Dense breasts can make it harder to spot cancer on a mammogram KSL.comMammogram centers must now inform women about their breast density. Here's how it could affect you The Associated PressBreast Cancer Awareness Month: Joan Lunden reflects 10 years after beating disease, urges women to be aware of breast density ABC7 ChicagoAP Trending SummaryBrief at 12:03 a.m.