News Rush Limbaugh and Shannen Doherty have advanced cancer. What does that mean? What is stage IV? February 6, 2020 Ryan W. Miller, USA TODAY Comments Off on Rush Limbaugh and Shannen Doherty have advanced cancer. What does that mean? What is stage IV? Rush Limbaugh announced he had "advanced lung cancer" and Shannen Doherty said she was diagnosed with stage IV cancer. Here's what cancer stages mean.