Shannen Doherty took to Instagram on Monday, November 28, to document her first round of radiation treatment for breast cancer, which she described as “frightening.”

“First day of radiation treatment. I look like I'm about to make a run for it, which is accurate,” the actress, 45 — who shaved her head in June — captioned a photo of herself sitting anxiously in a doctor’s office chair. “Radiation is frightening to me.”

The Charmed alum continued, “Something about not being able to see the laser, see the treatment and having this machine moving around you just scares me. I'm sure I'll get used to it but right now ... I hate it. #radiation #radiationmondaysucks #stillfightinglikeagirl.”

As previously reported, Doherty revealed her February 2015 breast cancer diagnosis in August 2015 in a lawsuit against her former business management firm. In the court documents, she claimed that her cancer spread because her health insurance wasn’t up-to-date and she couldn’t receive proper care.

Since then, she has been open about her journey, both on social media and in interviews. Back in October, Doherty opened up to Chelsea Handler about the transformative effect of her illness.

“I think what’s beautiful and hard and interesting about cancer is that it tears you down and builds you, and tears you down and builds you,” she explained. “It remakes you so many different times. The person I thought I was supposed to be or was going to be or who I thought I was six months ago is now somebody completely different.”

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