Angelina Jolie has confirmed that she had a preventive double mastectomy earlier this year.
The actress and director made the decision upon finding out that she carries the BRCA1 gene, which can increase the risk of developing breast cancer and ovarian cancer.
Jolie, whose mother died of cancer at the age of 56, wrote an essay for The New York Times talking about her surgery and the discussions she had with her family - including her children - and said that she had chosen to share her experiences in the hope that others might benefit when it comes to making decisions about their health.
"Once I knew that this was my reality, I decided to be proactive and to minimize the risk as much I could," she wrote. "I made a decision to have a preventive double mastectomy... On April 27, I finished the three months of medical procedures that the mastectomies involved. During that time I have been able to keep this private and to carry on with my work.
"But I am writing about it now because I hope that other women can benefit from my experience. Cancer is still a word that strikes fear into people's hearts, producing a deep sense of powerlessness. But today it is possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer, and then take action."
Jolie revealed that following tests, her doctors estimated she had an 87% risk of developing breast cancer and 50% risk of developing ovarian cancer. She did, however, stress that the risk factors are different for each individual who carries the BRCA1 gene.
She added that following the three rounds of surgery, her chances of developing breast cancer have dropped to 5%.
"I wanted to write this to tell other women that the decision to have a mastectomy was not easy. But it is one I am very happy that I made," Jolie further revealed.
"I can tell my children that they don't need to fear they will lose me to breast cancer. It is reassuring that they see nothing that makes them uncomfortable. They can see my small scars and that's it. Everything else is just Mommy, the same as she always was. And they know that I love them and will do anything to be with them as long as I can.
> Read Angelina Jolie's essay 'My Medical Choice' in full
"On a personal note, I do not feel any less of a woman. I feel empowered that I made a strong choice that in no way diminishes my femininity.
"I am fortunate to have a partner, Brad Pitt, who is so loving and supportive. So to anyone who has a wife or girlfriend going through this, know that you are a very important part of the transition.
"Brad was at the Pink Lotus Breast Centre, where I was treated, for every minute of the surgeries. We managed to find moments to laugh together. We knew this was the right thing to do for our family and that it would bring us closer. And it has."
Jolie continued: "For any woman reading this, I hope it helps you to know you have options. I want to encourage every woman, especially if you have a family history of breast or ovarian cancer, to seek out the information and medical experts who can help you through this aspect of your life, and to make your own informed choices."
Adding that her own treatment programme would be published on the Pink Lotus Breast Centre website, she added that she appreciates there are alternatives to surgery, acknowledging the "many wonderful holistic doctors" working on such regimes.
.Jolie also highlighted the cost of BRCA1 and BRCA2 gene testing in the United States, arguing that figures of over $3,000 (£1,960) pose "an obstacle for many women".
"It has got to be a priority to ensure that more women can access gene testing and life-saving preventive treatment, whatever their means and background, wherever they live," she wrote.
Jolie concluded: "I choose not to keep my story private because there are many women who do not know that they might be living under the shadow of cancer. It is my hope that they, too, will be able to get gene tested, and that if they have a high risk they, too, will know that they have strong options.
"Life comes with many challenges. The ones that should not scare us are the ones we can take on and take control of."