Angelina Jolie won plaudits around the world when she announced in May that she'd had a pre-emptive double mastectomy once doctors told her she had a whopping 87 percent risk of developing breast cancer and a 50 percent chance of developing ovarian cancer. Jolie, who regularly leverages her fame for public good, said she chose to share her story in the hope that other women who may be living under the shadow of cancer will be able to get gene-tested" and know about their "strong options" in the event they've been dealt some unlucky genetic cards. While Jolie's decision to tell the truth about her situation was brave and extraordinarily well intentioned, how much of the truth was she told about her condition? Is her genetic history indeed an automatic death sentence? Here's what doctors may not have told her. Most breast cancer develops in women without a family history of the disease. The vast majority of women who get cancer (eight out of every nine) don't have a family history of the disease-and even with a family history, most women will never develop cancer. Four out of five women who have a mother and a sister with breast cancer will never develop the disease, and 12 out of 13 will not die from it. The danger increases with the number of close relatives who have the disease, but the risk may prove to be far less than that described to Jolie. For women who have one close relative with breast cancer, the lifetime risk is 8 percent, which increases to just 13.3 percent for those like Angelina Jolie, with two close relatives who had the disease. There is no solid evidence that just-in-case double mastectomies increase survival.