A paedophile doctor who abused young cancer patients has been sentenced to 22 years in jail.
Myles Bradbury, 41, of Herringswell in Suffolk, admitted abusing 18 children in his care at Addenbrooke's Hospital in Cambridge, between 2009 and 2013.
Bradbury has admitted 25 offences, including sexual assault, voyeurism and possessing more than 16,000 indecent images.
The judge told him his offences were a "gross and grotesque breach of trust".
Sentencing him at Cambridge Crown Court, Judge Gareth Hawkesworth said: "In many years' experience on the bench, I have never come across a more culpable or grave course of sexual criminality which has involved such a gross and grotesque breach and betrayal of your Hippocratic Oath and trust reposed in you by your patients, their families and colleagues."
Bradbury's actions amounted to a "prolonged, carefully planned, cruel and persistent campaign of abuse" he said.
The judge told Bradbury, a blood cancer specialist who was arrested in December 2013, he had no doubt he had caused psychological harm to his victims and was at risk of doing so in future.
A victim's account of an examination by Dr Bradbury
"He would ask to get me in the room on my own, and say I'm old enough to go in a room on my own.
"And then he'd want to check me.
"Instead of checking just my joints, he'd want to check my whole body.
"He'd make me strip down.
"He focused on my private parts."
Canadian authorities had alerted the UK's Child Exploitation and Online Protection Centre (Ceop) in July 2012 that Bradbury had bought a DVD containing indecent images of children, but Ceop did not pass on the information until November 2013.
In September, he pleaded guilty to six counts of sexual assault and 13 counts of engaging in sexual activity with a child.
Bradbury also admitted three counts of causing or inciting a child to engage in sexual activity, one count of voyeurism and two counts of making indecent images of a child.
By Julian Sturdy, BBC East investigations editor
He was a charming intellectual with a grotesque secret.
Myles Bradbury hid his depravity from everyone. No-one suspected a thing - not even his wife, his hospital colleagues or worshippers at his local church.
But the consultant also fitted the profile of a paedophile - someone who goes out of his way to get access to children. His choice of profession, and his decision to work in an African AIDS orphanage.
He's lost a £100,000 career, his wife has separated from him, taking their new child with her.
He only answered "no comment" in police interviews. So we may never know how many boys he molested.
His greatest claim to fame was that he once met the Queen. Now he will be detained at her pleasure for a very long time.
Bradbury had used a spy pen to take pictures of his victims.
It contained 170,425 images of "boys partially clothed... none indecent", the court heard.
The images of his victims, some of whom had haemophilia, leukaemia and other serious illnesses, were gathered at Addenbrooke's Hospital.
The hospital's chief executive, Dr Keith McNeil, 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."
As well as sentencing him to 22 years, Judge Hawkesworth said Bradbury would be placed on the sex offenders register for life and also made subject of a sexual offences prevention order for life.
Bradbury must serve half his prison sentence before being released on licence, the judge said.
The Crown Prosecution Service for the East of England (CPS) described Bradbury's abuse of his patients as "one of the worst cases of a breach of trust" it had prosecuted.
Michelle Brown, head of the CPS Rape and Serious Sexual Offences Unit (RASSO), said: "This paedophile doctor took advantage of his young patients battling serious illness by systematically sexually abusing them. Such cruelty is unimaginable to most of us."
Det Supt Gary Ridgway, from Cambridgeshire Police, said: "This case has understandably caused distress to many people.
"Bradbury was highly respected and revered by the families of his victims who trusted him implicitly but he betrayed that trust in an appalling way, by carrying out examinations purely for his own sexual gratification."
Reacting to the sentence, the parents of one victim said: "We're very happy... it may be over for him but it's not for us."
Another mother said: "I'm very pleased - he's got what he deserved."
Mr Ridgeway paid tribute to the victims and their families, saying they showed "great bravery in coming forward and ensuring Bradbury was held to account".