Children’s Cancer Awareness (ACCO.org) · American Cancer Society · Emmanuel Cancer Foundation · SaintJude.org · Donate
If your child does develop cancer, it’s important to know that it’s extremely unlikely there is anything you or your child could have done to prevent it.
A few environmental factors, such as radiation exposure, have been linked with some types of childhood cancers. Some studies have also suggested that some parental exposures (such as smoking) might increase a child’s risk of certain cancers, but more studies are needed to explore these possible links. So far, most childhood cancers have not been shown to have environmental causes.
In recent years, scientists have begun to understand how certain changes in the DNA inside our cells can cause them to become cancer cells. DNA is the chemical that makes up our genes, which control nearly everything our cells do. We usually look like our parents because they are the source of our DNA. But DNA affects more than just how we look. It also influences our risks for developing certain diseases, including some kinds of cancer.
Some genes control when our cells grow, divide into new cells, and die. Genes that help cells grow, divide, or stay alive are called oncogenes. Genes that slow down cell division, repair mistakes in a cell’s DNA, or cause cells to die at the right time are called tumor suppressor genes.
Some children inherit DNA changes (mutations) from a parent that increase their risk of certain types of cancer. These changes are present in every cell of the child’s body, and they can often be tested for in the DNA of blood cells or other body cells. Some of these DNA changes are linked only with an increased risk of cancer, while others can cause syndromes that also include other health or developmental problems.
But most childhood cancers are not caused by inherited DNA changes. They are the result of DNA changes that happen early in the child’s life, sometimes even before birth. Every time a cell divides into 2 new cells, it must copy its DNA. This process isn’t perfect, and errors sometimes occur, especially when the cells are growing quickly. This kind of gene mutation can happen at any time in life and is called an acquired mutation. Acquired mutations are only in the person’s cancer cells and will not be passed on to their children.
Unlike many cancers of adults, lifestyle-related risk factors (such as smoking) don’t play much of a role in a child’s risk of getting cancer. A few environmental factors, such as radiation exposure, have been linked with an increased risk of some childhood cancers. But in some cases exposure to radiation might be unavoidable, such as if the child needs radiation therapy to treat another cancer.