Scientists have found that these cancers are associated with a number of risk factors, but their exact cause in most cases is not yet known. But researchers think these risk factors probably affect the DNA, the genetic material present in the cells lining the nasal passages and paranasal sinuses.

Researchers have made great progress in understanding how certain changes in a person's DNA can cause cells to become cancerous. DNA is the molecule that carries the instructions for nearly everything our cells do. We usually look like our parents because they are the source of our DNA. However, DNA affects more than our outward appearance. It also determines our risk for developing certain diseases, such as some kinds of cancer.

Some genes (parts of our DNA) contain instructions for controlling when our cells grow and divide. Genes that promote cell division are called oncogenes. Others that slow down cell division or cause cells to die at the appropriate time are called tumor suppressor genes. Cancers can be caused by DNA mutations (defects) that turn on oncogenes or turn off tumor suppressor genes.

Some people with cancer have DNA mutations they inherited from a parent, which increase their risk for the disease. But usually DNA mutations occur during life rather than having been inherited. These acquired mutations may result from events such as exposure to radiation or cancer-causing chemicals. Sometimes they occur for no apparent reason.

So far no specific gene changes have been found in these cancers.

Last Medical Review: 08/13/2009
Last Revised: 08/13/2009