Christina Applegate by John Shearer/WireImage.com
After seeing her doctor, Christina Applegate "just knew" she was going to be diagnosed with breast cancer, the actress shared on Tuesday's episode of The Oprah Winfrey Show.

"I just knew. I went home and they called me and... [said] 'It came back positive,'" she said. "And I just - like right now I'm sitting here shaking remembering that moment."

The Samantha Who? star's mother, Nancy, is a two-time survivor of the disease, and "there was this part of me that sort of knew that the other shoe was going to drop," Applegate said.

Following her diagnosis, the 36-year-old made the " tough choice" to undergo a double mastectomy ("I was just gonna let them go") and felt no sadness in the decision until she met her surgeon.

"At first I didn't [cry]," she said. "And then when I met with my doctor and I told him that was my decision and he brought the surgeon in and it was like the flood gates just opened up and I - I lost it."

Thanks to the procedure, Applegate is now "absolutely 100 percent clear and clean" of breast cancer. - Joyce Eng

Related:
" Applegate Diagnosed with Breast Cancer; Full Recovery Expected
" Applegate "Clear" of Cancer Following Double Mastectomy