She's shared her journey with fans, who have lent their support and love.
That may have prompted Shannen Doherty to share a very personal, very raw moment on Instagram, in which she decided to shave her head in preparation for chemotherapy.
Doherty was diagnosed with breast cancer in March 2015 after legal documents were leaked, revealing that she was suing her former management company for not paying her insurance premiums.
This, Doherty claimed in the suit, prevented her from catching the cancer earlier.
Last night, she invited her mother and a friend over while she went through the emotional steps, as recorded via Instagram.
Doherty appeared on Dr. Oz back in February, and revealed that she might opt for a mastectomy.
"I'm actually going to a center, just to sort of get their general opinion and then I head back to L.A. and instantly go in with my doctors," she explained.
"You know, I'm like 'You guys make the final decision. What would you do if it was your wife? What would you do if it was your daughter?'"
If it came to that point, Doherty revealed she was at peace with the decision.
"Ultimately, they're just breasts right?" she said.
"I mean, I love them, they're mine, they're beautiful, but in the grand scheme of things, I would rather be alive and I would rather grow old with my husband."
After the appearance, Dr. Oz gave Entertainment Tonight an update on Doherty's health.
"Shannen was very transparent about what's going on in her breast," Dr. Oz said.
"She has decided to have the breast cancer to removed surgically, and that is a big decision for a woman… It was really up to Shannen to decide she was ready to go through an operation she feared would be disfiguring."
Doherty married photographer Kurt Iswarienko in October 2011.
Doherty's decision to shave her head indicates that she's begun or has already started chemotherapy, which can cause hair loss in some patients.