Angelina Jolie appearance will be the first time she's hit the red carpet since announcing she had a preventative double mastectomy.
She said she discovered she had BRCA1, a "faulty gene" that she said gave her an 87 percent chance of developing breast cancer and a 50 percent chance of developing ovarian cancer.
Jolie praised Pitt in the piece, for his tremendous support as she went through the series of procedures.
"I am fortunate to have a partner, Brad Pitt, who is so loving and supportive," she wrote in the NYT piece. "Brad was at the Pink Lotus Breast Center, 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."
The actress lost her mother, Marcheline Bertrand in 2007 to ovarian cancer. Bertrand's sister, Debbie Martin (who is Jolie's aunt), passed away over the Memorial Day weekend, following a battle with breast cancer.
Martin's funeral is expected to be held on Sunday, her husband, Ron Martin, told that "Angelina will be in London on Sunday so she won't be able to attend but she has been in touch with us and with various other members of the family, which has obviously been lovely and has meant a lot to us," he told the site.