In the episode, Brenda does an at-home breast exam and finds a lump in her left breast. She later undergoes a biopsy. While her character receives a clean bill of heath, Doherty herself now faces the worst possible situation.
>> Shannen Doherty's latest health update isn't something fans ever wanted to hear
Doherty told fans earlier this week that the cancer has spread to her lymph nodes. She underwent a single mastectomy in May and is currently working through eight rounds of chemotherapy. Once she finishes the chemo, Doherty will undergo radiation treatments.
“Back then, I was a kid, man — I thought that I was invincible, I thought I was going to live forever,” she said.
>> Actress Shannen Doherty shaves head amidst cancer battle, shares on social media
Doherty had public fallouts with some of her “90210” castmates, but remains close with Jennie Garth, Brian Austin Green, Jason Priestley and Ian Ziering.
“I’ve heard from quite a few of my costars,” she said. “They know who they are. I don’t feel l like I need to point them out, and I thank them from the bottom of my heart for reaching out to me.”
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The conclusion of Doherty’s interview with "Entertainment Tonight" airs Wednesday.