Simply having or having had cancer is a risk factor for metastases. Some cancers are more likely to spread than others. Still, doctors can’t predict who will develop metastatic cancer over time.
Certain genetic changes must occur for cancer to spread to other organs. And where it spreads depends on its type, size and where it started in the body. Even when these things are known, doctors aren’t always sure if a person’s cancer will metastasize.