How do I know if my child has leukemia?

Childhood leukemia, the most common type of cancer in children and adolescents, affects blood cells such as white blood cells that help fight infection. The disease develops in the bone marrow, which is the soft, spongy center of the bones and where blood cells are produced. Abnormal or defective cells, usually immature white blood cells, form there and travel through the bloodstream to other parts of the body. Normally, the body can regulate cell production by sending signals about when to stop producing more; however, leukemia cells do not respond to these signals and continue to reproduce, crowding out and hindering the formation of normal blood cells in the bone marrow.

Although the cause of childhood leukemia in most patients is unknown, scientists state that cancer may be caused by certain DNA changes (mutations) within normal bone marrow cells. Because of the mutation, or coding error, they start to grow out of control and become leukemia cells: genes that help cells grow, divide or stay alive are called oncogenes. While genes that keep cell division under control or cause cells to die at the right time are called tumor suppressor genes.

Researchers are focusing their work on understanding these mutations. Meanwhile, it is relevant to note that the immune system plays a crucial role in protecting the body against disease: a failure could increase the risk of developing leukemia, as acquiring a virus or infection, exposure to toxins in the environment, or to chemicals can weaken the system.

There are different types of leukemia based on the time it takes for the disease to progress (acute or chronic) and the type of white blood cell involved (lymphocyte or myelocyte). Children and young adults with leukemia have a better chance of beating the disease when they receive an accurate diagnosis and begin treatment as early as possible.

However, the question arises: can leukemia in children be found early? Currently, there are no blood tests or other screening tests to find leukemia before symptoms become evident. Signs vary; indeed, many of the early symptoms of leukemia in children are signs of common, less serious childhood illnesses.

Thus, common signs and symptoms of leukemia may include: persistent fatigue and feeling tired, fevers or chills, loss of weight or appetite, the appearance of small red spots under the skin (known as petechiae), lack of appetite, headaches, and frequent infections. 

However, children with leukemia have elevated white blood cell counts and most of these cells do not function properly; because white blood cells help protect the body from infection, recurrent or persistent infections may indicate that a child does not have enough healthy white blood cells.

When faced with these signs, it is necessary to see a health professional, who will determine the best tool to diagnose the disease: through a physical examination, review of the medical history, blood tests such as a complete blood count; bone marrow tests (bone marrow aspiration or biopsy), and tests to look for genetic and chromosomal changes.  

It is important to note that physicians can now successfully treat cases of childhood leukemia. Treatment methods are advancing and survival rates for some forms of the disease continue to improve.