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OTRC: Angelina Jolie makes first public appearance since mastectomy reveal

Angelina Jolie (L) and Brad Pitt attend the World Premiere of 'World War Z' at The Empire Cinema Leicester Square on June 2, 2013 in London. It marked Jolie's first public appearance since she revealed in May that she had undergone a double mastectomy. (Dave M. Benett / WireImage for Paramount)

Angelina Jolie joined fiance Brad Pitt at the London premiere of his newest film, "World War Z," marking her first public appearance since she revealed last month that she had undergone a double mastectomy as a preventative measure against breast cancer.

The 37-year-old actress wore a black, halter-style, cutout gown with a high neckline and sheer panel at the event, which took place at the Empire Cinema at Leicester Square on Sunday, told reporters that she is "grateful" and "very moved" by the support expressed by people following her announcement, which she had made via an Op-Ed piece published by the New York Times.

"I feel great, I feel wonderful and I'm very, very grateful for all the support -- it's meant a lot to me," Jolie told BBC News at the "World War Z" premiere.

The actress' mother, Marcheline Bertrand, died in 2007 at age 56 after battling breast cancer and ovarian cancer. Jolie's aunt, Debbie Martin, died of breast cancer at age 61 in late May. The actress had tested positive for the BRCA1 gene, which carried an 87 percent risk of contracting breast cancer. Her physician said last month that the actress underwent a double mastectomy in February and reconstructive cosmetic surgery on her chest in April.

Jolie last appeared in public on April 11, almost two months after her mastectomy. She attended the G8 Foreign Ministers meeting in London and gave a speech about sexual violence against women. (Check out more details and watch a VIDEO of Angelina Jolie making her speech.)

Following her announcement about her ailment, Pitt, who shares six children with the actress, had called her "absolutely heroic."

"He's been extraordinary, just extraordinary. He's just a wonderful man and a wonderful father and I'm very lucky," Jolie said at the premiere.

"I'm very happy just to see the discussion about women's health expanded and that means the world to me and after losing my mom to these issues," she added.

Pitt told BBC News that Jolie is a "very special woman."

"The beautiful thing is that for us, life will go on," he said. "Very moving experience -- certainly brought our family tighter together. Just the bravest thing to me. I get a little emotional about because of just the act itself -- which she did for our family -- and then bringing, telling the story to others and what it means to others really surprised me."

"World War Z" is set for release on June 21. Watch a trailer and a sneak peek clip below.

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