Kathy Bates on Battling Cancer Twice and Surviving Lymphedema: 'I Felt That Life Was Over'

On Sept. 7, Kathy Bates will join Reese Witherspoon, Matthew McConaughey and Jennifer Garner for the biennial fundraising special Stand Up to Cancer. The event, which raises money for cancer research is a very personal one for the Oscar winner, 70, who has beat cancer twice.

In 2003, Bates, then 55, was diagnosed with stage 1 ovarian cancer and immediately had surgery, followed by nine months of chemotherapy to treat it, but didn’t reveal her illness to the public.

“I didn’t tell anybody,” she tells PEOPLE. “I continued to work right after the operation, doing Little Black Book with Brittany Murphy. My agent at the time was very old-school and didn’t want me to be the poster child for ovarian cancer. I didn’t want anyone to know, but it really took a lot out of me.”

Then, in 2012 the Memphis native—who got her start in theater and went on to star in films such as Misery, Dolores Claiborne, Fried Green Tomatoes and Titanic—was once again hit with extreme exhaustion and returned to her doctor for an MRI. She was diagnosed with breast cancer and decided to have a double mastectomy because of her family history with cancer.

“My aunt had died from it, my mother had it, my niece had it,” she says. She tested negative for the BRCA1 and BRCA2 gene mutation that increases a woman’s risk of breast and ovarian cancer. A negative BRCA result is “not a get out of jail free card,” she says.

Now, though she’s cancer-free, Bates says she is dealing with her biggest challenge yet: lymphedema, a disease that’s commonly caused by the removal of lymph nodes during cancer treatment. It causes extreme pain and swelling and has no cure. “It’s a souvenir you definitely don’t want,” says Bates about lymphedema adding after the diagnosis. “I really felt that life was over for me. I probably wouldn’t work again, and I was angry for a long time.”

For more on Bates, pick up this week’s issue of PEOPLE on newsstands now.

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Then Bates decided to turn her frustration into good by helping raise awareness about lymphedema and became the National Spokesperson for the Lymphatic Education & Research Network (LE&RN). She’s working on getting a bill passed in New York that will mandate that hospitals have literature to inform patients about lymphedema, and she’s learned to manage her own pain by wearing compression sleeves on her arms and losing 60 lbs. through exercise and a healthy diet.

Today her career is booming, including roles in the new season of American Horror Story and the upcoming film On the Basis of Sex. “Acting is my life force,” she says, adding that she considered getting breast reconstruction but doesn’t want to take time out of her busy schedule for surgery because “I’m having too much fun.”

Her advice to women: Get regular checkups and stay healthy. “Quit taking the damn selfies and worrying about what you look like,” she says. “Instead, keep everything working and in good order.”

Watch Stand Up To Cancer airing on networks including ABC, Fox, CBS and NBC and streaming live on PeopleTV Friday, September 7 at 8PM ET/PT. Go to PeopleTV.com or download the PeopleTV app on your favorite mobile or connected TV device.