After serving in the U.S. Senate for 10 years, Sen. Claire McCaskill, D-Missouri, announced this afternoon that she has breast cancer.

“I very recently learned that I have breast cancer,” McCaskill [posted](http://clairecmc.tumblr.com/post/139807035977/i-very-recently-learned-that-i-have-breast-cancer) on Tumblr. “It was detected through a regular mammogram. It’s a little scary, but my prognosis is good and I expect a full recovery.”
For the next three weeks, she will be receiving treatment in St Louis, McCaskill said in her Tumblr post.
“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,” McCaskill said in the post.

McCaskill also said she will also be submitting written questions for any Senate hearings she misses.

_Edited by Hailey Stolze | hstolze@themaneater.com_