The 50-year-old actress spoke about changing the perception around stage 4 cancers on Tuesday during a virtual panel for her upcoming Lifetime movie List of a Lifetime, which centers around a woman who has been diagnosed with breast cancer.
"I feel like I have a responsibility in my more public life, which I separate from my acting life ... to talk about cancer and perhaps educate people more and let people know that people with stage 4 are very much alive and very active," she told reporters.
"My husband says that you would never know that I have cancer," added Doherty, who has been married to photographer Kurt Iswarienko since 2011. "I never really complain. I don't really talk about it. It's part of life at this point."
Starring Kelly Hu and Sylvia Kwan, List of a Lifetime follows Brenda Lee (Hu), a woman whose breast cancer diagnosis prompts her to seek out the daughter she gave up for adoption decades ago. When she reconnects with Talia (Kwan), the two make a bucket list for Brenda as she discovers a new meaningful relationship she didn't know she needed.
Calling the project "the first acting thing I've done about cancer" since announcing her own diagnosis last year, Doherty said she's been "pretty careful" about bringing her craft "into that world" but was drawn to film after reading its script.
"I didn't have to give anybody advice because [of director Roxy Shih] and these beautiful ladies who did such a beautiful job with their own preparation process," Doherty said of her costars. "We all showed up and honestly ... this was truly an unbelievable pleasure to be a part of, and I was blown away every second that I got to work with these amazing ladies."
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As for whether she personally has a bucket list like Hu's character, the Beverly Hills, 90210 alum said, "I just think a bucket list is odd in my particular situation because it means that I'm sort of trying to check things off before my time runs out."
"I'm very much like there's no bucket list because I'm going to be the longest-living person with cancer," she continued. "If I had to say one, it would just be living. That's the only thing on my list at this point."
Doherty was first diagnosed with breast cancer in 2015, she shared exclusively to PEOPLE at the time. She entered remission two years later, but revealed in 2020 that her cancer had returned as stage 4.
LISA O'CONNOR/AFP/Getty Shannen Doherty
Since then, Doherty has been vocal about disproving assumptions around stage 4 cancer patients and those who have terminal illnesses.
"I want people to not hear stage 4 cancer and think of the person that is gray and falling over and they can't move and they're going into hospice and they can't work," she told her longtime friend Sarah Michelle Gellar for an interview with Entertainment Tonight in October. "You get written off so quickly, even though you're vital and healthy and happy and wanting to go out there and work."
"Everybody's terminal," she added at the time. "I might live a lot longer than somebody who's perfectly healthy. You have no idea."