Sen. Claire McCaskill said Monday that she has breast cancer.
“It was detected through a regular mammogram,” the Missouri Democrat said in a post on Tumblr. “It’s a little scary, but my prognosis is good and I expect a full recovery.”
McCaskill said she would undergo treatment in St. Louis for the next three weeks. During that time, she plans to post online her positions on issues under consideration in the Senate.
Her office did not provide additional details on the diagnosis or the type of treatment McCaskill will pursue.
Reaction to the illness was swift.
“Claire and I work together every day, and I certainly wish her and her family the very best as she deals with this difficult diagnosis,” said Sen. Roy Blunt of Missouri in a statement. “I will step in in any way I can to help while she seeks treatment, and hope she makes a speedy recovery.”
Other colleagues joined in. “Praying for a quick and speedy recovery for @clairecmc” said a tweet from Sen. Lindsey Graham, a Republican of South Carolina.
McCaskill is 62. She was first elected to the U.S. Senate in 2006 after serving as Missouri auditor, Jackson County prosecutor and a state legislator. She was re-elected to the Senate in 2012.
She announced last year that she would not run for governor, but she is believed to be interested in running for the Senate when her current term expires in 2018.
A breast cancer expert said Monday that treatment for the disease is not necessarily debilitating.
“We understand the molecular bases for many of the subtypes of breast cancer, and because of that we’ve been able to create targeted therapies,” said Anne O’Dea, a breast medical oncologist at the University of Kansas Cancer Center. “I have patients who remain very active.”
Mammograms for younger patients have been controversial in recent years. Some studies suggest they’re not needed for women under 50 with no family history of the disease, although several women’s health advocacy groups have disputed those findings.
In any case, mammograms are considered routine for women who are McCaskill’s age. “Women age 55 and older should switch to mammograms every two years, or have the choice to continue yearly screening,” the American Cancer Society says. More frequent screenings are recommended for patients at risk for breast cancer.
McCaskill set no timetable for her return to Washington. “Thank you for the honor of serving you in the Senate,” her statement said.
Among well-wishes McCaskill received, many of them on Twitter:
U.S. Rep. Emanuel Cleaver, Democrat: “She’s a fighter, and like everything else in life that has tried to stop her, she will press through it. We will be there to help her.”
“Wishing my very best for a speedy recovery to one of the Senate’s toughest fighters, @clairecmc. The whole Twitterverse is here for you!” said Sen. Elizabeth Warren, a Massachusetts Democrat.
Republican House Speaker Paul Ryan: “Janna’s & my thoughts are with @clairecmc during this trying time.”
Sen. Marco Rubio, a Republican candidate for president: “Praying for my colleague Senator @clairecmc’s full and speedy recovery as she fights breast cancer.”
Jackson County Prosecutor Jean Peters Baker, who worked under McCaskill, said “there is little I am more certain of than you don’t pick a fight with Claire and walk away to tell about it. I know that she has a battle ahead of her, but she is the ultimate fighter.”
Joe Scarborough co-hosts a show on MSNBC that McCaskill often joins. “Mika and my prayers are with our dear friend Claire McCaskill who will fight and whip cancer. We love you, Claire,” he tweeted. Mika Brzezinski is the other host of the program.
“I swore and threw something when I saw this. God bless you, Senator @clairecmc...” tweeted MSNBC host Rachel Maddow.