A children's doctor who sexually abused 18 boys in his care has been sentenced to 22 years in prison.
Dr Myles Bradbury carried out examinations on children "purely for his own sexual gratification" and with no medical justification, Cambridge Crown Court heard.
The cancer specialist admitted 25 offences in September involving 18 boys aged 10 to 16 whom he had treated while working as a paediatric haematologist at Addenbrooke's Hospital in the city.
The abuse included seven counts of sexual assault and 12 of engaging in sexual activity with a child.
Sentencing him, Judge Gareth Hawkesworth said: "For a doctor to attack children in this way is one of the worst forms of sexual abuse imaginable."
"These boys were all vulnerable and gravely ill. In all my years on the bench, I have never come across such a grotesque betrayal of your Hippocratic oath."
The judge said Bradbury's sentence would be reduced because of his early guilty pleas, although "some might observe" that the weight of evidence meant he had little option but to admit the offences.
Victims' lawyer Renu Daly said the families were "relieved" that Bradbury had been given a lengthy jail term as it meant he would be unable to harm more children.
His victims included children with haemophilia, leukaemia and other serious illnesses, some of whom have since died.
Bradbury, a married 41-year-old father-of-one from Herringswell, Suffolk, would abuse the boys on occasions when "the parent was a curtain away".
He would also secretly film them using a camera pen, and more than 16,000 images were found on a disc at his home.
Bradbury was described as "a man of great charm and persuasiveness" whom everybody trusted.
When one victim raised concerns with his mother, she said: "He's a doctor, it must be necessary."
Prosecutor John Farmer said Bradbury had a "longstanding, unlawful, sexual interest in boys" and abused them "for his own personal gratification".
The Crown Prosecution Service in the East of England said it was "one of the worst" cases of a breach of trust it had ever prosecuted.
Bradbury's barrister, Angela Rafferty, said in mitigation that his guilty pleas had spared his victims the ordeal of having to give evidence.
Bradbury accepts that what he did was "repugnant", Ms Rafferty told the court.
The offences were carried out over four-and-a-half years from 2008.
Bradbury's crimes came to light in November 2013 after an 11-year-old told his grandmother about what had happened during a visit and how he had been told to keep it a secret.
Bradbury was suspended by Addenbrooke's before being arrested the following month.
Dr Keith McNeil, chief executive of the Cambridge University Hospitals Trust, said: "Our thoughts today are with our patients and families who were victims of Bradbury's shocking and cynical abuse.
"Today's sentencing of Bradbury cannot undo the damage he caused but he is finally behind bars and is no longer a risk to vulnerable children.
"The lengthy sentence shows Bradbury's abhorrent betrayal and manipulation of his position as a doctor has been fully recognised."
