By Fergus Walsh
BBC News medical correspondent
Dr Nick Plowman says the cyberknife can target cancer cells with 'high exactitude'
A robot radiotherapy machine to treat cancer is to be available in the UK for the first time from February.
Called the Cyberknife, it moves with a patient's breathing so tumours can be targeted with greater accuracy, and damage to healthy tissue is reduced.
The machine will be at the private Harley Street Clinic in London.
More than a dozen countries worldwide already use the machine, including France, which has three under clinical trial.
At first sight the Cyberknife looks like one of those robots used in the TV car commercials.
It is a compact linear accelerator mounted on a robot arm.
The cyberknife minimises damage to healthy tissue
The cyberknife works by delivering multiple beams of high dose radiation from a wide variety of angles using a robotic arm.
X-ray cameras monitor the patient's breathing and re-position the radiotherapy beam in order to minimise damage to healthy tissue.
This accuracy enables tumours to be treated that are in difficult or dangerous to treat positions, such as near the spinal cord.
The French National Cancer Institute has paid for three Cyberknife machines to be trialled at hospitals in Nice, Nancy and Lille.
Professor Eric Lartigau from the Centre Oscar Lambret in Lille said he was very impressed.
He said: "We have treated just over 200 patients in 18 months and all couldn't have been treated with conventional radiotherapy so it is a big plus for our patients."
One of those patients is Helen O'Doherty from Limerick in Ireland.
She has liver cancer and was told by her doctors that conventional treatment, like surgery, was not possible, so she was referred to Lille for radiotherapy with the Cyberknife.
The Irish health service is paying for her treatment and she has made several trips to Lille with her husband.
Professor Eric Lartigau is impressed by the technology
She said: "I feel very privileged and excited to be here because I know it's the best and I'm so grateful to have another chance."
Conventional radiotherapy involves twenty or more short sessions with low-dose radiation.
But because the Cyberknife can deliver high dose beams with greater accuracy, it means Helen can have all her treatment in just three sessions.
Fifteen countries including the USA, Germany, Italy and Japan have the Cyberknife.
It is also installed in hospitals in Vietnam, Turkey and Greece.
In early February, the first Cyberknife in the UK will begin treating patients at the private Harley Street Clinic in London.
Clinical director Dr Nick Plowman, who is also a consultant oncologist at Barts Hospital, does not believe that Britain is lagging behind.
He said: "It is only in the past couple of years that the software has got to the stage where we believe it is right for introduction to our clinical service.
"So we don't believe we have been tardy; we have been waiting for the improvements to come and now they're here we are happy to introduce the machine."
Treatment will cost between £20,000 and £25,000.
Although most will be private, the clinic says it expects to treat some NHS patients.
Dr Plowman is keen to stress that conventional radiotherapy works well for most patients.
But for patients with some hard to treat tumours the Cyberknife will present another potential therapy.