Why Shannen Doherty Kept Cancer Secret While Working on '90210' Reboot

Actress Shannen Doherty has revealed she was diagnosed with stage 4 breast cancer a year ago and kept the diagnosis out of the public eye while filming the reboot of "90210."

"It's going to come out in a matter of days or a week that — I'm stage four. So my cancer came back," Doherty said in a interview that aired on "Good Morning America" Tuesday. "I don't think I've processed it. It's a bitter pill to swallow in a lot of ways."

Doherty, 48, starred as Brenda in the hit teen drama series "Beverly Hills, 90210." Other roles included Jenny in "Little House on the Prairie" and Prue in "Charmed." 

She was initially diagnosed with breast cancer in 2015, but went into remission following treatment, which she documented on social media. 

This time, however, Doherty kept the diagnosis private while working on the set of the reboot of "90210." She wanted to show others that she could still work and that life "doesn't end the minute we get that diagnosis," she said in the interview.

For Doherty, continuing with the reboot was also about honoring former castmate Luke Perry, who died suddenly of a massive stroke four months before the start of shooting in 2019.

"It's so weird for me to be diagnosed and then somebody who was, you know, seemingly healthy to go first," Doherty said. "It was really, like, shocking. And the least I could do to honor him was to do that show. I still haven't done, in my opinion. So it's a hard one."