By Liz Bestic AT 8 o’clock every morning, Ollie leaves his house and sets off on the short drive to work at the local laboratory. Eager to get to going on his latest project, he greets his colleagues enthusiastically before donning his regulation lab coat and heading for the testing room. Here, Ollie begins his tour of a carousel which has small phials of urine attached to each arm. His job is simple – to take a gentle sniff of each one and let his boss know which of the samples contains a particular type of cancer. It is precise work, but Ollie gets it right over 90 per cent of the time. Not bad for a Labrador. Diagnosing cancer is a hit-and-miss affair. Often the symptoms that prompt a visit to the doctor only emerge when a cancer is relatively advanced. Screening only works for some types of cancer, and diagnostic tools are often unreliable or invasive. Better detection methods are badly needed. The nose knows (Image: Digi_Guru/Getty) Video: Dogs sniff out cancer using smell alone Now it seems that dogs could catch a whiff of cancer at an early stage, because of small chemical changes that take place within diseased cells. These chemical signatures are excreted in breath and urine, which dogs like Ollie, at the Medical Detection Dogs charity in Milton Keynes, UK, are being trained to detect. Stories of dogs alerting their owners that they have cancer have been emerging for decades, but will the idea live up to scientific scrutiny? Could dogs be used to save lives?