When she was diagnosed with breast cancer in October 2006, Cynthia Nixon was far from shocked. After watching her mother, Anne, 78, battle the disease three decades earlier, "I imagined there was a good chance I'd get it someday," says the Sex and the City actress. Thanks to surgery and radiation, Cynthia, 42, is cancer-free and, as a spokeswoman for Susan G. Komen for the Cure, educates women about the illness. She's one of several stars touched by the disease that PEOPLE will spotlight in coming weeks to celebrate Stand Up to Cancer, a fund-raising special airing live Sept. 5 on NBC, ABC and CBS. Cynthia and Anne spoke to PEOPLE's Natasha Stoynoff about winning their war with breast cancer.

PEOPLE Cynthia, how did you find out you had breast cancer?

CYNTHIA I had a completely routine mammogram when I was 40. The doctors found something very small and said, "We wouldn't think anything of it except it wasn't there last year." Luckily, because my mom had had breast cancer, I started to get mammograms at 35. If that was my first one, they might not have caught it.

ANNE Mine was discovered by me. It was large enough that my fingers could find it. So a little more of me got chipped away than with Cynthia.

PEOPLE What was your reaction?

CYNTHIA It didn't worry me too much. The doctors said, "The chances of this turning into anything really frightening are quite small." And my mother was diagnosed almost 30 years before, and she's perfectly healthy.

ANNE I had not been fearful of my cancer, so I was not fearful for her. Her girlfriend [union organizer Christine Marinoni, 41] was much more alarmed and shaky.

CYNTHIA Christine was the one with the tears. To her, cancer sounded like "Oh, she's gonna die!" What turned her around was talking to my surgeon. He talked about statistics and said, "Don't worry, this is totally treatable." I even had my kids [Samantha, 11, and Charles, 5] go in and speak to him. I told them, "This is what Grandma had. It's gonna be fine."

ANNE When I was diagnosed, I didn't want Cynthia to be scared about it. I had an aunt who had a mastectomy at 40, then another one at 55. And she lived to be, like, 89!

PEOPLE What was your toughest moment?

CYNTHIA The worst part was when they had to leave me in this X-ray machine and develop the pictures very quickly and then stick in needles while I was still in the machine. I was not allowed to move. My surgeon just held on to me because I said, "I'm going to faint." I was standing up, in a vise. I'm very squeamish. And then the nurse says, "I'm just going to change your robe because there's a lot of blood ..."

ANNE I had that too with my second cancer [years later]. It was just awful. When Cynthia came back to the room, Christine and I just patted her on the head.

PEOPLE How does it feel for you to talk to other women about your experiences?

CYNTHIA The only times I get emotional are when I'm at a Komen event and I am overwhelmed by the feelings all around me. I think women really draw strength from each other. They tell you when they were diagnosed and how many years it's been since their diagnosis. It's kind of like when men say, "Oh, you were in Korea? Me too. Where were you stationed?"

PEOPLE Sounds like you inherited your mom's fighting spirit.

CYNTHIA It was all in her tone. Her tone said, "Why would you worry about this more than anything else? Just because it has a label on it that says cancer? It's just a disease that you are coming down with."

ANNE That's the attitude!

For more information on Susan G. Komen for the Cure, go to www.komen.org.

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