Former President Joe Biden's office announced on Sunday that he was diagnosed with an "aggressive" form of prostate cancer. Here's what to know about the disease.

Former President Joe Biden's diagnosis with an advanced stage of prostate cancer that has metastasized, or spread, to his bones prompted an outpouring of concern and questions about his condition. Those questions include how long the cancer may have taken to develop and whether he was screened for it during earlier checkups.