The King met chemotherapy patients and had a go on a robot that is used in surgery during a visit to a hospital.
Charles, who is still receiving treatment for an undisclosed form of cancer, was shown a type of robot system that is used in surgery by Professor Ben Challacombe at Guy’s Cancer Centre on Monday.
He also unveiled a plaque marking the 300th anniversary of Guy’s Hospital, met doctors and nurses and was briefed on research projects at King’s College London Innovation Hub.
The Da Vinci surgical system includes arms with instrument holders and a camera holder that are controlled through the use of a console, Charles was told.
It enables quicker recovery, fewer scars and less pain, the King heard.
Charles then had a go at the console himself, sitting at a stool, looking through a screen to get a 3D view and using the tools to try to direct the robot, joking: “I think I need more practice.”
Meanwhile, a £5 note showing Charles’s face was placed on the table to show how far the machine could zoom in.
Prof Ben Challacombe told the King: “We’ll have to get you back for a full immersive course.”
Charles asked: “And less invasive, you said?”
Prof Challacombe replied: “Yes, much quicker recovery.”
The King was presented with a book on the history of Guy’s Hospital by Professor Stephen Challacombe, Professor Ben Challacombe’s father.
Charles said: “It must’ve taken an awful lot of research”, and Prof Challacombe replied: “We had intended it to be 300 pages, it’s now 500”.
The King joked it was “a little light bedtime reading”, before thanking him and joking about how “frightfully heavy” it was.
After arriving at a laboratory in the centre’s innovation hub, the King, who is patron of King’s College London, was briefed on King’s College London and Guy’s cancer research projects.
The King’s College London Innovation Hub brings cancer research and patient treatment under one roof. Scientists analyse samples from patients being treated in the chemotherapy village on the floor below to develop personalised treatment.
The King asked lots of questions in the laboratory about what he was being shown.
He was told how they now use AI in their work with cancer, and the King asked: “What proportion of the time is it right? Because it’s not always right.”
Charles then visited the chemotherapy village and met patients having treatment.
The King met David Coleman, 77, who is on a new immunotherapy drug, and joked to Charles that he was “a guinea pig” and they had a laugh together.
Graham Peiser, 69, told the King it was a “world-class facility”.
The King then unveiled the plaque, which was met with applause and cheers.
Crowds of people gathered while Charles unveiled the plaque, taking photos, and then the King went over to speak to them both inside and outside the hospital afterwards.
After meeting the King, Mr Peiser, from Blackheath, said: “It was a very nice chat. And very, very nice to meet him.
“A huge surprise. I come here once a week and the chances of being here on this day on this particular unit.”
After they met, Mr Coleman, from Sidcup, said the King “put you at ease straight away”.
Prof Ben Challacombe said after the visit: “He was very interested in what this could do in terms of improving outcomes for patients.
“So I told him about decreased pain and scars and decreased length of stay, and he actually used the phrase to me, ‘this seems much more minimally invasive than the surgery that I’ve previously heard of’, which was nice.”
He added: “I could see he was speaking from the point of view of having been through treatment himself.”
Charles was diagnosed with cancer at the age of 75 and less than a year and a half into his reign.
The disease was discovered while he was having a corrective procedure for a benign enlarged prostate, for which he spent three nights in hospital.
Buckingham Palace, announcing the news in February 2024, described it as a “form of cancer” but said it was not prostate cancer.
In December 2025, in a message to the nation as part of Channel 4’s Stand Up To Cancer night, the King revealed the “good news” that “thanks to early diagnosis, effective intervention and adherence to doctors’ orders”, his treatment was being reduced in the new year.
Charles has been receiving cancer treatment as an outpatient since early February 2024.
