9Olivia Munn revealed she was diagnosed with breast cancer.oliviamunn/Instagram9She underwent a double mastectomy.oliviamunn/Instagram9The actress shared that she has had 4 surgeries over the course of 10 months.oliviamunn/InstagramEXPLORE MORE

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Her doctor prompted the actress to go for an MRI, then an ultrasound and finally a biopsy that confirmed she had luminal B cancer in both breasts, which is an “aggressive, fast moving cancer.”

Munn underwent a double mastectomy 30 days later and has gone through four surgeries total over the past 10 months.

“I went from feeling completely fine one day, to waking up in a hospital bed after a 10-hour surgery the next,” she wrote.

9“I went from feeling completely fine one day, to waking up in a hospital bed after a 10-hour surgery the next,” she wrote on Instagram.oliviamunn/Instagram9Her exact diagnosis was Luminal B cancer in both breasts, which is an aggressive form of the disease.oliviamunn/Instagram9She credited her partner, John Mulaney, for his support.oliviamunn/Instagram9“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.”

The “X-Men: Apocalypse” star credited her family, friends and partner, John Mulaney, for their support throughout her cancer journey.

“I’m so thankful to John for the nights he spent researching what every operation and medication meant and what side effects and recovery I could expect,” she continued.

“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.”

9The comedian and Munn have been together for three years.Oliviamunn/Instagram9They attended the Vanity Fair Oscars party together Sunday.