Oliva Munn is giving more insight into her health journey.

While announcing that she had been diagnosed with breast cancer, The Newsroom actress shared that she had undergone major surgery during her treatment. 

As Olivia noted in her March 13 Instagram message, after a visit with her gynecologist, an MRI, an ultrasound and a biopsy, she underwent a double mastectomy.

"I went from feeling completely fine one day, to waking up in a hospital bed after a 10-hour surgery the next," she continued, but added, "I'm lucky. We caught it with enough time that I had options."

The 43-year-old admitted that she wouldn't have found her cancer for another year until her next scheduled mammogram and credited her doctor for calculating her Breast Cancer Risk Assessment Score. 

As she put it, "The fact that she did saved my life."

Two months before her diagnosis, the X-Men: Apocalypse star had her yearly mammogram and took a genetic test, which had negative results.

In total, Olivia—who shares son Malcolm, 2, with John Mulaney—underwent four surgeries during her treatment. 

"Surprisingly, I only cried twice," she wrote. "I guess I haven't felt like there was time to cry. My focus narrowed and I tabled any emotions that I felt would interfere with my ability to stay clearheaded."

But she also took a moment to express her appreciation to her loved ones, who had been there to support her. And Olivia's post received an outpour of support, including from John, who couldn't help but cheer on his partner.

"Thank you for fighting so hard to be here for us," he wrote in the comments. "Malc and I adore you."

Katie Couric, who was diagnosed with breast cancer in 2022, wrote, "Sending you love and gratitude for sharing this."

Keep reading to see who else shared messages of support.

After Olivia Munn shared her breast cancer diagnosis on Instagram March 13, she received a flood of well-wishes from fans, friends and fellow stars.

"Thank you for fighting so hard to be here for us," the comedian wrote to his partner. "Malc and I adore you."

"Thank you for sharing this!" the Big Bang Theory actress commented on Instagram. "Wow."

"You are so strong Olivia!" the Fellow Travelers star wrote. "Grateful you found this early. Sending you love always."

"Sending you and your family love & healing vibes," the Modern Family alum commented. "You are so strong."

"I love you friend," the Emmy winner told her pal. "May God continue to bless you with good health and a long happy life."

"Your experience is so powerful to share!" the Sex and the City actress commented. "Sending you so much love and strength , so grateful you found out early and can only imagine the emotional roller coaster you have been on."

The Office alum commented, "I love you."

"You are brave and strong and I’m thankful you are ok," the Olympic athlete wrote. "Sending all the love."

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