Shannen Doherty Shares Photo of Her Completely Shaved Head: It Was an 'Impossibly Tough Day'

The actress got the dramatic haircut amid her battle with breast cancer.

Shannen Doherty posted a pic of the final result of shaving her head last week.

The 45-year-old actress has been battling breast cancer, and had the support of her friends and family when she decided to get rid of her brunette locks. On Monday, she posted a photo of herself, almost completely bald, posing with her support system.

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"Thank you to these three who helped me thru an impossibly tough day and continue to be there every minute supporting and loving me," she shared. "[My husband] @kurtiswarienko was in Mexico working but knew he left me in good hands. @annemkortright @chriscortazzo #mamarosa I love you. #mycrew #thisisasquad."

Doherty's friend, Anne Marie Kortright, praised the Beverly Hills, 90210 star for her courage. "@theshando I couldn't be prouder of you today," she posted last week. "Your strength and courage is so inspiring and I am so very lucky to have you in my life. Thank you for blindly trusting me today to help you with such a big step. I will forever be there for you no matter what."

Last August, Doherty revealed her breast cancer diagnosis in a lawsuit against her former management team, claiming that a likely mastectomy and chemotherapy treatment potentially could have been avoided had her health insurance coverage been kept up to date.

She then appeared on The Dr. Oz Show in February, and revealed that she had yet to make the decision between a mastectomy and a lumpectomy to remove her cancer. "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."

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"Shannen is juggling those two decisions -- neither one is perfect but both are acceptable, as long as the cancer comes out," Dr. Mehmet Oz told ET following his interview with Doherty. "The part of Shannen's story that's most stunning to me is that she's had that cancer in her breast for over a year and hasn't had it taken out yet – [the] cancer's still in there."

Dr. Oz added, "Thankfully, if we aggressively can treat it, we can save Shannen's life, and her doctors are superb and they're all over that decision."