CA724, also known as gastric cancer antigen, is a test marker for detecting gastric cancer and various gastrointestinal tumors. However, CA724 is not a specific tumor marker, so when women find high CA724 in the test, it is not necessarily caused by tumor cells, but may also be caused by other factors that stimulate the occasional high CA724. However, the most common causes of high CA724 are gastric cancer, mucinous cystadenoma of the ovary, or non-small cell lung cancer, rectal cancer, etc.