"1 in 8 women get breast cancer. Today, I'm the one," she wrote. "The good news is that I have the most glorious group of supportive and caring family and friends, and fantastic insurance through my union."
"The bad news is that not all women are so lucky, so let's fight all cancers and make universal health care a reality," she added, using her announcement as a call to action regarding universal health care.
The announcement comes just 11 days after the 56-year-old actress picked up her sixth Emmy in a row for her work on HBO series "Veep," a new record for consecutive wins.
When reached for further comment, a spokesperson for Louis-Dreyfus told TooFab: "Julia is incredibly grateful for the outpouring of support and well wishes. We have no further details to provide at this time. We appreciate your understanding."
The final "Veep" season will air in 2018 and if the actress wins again she would break another record: most Primetime Emmy wins by a single performer. Her eight wins throughout her career currently tie Cloris Leachman's Emmy achievements.
Louis-Dreyfus captioned the photo: "Just when you thought..."
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