Scientists do not know exactly what causes most adrenal cortical tumors. Over the past few years, they have made great progress in understanding how certain changes in a person's DNA can cause cells in the adrenal gland 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 the way we look. It also determines our risk for developing certain diseases, including some types of cancer. Some genes (parts of our DNA) contain instructions.
