What Causes Bone Cancer?

The information here focuses on primary bone cancers (cancers that start in bones) that most often are seen in adults. Information on Osteosarcoma, Ewing Tumors (Ewing sarcomas), and Bone Metastases is covered separately.

There are different types of primary bone cancers (cancers that start in the bones), and while they might have some things in common, these different cancers most likely do not all have the same causes.

Researchers have found some risk factors for bone cancer, but often it’s not clear exactly how these factors might affect how cells in the bones become cancer cells. Research is underway to learn more about the causes of these cancers.

Scientists have learned how certain changes in the DNA in bone cells can cause them to become cancerous. DNA is the chemical in our cells that makes up our genes, which control how our cells function. We usually look like our parents because they are the source of our DNA. But DNA affects more than how we look. It influences our risks for developing certain diseases, including some kinds of cancer.

• Genes that normally help cells grow, divide, or stay alive can sometimes change to become oncogenes.
• Genes that help keep cell division under control, repair mistakes in DNA, or make cells die at the right time are called tumor suppressor genes.

Cancers can be caused by gene mutations (defects) that create oncogenes, or that turn off tumor suppressor genes.

Some people inherit gene mutations (changes) from a parent that increase their risk of bone cancer. (See Risk Factors for Bone Cancer.) Some of these mutations are now known, and genetic testing can look for them.

But the gene changes leading to bone cancer are usually acquired during life rather than inherited from a parent. These changes sometimes result from factors such as exposure to radiation, but most of these changes are probably just random events that sometimes happen inside a cell, without having an outside cause. These mutations are present only in the cancer cells, so they cannot be passed on to the person’s children.

Scientists are making progress in understanding these genetic changes and how they happen, but there are still many things that are not completely understood at this time. As more is learned about these changes, it might help doctors find better ways to prevent, diagnose, and treat these cancers.