For more than a decade, cancer has been Judith Hetlage's constant companion, always present and threatening. What began with a diagnosis of synovial sarcoma, a rare tumor in the connective tissue of ...

These are sometimes called fourth-generation tests. One distinctive HIV antigen is a viral protein called p24, a structural protein that makes up most of the HIV viral core, or 'capsid'. High levels ...

They need to hunt for clues. One way they can do that is with a carcinoembryonic antigen test. It measures a protein called CEA in the blood. People with some types of cancers have higher than ...