How much does the public have a right to know about King Charles’ cancer diagnosis?

Britain’s King Charles III was seen on Tuesday for the first time since the bombshell announcement of his cancer diagnosis, as questions swirl over the exact nature of his condition.

The unexpected disclosure from Buckingham Palace dropped on Monday evening. It revealed the monarch had already started treatment for an unspecified cancer that was identified while he was being treated separately for an enlarged prostate.

Charles, 75, is stepping away from public-facing duties during his outpatient treatment on the advice of doctors, but the palace stressed that he would continue state duties and paperwork.

“He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible,” the palace said.

It added that the King had opted to disclose his diagnosis “to prevent speculation and in the hope it may assist public understanding for all those around the world who are affected by cancer.”

While the British monarch has been unusually forthright about his health, much more so than his predecessors, the palace statement has triggered a storm of speculation and debate about exactly how much the public has a right to know.

The particular type of cancer was not revealed, and no further details are expected at this stage. Prostate cancer has been ruled out to CNN by a royal source, who did not provide any further detail.

UK Prime Minister Rishi Sunak Tuesday appeared to go further than the palace had while speaking to the BBC. Sunak said he was “like everyone else … shocked and sad” but that the King’s diagnosis had been “caught early.”

But when asked for clarification afterward, Sunak’s spokesman told reporters that the prime minister appeared to have been going off the palace statement, which noted “the swift intervention” of the King’s medical team.

CNN understands that Sunak was informed of the King’s condition prior to the public announcement – as were Charles’ siblings and children, whom he told personally.

Royal experts and commentators have said the household’s intentions were candid, noble and well-meaning but that the resulting gray space has left people concerned.

“It is uncharted waters. We don’t know what cancer he has or what treatment he is having, but also how long he’s going to be out of action for,” said CNN royal historian Kate Williams.

In the 48 hours since, there has been an outpouring of good wishes both at home and abroad. US President Joe Biden led messages of support from world leaders. He said on social media that the King was in his thoughts.

“Navigating a cancer diagnosis, treatment, and survivorship takes hope and absolute courage,” the president wrote. “Jill and I join the people of the United Kingdom in praying that His Majesty experiences a swift and full recovery.”

Many of the UK’s cancer care charities have also shared encouraging words, including Macmillan Cancer Support, which added that it hoped the King’s openness would encourage the public to get checked. Charles has been the patron of the organization since 1997.

According to Cancer Research UK, around 375,000 new cancer cases are diagnosed in the UK each year. Macmillan Cancer Support estimated in 2022 that there were around 3 million people living with cancer in the UK, predicting that this would rise to 3.5 million by 2025.

Health experts suggest it is not uncommon for cancer patients to be diagnosed when seeking imaging or medical care for other reasons.

“You’re going in for one thing, but then you do additional testing — either as part of a general evaluation or influenced by certain symptoms or signs or blood tests that trigger a procedure or imaging — which then leads to the diagnosis of cancer in a different organ system,” said Dr. Anil Rustgi, director of the Herbert Irving Comprehensive Cancer Center at NewYork-Presbyterian/Columbia University Irving Medical Center, who was not involved in Charles’ medical care.

“A lot depends on what type of cancer and what stage it’s at, but sometimes with early-stage cancer, there are no symptoms,” Rustgi said. “And it’s either detected at the time of screening or incidentally.”

While the palace may not have wanted a frenzy to erupt around the King’s diagnosis, the absence of specifics meant it was somewhat inevitable. Royal biographer Sally Bedell Smith said it is “always tricky to release a partial picture” because people can interpret or over-interpret.

She said times were “very different,” referring to the health battles fought by the King’s grandfather.

“Harking back to his grandfather, George VI, who had arteriosclerosis which was not fully explained to the public and then of course he had lung cancer, and his left lung was removed. The doctors never said it was cancer. They said they had to do it to repair some structural defects,” she said. “They didn’t tell the family; they certainly didn’t tell the public.”

With unanswered questions about what Charles is facing, the public are trying to fill in the gaps. Seeing Prince Harry appear to drop everything and fly to London to visit his father, knowing that relations between the pair have been strained over the past several years, has suggested a sense of urgency to some.

