Former Senator Bob Dole announced Thursday that he has been diagnosed with Stage IV lung cancer.

The 97-year-old former Senate Majority Leader made the announcement on Twitter Thursday, writing that his first treatment will begin Monday.

"While I certainly have some hurdles ahead, I also know that I join millions of Americans who face significant challenges of their own," Dole wrote in a statement.

Following Republicans winning back the House and Senate in 1994, leading to him serving his second stint as Majority Leader, Dole ran for president against Bill Clinton in 1996, but lost in an Electoral College landslide (379–159) to the incumbent. He is the last World War II veteran to have been the nominee of a major political party for president, and retired from politics shortly thereafter.

Dole sought the nomination for vice president on Gerald Ford's ticket, but lost, and mounted unsuccessful bids for president in 1980 and 1988.

Dole represented Kansas in the Senate for 27 years, and as a member of the House of Representatives for 8 years prior.

Kansas' governor, Laura Kelly, wished her "friend" a "swift recovery."

Former White House communications director Alyssa Farah offered prayers for Dole "and his wonderful family."

The Elizabeth Dole Foundation, established by Dole's wife, former North Carolina Senator Elizabeth Dole, wrote on Twitter that the former Kansas senator "will face this challenge as he has so many others, with his characteristic strength, optimism, & clever wit. The Foundation extends all our love & support to both Senators Dole."

In 2018, Dole was awarded the Congressional Gold Medal, the highest honor the legislature can bestow.

"Bob, that is the legacy that you have left our nation and it will outlive us all," then-President Donald Trump said at the ceremony, adding that in hearing Dole's story, "they will truly learn what it means to be a great American."

This is a developing story. Check back later for further updates.