Sen. Claire McCaskill of Missouri revealed on Tumblr this afternoon that she was recently diagnosed with breast cancer after getting a routine mammogram. “It’s a little scary, but my prognosis is good and I expect a full recovery,” she said.

McCaskill, 62, declined to provide any more information about her diagnosis. She is taking a three-week leave of absence to obtain treatment and will post on her website about any votes she misses.

Photo via Getty. Contact the author at allie@gawker.com.