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/ Source: TODAY
By Scott Stump

Shannen Doherty revealed on Tuesday that she will be undergoing an unspecified surgery.

The "Beverly Hills, 90210" and "Charmed" actress wrote on Instagram that she is "banking blood" for an upcoming procedure, a term used to describe storing and preserving one's blood in the event a blood transfusion is needed later.

"My doctor had me bank some blood for my upcoming surgery,'' the actress, 47, wrote.

In the photo, Doherty smiles next to a man who appears to work for the American Red Cross; "He was patient, kind and really good," she wrote.

Doherty, 47, was diagnosed with breast cancer in 2015. In April 2017, she said she was in remission.

In her latest update, Doherty also expressed her gratitude for those who donate blood.

"So two of them come every 2 weeks and donate platelets which takes 2 hours,'' she wrote. "Another girl comes as often as allowed to donate blood. To say I’m moved by the generosity of people is an understatement."

"I’m vowing that as long as I’m cleared in the future, I will start donating. Thank you to those selfless humans that donate. Thank you to Mars and all at the clinic in Woodland Hills for your smiles and hard work."

Doherty has been back to work since announcing in August that she is part of the television reboot of the classic 1988 movie "Heathers," following a two-year treatment for cancer.

Her latest health update comes on the heels of an Instagram video on April 4 in which she said she is still in remission despite an elevated tumor marker that turned out not to be related to her type of cancer.

She had initially posted a video saying one of her tumor marker tests came back elevated and said she was "staying positive," but she later deleted the post and put up a new video clarifying that she remains in remission.

"Still in remission,'' she wrote in the caption. "I imagine that I’ll always worry to a certain extent but I think we all worry about something. Cancer is a beast that changes one."

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