MARY LOUISE KELLY, HOST:

King Charles III has cancer. Fewer than 18 months into his reign, the British monarch is suspending public duties. But Buckingham Palace says he will continue with the paperwork of state business as he undergoes outpatient treatment. And that treatment began today in London. That is where NPR's Lauren Frayer is based, and she joins us from our studio there. Hey, Lauren.

LAUREN FRAYER, BYLINE: Hi, Mary Louise.

KELLY: Tell us more about the king's diagnosis and his prognosis.

FRAYER: We actually don't know what type of cancer it is. King Charles was hospitalized recently for an enlarged prostate. That condition was benign. But Buckingham Palace says in the course of that treatment, another, quote, "separate issue of concern" was noted and that subsequent tests have identified a form of cancer - no word on what type or what stage. The palace says the king today began treatment and that he remains, quote, "wholly positive." So while he will postpone public duties, he's expected to continue meeting weekly with the prime minister, for example. He'll keep getting those red boxes. They're called ministerial or despatch boxes - literally red, wooden boxes with government documents in them. He gets those daily, and he's expected to continue to do so throughout his treatment.

KELLY: Yeah, I remember those red boxes from the "The Crown" - too many hours of my life...

FRAYER: Yeah, "The Crown."

KELLY: ...Spent watching "The Crown" on Netflix...

FRAYER: Exactly.

KELLY: ...All the red boxes. I want to follow up on what - on just practically what this means because as king, he's a celebrity, but he also plays a key constitutional role in the U.K. What happens when he suspends public duties?

FRAYER: He does. So the king's role is ceremonial, but, as you say, it's important. And there are longstanding protocols in place for this. The King's private secretary is in touch with the private secretaries of the prime minister and that of the Cabinet office. If the king is incapacitated, Counsellors of State are appointed to act on his behalf, but the palace has indicated that those are not required at this point. Now, if that changes, Queen Camilla could step in as a Counsellor of State. So could the next four adults in line for the throne. So that would be the king's two sons, Prince William and Prince Harry, then the king's brother and then his eldest child, the king's niece.

KELLY: And just to emphasize, as king, he is head of state, right?

FRAYER: He - yeah, totally. And so that really comes into play during elections. And the U.K. is expected to hold an election by the end of this year. The King has a big role in that. He dissolves Parliament. He appoints a new prime minister to form a new government. Counsellors of State could possibly do that for the king, but it would have to be with his explicit permission and authorization.

KELLY: I'm thinking, Lauren, this comes, of course, a year and a half after the royal family and the U.K. lost Queen Elizabeth II. What has been the reaction to this announcement there in Britain and internationally?

FRAYER: Yeah. So the news came after sundown here, after the working day was over. But already, condolences are pouring in. President Biden has said he's concerned about King Charles. Former President Trump called the king a wonderful man. The U.K. prime minister, Rishi Sunak, says the whole country wishes him well. I mean, Charles waited sort of all of his life to become king. He was 73 when his mother, Elizabeth II, died. He's the oldest person ever to ascend the throne here. So there's sympathy that he's facing a health challenge, you know, so soon after taking the throne.

KELLY: And have we heard from the rest of the royal family? I'm thinking in particular about the king's sons.

FRAYER: Yeah. So the King personally notified his siblings as well as his children about his diagnosis. Prince Harry, you'll recall, quit royal duties back in 2020 and is now based in California with his American wife, Meghan, the Duchess of Sussex. He is actually en route to London to be with his father right now. It's also a difficult situation for Prince William, Harry's brother, especially because his wife, Kate, is currently recovering from abdominal surgery. She was hospitalized recently for two weeks - in fact, in the same London hospital where the king had his prostate treatment. And so William, the heir to the throne, has been nursing his wife and now has this news of his dad's diagnosis.

But as you know, Mary Louise, the Brits have this slogan. Keep calm, and carry on. And it's an emotional time for the royals here, but it will also increase their workload, at least for some of them, as Queen Camilla and as Prince William and others take on more of the public duties while the king is undergoing this treatment.

KELLY: That is NPR's Lauren Frayer, keeping calm and carrying on in London. Thank you.

FRAYER: Will do. Thanks. Transcript provided by NPR, Copyright NPR.