Risk Factors and Causes of Cancers in Adolescents

A risk factor is anything that affects a person's chance of getting a disease such as cancer. Different cancers have different risk factors.

In older adults, many cancers are linked to lifestyle-related risk factors such as smoking, being overweight, eating an unhealthy diet, not getting enough exercise, and drinking too much alcohol. Exposures to things in the environment, such as radon, air pollution, asbestos or radiation during medical tests or procedures, also play a role in some adult cancers. These types of risk factors usually take many years to influence cancer risk, so they are not thought to play much of a role in cancers in children or teens.

Cancer occurs as a result of changes (mutations) in the genes inside our cells. Genes, which are made of DNA, control nearly everything our cells do. Some genes affect when our cells grow, divide into new cells, and die. Changes in these genes can cause cells to grow out of control.

Some people inherit gene mutations from a parent that increase their risk of certain cancers. In people who inherit such a mutation, this can sometimes lead to cancer earlier in life than would normally be expected. But most cancers are not caused by inherited gene changes.

The causes of gene changes in certain adult cancers are sometimes known (such as the lifestyle-related and environmental risk factors mentioned above), but the reasons for gene changes that cause most cancers in children and teens are not known. Many are likely to just be random events that sometimes happen inside a cell, without having an outside cause.

Still, there are some known causes of cancer in teens. For instance:

Still, these and other known risk factors probably account for only a small portion of cancers in teens overall.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: August 15, 2016 Last Revised: September 29, 2016

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