Tennis great Martina Navratilova is being treated for ductal carcinoma in situ (DCIS) found in her left breast in January. USA Today explains, DCIS is the most common type of non-invasive breast cancer and is sometimes referred to as Stage 0 or precancer. Though DCIS is hardly ever life-threatening, it carries an increased risk of invasive cancer down the road.
More and more physicians are speaking out and saying that DCIS should not be called cancer, says Dr. Whelan. Women with DCIS who have a lesionectomy -- sometimes followed by a course of radiation -- reduce their risk of developing invasive cancer compare to women who don t have it removed. Still, DCIS is non-invasive, and may lose its official status as cancer in the future.