White House chief of staff Susie Wiles was diagnosed with “early stage” breast cancer, President Donald Trump said Monday.

In a post on Truth Social, Trump said that Wiles would begin treatment immediately and would remain in her role.

“She has a fantastic medical team, and her prognosis is excellent!” he said. adding, “During the treatment period, she will be spending virtually full time at the White House, which makes me, as President, very happy!”

Other members of the administration and lawmakers expressed their sympathies for Wiles in social media posts shortly after Trump’s announcement.

White House deputy chief of staff James Blair praised Wiles in a post to X, saying, “she will win this battle with grace.” House Speaker Mike Johnson, R-La., said his family “joins with everyone else in praying for our dear friend Susie to make a quick and complete recovery.” Rep. Lisa McClain, the House Republican Conference Chair, said in a post to X that she was praying for Wiles and called her “one of the strongest fighters in Washington.”

Wiles has served as Trump’s chief of staff since the beginning of his second term. She also served as the president’s co-campaign manager for his 2024 campaign.