“My own personal 9/11” is how Martina Navratilova described the first day she discovered she had breast cancer. The tennis legend announced Wednesday that a biopsy came back positive for breast cancer after a routine mammogram late February. The prognosis is “excellent,” says People magazine; the cancer is a non-invasive form called ductal carcinoma in situ, or DCIS, which means it is confined to the milk ducts and has not spread. Navratilova lamented letting her health slide, waiting four years between mammograms: “Here I am, the health and fitness ambassador for AARP, speaking to millions each month about staying healthy and I let my annual check-ups fall to the bottom of my to-do list. It’s not all about eating right and exercising. Preventative steps can make just as much, or in some cases more, of a difference. Getting my mammogram literally saved my life.” According to Cancer Research UK, the Guardian notes, individuals who are diagnosed with DCIS and treated will almost certainly be cured of the disease.