Olivia Munn, 43, Reveals She Was Diagnosed with Breast Cancer and Had Double Mastectomy

Olivia Munn has been diagnosed with breast cancer.

On Wednesday, the X-Men: Apocalypse actress, 43, posted a series of photos on Instagram from last year when she was undergoing treatment in the hospital after learning of her diagnosis.

“In February of 2023, in an effort to be proactive about my health, I took a genetic test that checks you for 90 different cancer genes,” she began. “I tested negative for all, including BRCA (the most well-known breast cancer gene). My sister Sara had just tested negative as well. We called each other and high-fived over the phone. That same winter I also had a normal mammogram.”

“Two months later I was diagnosed with breast cancer,” she continued. “In the past ten months I have had four surgeries, so many days spent in bed I can't even count and have learned more about cancer, cancer treatment and hormones than I ever could have imagined."

"Surprisingly, I've only cried twice. 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," Munn added.

Munn said she kept the diagnosis and recovery private until now because she “needed to catch my breath and get through some of the hardest parts before sharing.”

The actress admitted that she wouldn't have found her cancer if it weren’t for her “guardian angel” OB/GYN Dr. Thais Aliabadi, who’s known for working with stars like Rihanna and Khloé Kardashian.

She said Aliabadi decided to calculate her Breast Cancer Risk Assessment Score. “The fact that she did saved my life,” Munn said.

“Dr. Aliabadi looked at factors like my age, familial breast cancer history, and the fact that I had my first child after the age of 30. She discovered my lifetime risk was at 37%. Because of that score I was sent to get an MRI, which led to an ultrasound, which then led to a biopsy. The biopsy showed I had Luminal B cancer in both breasts. Luminal B is an aggressive, fast moving cancer.”

Munn said that 30 days after her biopsy, she had 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 wrote. “I'm lucky. We caught it with enough time that I had options. I want the same for any woman who might have to face this one day.”

Munn urged others to be proactive about their health and ask their doctors to calculate their Breast Cancer Risk Assessment Score and to get annual mammograms and breast MRIs starting at age 30 if the number is greater than 20%.

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The Newsroom actress added that she’s “grateful” for the staff at Cedars-Sinai in Los Angeles and Saint John's in Santa Monica for their help during treatment. She ended the post by praising her loved ones for supporting her through the difficult health battle.

“I'm so thankful to my friends and family for loving me through this. I'm so thankful to [John Mulaney] for the nights he spent researching what every operation and medication meant and what side effects and recovery I could expect,” she wrote. “For being there before I went into each surgery and being there when I woke up, always placing framed photos of our little boy Malcolm so it would be the first thing I saw when I opened my eyes.”

“Thank you to the friends who've had breast cancer and the friends who connected me to friends who've had breast cancer for guiding me through some of my most uncertain and overwhelming moments,” Munn added.

Wrote Mulaney, 41, in a comment on her post, "Thank you for fighting so hard to be here for us," adding of their 2-year-old son, "Malc and I adore you. ❤️"