period called remission induction (see Types of Treatment).

Information about the cancer’s classification will help the doctor recommend a specific treatment plan. The next section in this guide is Types of Treatment. You may use the menu to choose a different section to read in this guide.