"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. So for that reason, we are doing chemo, and then after chemo, I'll do radiation," Doherty, 45, said.
"The unknown is always the scariest part. Is the chemo going to work? Is the radiation going to work?" she continued. "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 was diagnosed with breast cancer in February 2015. She had a single mastectomy this past May.
"[The doctor] didn't want me to wake up with absolutely nothing," she recalled. "It was very important to him that I didn't have that experience, and so, he put an expander in, so I have a tiny something there. It's cute and sometimes we fill it up and make it bigger, and sometimes we reduce it."
Doherty is trying to stay positive amid her health scare. However, the past few months haven't been easy. She told ET that she went for a "traumatic and horrible" bra fitting after the surgery.
"I didn't think anything of it at the time. Then my mom went with me and I broke down crying in the dressing room and ran out," she said. "And then [I] sat in the car crying."
Doherty hopes that her experience will comfort other women who are going through the same thing. She's been documenting her journey on social media, and debuted a completely shaved head via Instagram last week.
"After my second treatment, my hair was really matted, like in dreadlocks. And I went to try and brush it out, and it just fell out. I just remember holding onto huge clumps of my hair in my hands, and just running to my mom crying, like, 'My hair, my hair, my hair, my hair,'" she said. "It was just shedding and it was driving me crazy. It was just clumps, and I was like, 'Just grab the kitchen scissors.' … We did stages. We did a pixie. And then we did a Mohawk, which was my favorite look. And then finally, we had to get the shaver thing and just buzz it off."
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