Is there a link between breast cancer and ovarian cancer?

The majority of ovarian cancers are still what we call sporadic, meaning that they occur and there's no genetic predisposition that we know of that put people at risk for that disease. However, about 20% or so of patients with ovary cancer do have a genetic basis for their disease. The way that they were born before they ever left their mother's womb put them at risk for cancerous processes and the most famous one that you'll hear about is the BRCA Mutation. Those patients are not only at risk for ovary cancers, but also have an overlapping risk for breast cancers too.