Shannen Doherty revealed that she has been diagnosed with stage 4 breast cancer.

On Tuesday (February 4), nearly three years after going into remission, the Beverly Hills, 90210 alum sat down with Good Morning America to share her heartbreaking health update and private battle.

"It's going to come out in a matter of days or a week that I have stage 4," she told anchor Amy Robach. "So my cancer came back and that's why I'm here."

Doherty was previously diagnosed with breast cancer in 2015.

"I’m petrified," she admitted after she was asked how she's handling the diagnosis. "I’m pretty scared. My mom is a ridiculously strong, courageous human being. So is my husband, but I worry about him."

"I don’t think that I’ve processed it. It’s a bitter pill to swallow in a lot of ways," Doherty continued. "There are definitely days where I say, ‘Why me?’ and then I go, ‘Well, why not me? Who else?’ Who else besides me deserves this? None of us do."

The 48-year-old actress said her first reaction upon learning of her cancer's return was how she would tell her mother and her husband. Then, when her good friend and former co-star Luke Perry suddenly passed away from a stroke last year, she asked herself, "Why wasn't it me?"

"It was so weird for me to be diagnosed and then somebody who was seemingly healthy to go first," she admitted. "It was really shocking and the least I could do to honor him was do that show. I still haven't done enough in my opinion."

Elsewhere in her GMA candid interview, Doherty revealed she went public with her health battle amid an ongoing lawsuit with her insurance company, who she is suing for damage done to her home during wildfires last year.

“I’d rather people hear it from me,” she explained. “I don’t want it to be twisted. I don’t want it to be a court document. I want it to be real and authentic, and I want to control the narrative. I want people to know from me.”

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