But royal experts said there are positive signals that shouldn’t be overlooked. Emily Nash, royal editor at Hello! magazine, told CNN: “If the palace makes the move to appoint the counsellors of state, people might feel their concern rising for His Majesty. These are members of the family who can deputize for him in constitutional affairs if he’s incapacitated or if he’s overseas on other duties. It’s been made very clear to us so far that there’s no plan to bring any of these people into play.”

Two counselors can be appointed to act on the monarch’s behalf through what’s known as a letters patent and help keep the state ticking over. The list of royals who can step in includes Queen Camilla, Princes William, Harry, Andrew and Edward, as well as Princesses Anne and Beatrice. However, it is unlikely Andrew or Harry would be called on as they are no longer working royals.

Nash said it was “very reassuring” that the palace wasn’t looking to install any counselors at this point.

“It really speaks volumes about the King’s determination to continue carrying out his role as best as he can at the moment,” she said. “That means the privy council meetings, the audiences with the prime minister, his red boxes, signing his assent on legislature – these are all key parts of his role that are not public facing so he can continue to do these behind the scenes.”

The developments of the past few days have reignited a debate over how much the public deserves to know the health of its head of state.

Many feel the family should be more transparent and that the public is entitled to more information as the royal household is taxpayer-funded. Some assert that the public has a right to know because the royals are public figures and personal freedoms are inevitably compromised when representing crown and country. Others argue that by not disclosing the exact cancer, they are inadvertently fueling the gossip.

The public is also aware that the Princess of Wales, who recently underwent abdominal surgery, is still recovering at home in Windsor. She’s not expected to return to engagements until at least Easter. While the public knows her operation was successful, it hasn’t been revealed exactly what it was for. Kensington Palace has been fiercely protective of her, with aides aware of how popular she is while wanting to offer the 42-year-old some privacy.

“This is what the royals have been wrestling with throughout the 20th century, ever since they let cameras into the coronation of the Queen – how much information to give,” Williams said. “I think, eventually, the King will tell us what cancer it is he has been suffering.”

Historically, specific medical conditions were rarely disclosed to the public. Palace aides would say the family members are entitled to a degree of medical privacy despite their positions as public servants. However, the situation changes when their condition affects their ability to perform public duties. At that point, the palace has a duty to reveal what is going on, which is why a statement was issued on Monday evening.

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Kristina Kyriacou, a former communications secretary to the King, touched on the palace’s approach during an appearance on ITV’s “Good Morning Britain” show on Tuesday. “I have to say, I wouldn’t open the door more. They’ve said a form of cancer has been found, and I personally wouldn’t have advised you go further and say what type of cancer. I think there’s plenty of time for that.

“The trouble is, the more information you give, the more people speculate. The second they know what kind of cancer it is, everyone starts looking it up, people start Googling,” she continued.

Kyriacou said she’d interpreted the palace statement positively and to mean that the condition is treatable.

“I hope I’m right. We should remember at this point, the monarchy are trying not to become the story; I know that’s being a bit laughable for certain members of the royal family in the past couple of years. But Queen Elizabeth and King Charles, they do not want to become the story, they still want to serve their public. In the fullness of time, I would like to think King Charles will talk about his treatment.”

Meanwhile, Estelle Paranque, an expert in royal studies and Associate Professor in Early Modern History for Northeastern University London, suggested the type of cancer the King is facing is somewhat irrelevant.

“I don’t think we need to know what type of cancer he has or at what stage. I think we need to know how the royal duties will be handled and by whom and they need to inform us of a plan if things get wrong for the king but apart from that he has a right to privacy. Being diagnosed with cancer is very life-changing. He should be able to handle it the way he needs to.”

The historian added that the palace’s moves on Monday show that Charles wants a more modern monarchy. “He is compromising by revealing the outcome of his medical appointment but he is not revealing everything to keep his privacy safe and that is a smart move,” she said.

CNN’s Catherine Nicholls, Jacqueline Howard and Claudia Rebaza contributed reporting.