“I touched my own boob — I don’t know why,” the Playing House star says in the current issue of PEOPLE. “I felt a lump and I instantly knew something was terribly wrong.”
Four days later, the then-38-year-old was diagnosed with stage 2B estrogen positive breast cancer.
“I was sobbing like a baby bird,” she says of being told her diagnosis. “But I remember thinking, ‘I will do anything and everything I need to do to stay alive for my daughter and make sure this has the least amount of impact on her life.’ “
St. Clair immediately signed up for the most aggressive chemotherapy treatment available to her and scheduled a double mastectomy. But she was worried her daughter would find out what she was going through. “She would get nervous if I went to Walgreens, so what would she think if I told her I had cancer?” says St. Clair.
She decided to try one of the “cancer hacks” recommended by her doctors: a “cold cap,” which may lessen hair loss during chemotherapy in some people. The chilled, tight, helmet-type hats constrict blood vessels and possibly prevent chemo from reaching hair follicles, according to breastcancer.org.
- For more from St. Clair — including how her costar Lennon Parham supported her through her cancer battle (including picking out her breast implants!) — pick up the latest issue of PEOPLE, on newsstands Friday
At some points during her treatment, St. Clair had to switch out her cold cap every 20 minutes for up to seven hours a day. But she says it was all worth it for her daughter.
“I’d tell her I was going to work and I’d go to chemo and with the cold cap,” says St. Clair, who leaned heavily on her friends — including her Playing House costar Lennon Parham — and her husband, playwright Dan O’Brien. “After the first 10 minutes you really don’t feel it. It’s just more of a pain to have a frozen rugby helmet on your head.”
And it worked. She kept most of her hair.
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“The amazing thing was on the outside you didn’t know anything was happening to me. I actually walked a red carpet for a show three quarters of the way through treatment,” she says. “But this wasn’t just vanity. When you’re a mother, these are really important things because it can save you from having a hard conversation that they aren’t going to understand anyway.”
St. Clair — who is now cancer-free — didn’t go public with her story until May when she wrote an essay for Stand Up to Cancer, but she now hopes sharing her experience can help other parents.
“Things like your hair and nails and eyelashes, those are important to your mental state. I think I was very lucky because my doctor, oncologist and plastic surgeon were all very much about ‘If you have to go through breast cancer, lets have it have a minimal impact on your life,’ ” she says. “There are a lot of young moms going through this and I want them to know, ‘Hey, I can do this too!’ “
Season 3 of Playing House — which will include a storyline inspired by St. Clair’s cancer story — premieres June 23 at 11 p.m. ET on USA.