The Duke of Cambridge has hailed the "incredible" workof two surgical teams as he watched live operations at one the Royal Marsden in Chelsea.
Dressed in medical scrubs, he spent around 10 minutes viewing a breast reconstruction procedure for a female patient in her 80s.
As he was greeted by lead surgeon, Mr James, William said: "It's slightly surreal meeting you in this situation."
The Duke looked into a micro-vascular microscope placed above the body as he was talked through the surgical procedure, which usually takes six to eight hours to complete.
"That's amazing," he said as he peered through the microscope.
William is the first royal to view surgery at the Royal Marsden,which is a world-leading cancer centre specialising in all areas of diagnosis,treatment, care and research into the disease.
He has been president of the hospital trust since 2007, a position previously held by Diana from 1989 until her death in 1997.
More top news
One of the teenagers was left so badly burnt doctors say he may lose his eyesight.
Jame Murray's challenge is to deliver Mr Khan's manifesto pledge to build more than 50,000 new homes a year - half of them affordable.
Ryan Lee was removed from the finishers' list because he was not picked up by the 5k checkpoint.