The King could be suffering from early bladder cancer, according to a health expert, following his diagnosis with 'a form of cancer' - days after he returned from hospital after receiving treatment for benign prostate enlargement.

According to Professor Robert Thomas, who is a full-time NHS Consultant Oncologist at Addenbrooke's and Bedford Hospitals, the most likely diagnosis is early bladder cancer, which may involve the urethra - the tube which carries urine through the prostate. This form of cancer is sometimes detected during prostate treatment.

He said: "The urethra has cells similar to the bladder. Treatment would be surgical removal via a cystoscopy - although this may have been done already. If the tumour has not spread into the muscle of the urethra or bladder wall, a diluted chemotherapy is usually injected into the bladder once a week for six weeks - this causes cystitis but prognosis is usually very good - although of course we do not have all the details - this would explain why they say no duties for six weeks."