Speaker of the House Paul Ryan, MSNBC's Rachel Maddow and others took to Twitter to express their support for McCaskill

By Andrea Park
Updated February 23, 2016 12:45 PM
Credit: Astrid Riecken/Getty

Missouri Senator Claire McCaskill announced Monday that she is battling breast cancer.

In a Tumblr post titled “I very recently learned that I have breast cancer,” McCaskill discusses being diagnosed, getting treatment and continuing to serve her constituents.

“It was detected through a regular mammogram,” she writes. “It’s a little scary, but my prognosis is good and I expect a full recovery.”

McCaskill, 62, says that she’ll receive treatment in St. Louis for the next three weeks.

“During this time my staff will continue to assist Missourians and I will be posting on my Senate website how I would have voted on any matters that come before the Senate during my absence – which I’ll also enter into the Congressional record,” she writes. “Additionally, I’ll be submitting questions in writing for any missed Senate hearings.

“Thank you for the honor of serving you in the Senate,” she finishes. http://clairecmc.tumblr.com/post/139807035977/i-very-recently-learned-that-i-have-breast-cancer

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Many politicians and political reporters took to Twitter soon after McCaskill’s announcement to express their support for the senator, including Hillary Clinton, Massachusetts Senator Elizabeth Warren, Speaker of the House Paul Ryan, MSNBC reporter Rachel Maddow and New York Senator Chuck Schumer.

McCaskill, a Democrat, has served as a felony courtroom prosecutor, sat in the Missouri State Legislature and was the first female county prosecutor in Jackson County, the largest county in Missouri. She became the first female Missouri senator in 2006 and won re-election in 2012.