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On Monday, the actress opened up again, this time telling fans about the latest step and the anxiety that comes with it.
"First day of radiation treatment," she wrote in the caption of a photo on Instagram Monday.
"I look like I'm about to make a run for it which is accurate. Radiation is frightening to me. Something about not being able to see the laser, see the treatment and having this machine moving around you just scares me."
Doherty remains confident that she'll adjust to the new treatments, just as she has to all the demands in her fight against breast cancer, but she isn't hiding behind any false bravado about it.
"I'm sure I'll get used to it but right now.... I hate it," she wrote.
She added the hashtags "#radiationmondaysucks" and "#stillfightinglikeagirl" to her Instagram post.
The former "Beverly Hills, 90210" star first shared her fears about radiation a week ago, when a procedure meant to map out the treatment plan sparked a "full panic attack."
"Sometimes, you just get sick of being poked," she explained. "And that's ok. I cried. I felt sorry for myself for a minute. Then stopped and reminded myself of how lucky I am."
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