This is so scary. Kate Walsh may have done the perfect portrayal of Dr. Addison Montgomery on Grey’s Anatomy and Private Practice for all those years, but at one point she was a patient herself. In a new interview, the actress revealed she was once diagnosed with a brain tumor.

It happened back in June 2015, but Kate, 49, is speaking out about it now to Cosmopolitan. “I got an MRI and thank God I did, because it turned out I had a very sizable brain tumor in my left frontal lobe. And three days later I was in surgery having it removed,” she said of the lemon-sized tumor, which was eventually determined to be benign.

Kate added, “She starts to say, ‘Well, it looks like you have a very sizable brain tumor’ — and I just left my body. My assistant had driven me there, and I had to go get her so that she could take notes because I was gone. It was never anything I would have imagined.” And even though she had all that experience as a TV doctor, she was still absolutely terrified by the whole incident (as she should have been).

“It was the total opposite! You’d think that after playing Dr. Addison for the better part of a decade, where I spent more time on a hospital set than at my house, that I would feel somehow more comfortable, but I was such a little scaredy-cat,” she admitted. “In the hospital, I felt like I might as well be six years old. My mother gave me rosary beads, my friend gave me a stuffed animal to go into surgery with… I played a real badass on TV, but when it comes to being a patient it’s such a vulnerable experience.” We’re glad Kate is feeling better today — and we’re crossing our fingers that she’ll make a surprise cameo on Grey’s this upcoming season!