(CNN)Shannen Doherty has even more bad news.
The 45-year-old actress told Entertainment Tonight that her breast cancer has spread and she's had a single mastectomy.
"I had breast cancer that spread to the lymph nodes, and from one of my surgeries we discovered that some of the cancer cells might have actually gone out of the lymph nodes," Doherty said. "So for that reason, we are doing chemo, and then after chemo, I'll do radiation."
Doherty, who was diagnosed with breast cancer in February 2015, called the mastectomy "traumatic and horrible." But said the trauma of the surgery hit her when she got fitted for a new bra.
"My mom went with me and I broke down crying in the dressing room and ran out," she said. "And then sat in the car crying."
Doherty is hopeful, but also terrified of the "unknown."
"Is the chemo going to work? Is the radiation going to work?" she continued. "You know, am I going to have to go through this again, or am I going to get secondary cancer? Everything else is manageable. Pain is manageable, you know living without a breast is manageable. It's the worry of your future and how your future is going to affect the people that you love."
Doherty did not reveal whether she plans to have reconstructive surgery, but did say the surgeon implanted an expander after removing her breast. This is commonly a precursor to either breast reconstruction or a breast implant.
The former "90210" star recently shaved her head and shared the intimate moment on Instagram. But the main reason she wanted to share her story is to hopefully help someone going through the same thing.
"I wanted to put it out there the way it felt the best for me to put it out there," she said. "And also, if I could help one person then it makes me go, 'Oh OK.' It's easier to live with having cancer if I know I'm helping at least one person."