John Mulaney Jokes About Olivia Munn Having ‘Cancer Brain’

John Mulaney kicked off the new season of his Netflix talk show with a story about wife Olivia Munn’s “cancer brain.”

“Yes, I have two children now. One was controversial, one you all seem to be cool with,” Mulaney, 42, joked during the premiere of Everybody’s Live With John Mulaney on Wednesday, March 12. “So, thank you so much for that. I did want to say something: Over the past few months, many people have reached out in a very nice way about my wife Olivia who’s been battling breast cancer. I really appreciate all the nice messages that obviously she has received and that even I have received.”

The comedian continued: “But it’s been a real thing to be with someone you love so much going through this. In the past couple years, Olivia has had five surgeries, months and months of cancer treatment, and the fight that she’s put up has made her so inspiring. And the effect of cancer treatment on her brain has made her, at times, so dumb.”

As Mulaney explained, “There’s a thing called cancer brain: not brain cancer. Cancer brain. It’s a sweet, wonderful dumbness that happens after all that challenging treatment. I’ll give you an example. We went to a fertility doctor, we were going to make embryos. This was after Olivia had a double mastectomy, but before her hysterectomy and ovariectomy. We were going to make embryos for what eventually became our daughter this fall.”

Related: John Mulaney Reveals ‘Only Reason’ Wife Olivia Munn’s Cancer Was Discovered

John Mulaney and his wife, Olivia Munn, both faced a startling new normal when she was diagnosed with breast cancer. “There’s this lifetime risk assessment test that is really the only reason her cancer was discovered,” Mulaney, 42, said on the Sunday, March 9, broadcast of CBS Sunday Morning. “Seeing so many women publicly and […]

He recalled that he and Munn, 44, “were standing in the doctor’s office and this conversation happened word for word. Doctor: ‘The great news is nine eggs survived the thaw.’ Olivia: ‘So now, we uh, combine it with his, uh, cum?’” 

At the time, Mulaney corrected Munn, saying, “Baby, baby. It’s semen,” while the doctor stated: “Guys, it’s sperm.”

Munn revealed in March 2024 that she had been diagnosed with cancer one year earlier.

“I took out my uterus, fallopian tubes, and ovaries,” she told Vogue in May 2024. “Doing a full hysterectomy was a big decision to make, but it was the best decision for me because I needed to be present for my family.”

Related: John Mulaney Has Given Olivia Munn ‘Strength’ During Breast Cancer Battle

Stefanie Keenan/WireImage After being diagnosed with breast cancer, Olivia Munn is leaning on boyfriend John Mulaney for support. “John has been a huge pillar of strength for Olivia throughout her health scare,” a source exclusively tells Us Weekly, noting that the couple’s 2-year-old son, Malcolm, also gave Munn, 43, the ”courage and strength to keep […]

Munn and Mulaney, who tied the knot in 2024, are parents to son Malcolm, 3, and daughter Méi, 9 months. (They welcomed Méi via surrogate amid Munn’s breast cancer battle.)

“There’s this lifetime risk assessment test that is really the only reason her cancer was discovered,” Mulaney said on the March 9 broadcast of CBS Sunday Morning. “Seeing so many women publicly and privately come to her that [say] they discovered how high their risk was from that, it’s astonishing.”