Hopes that man's best friend could help doctors in detecting prostate cancer received a boost with research suggesting that trained German shepherd dogs could sniff out the chemicals linked to the disease from urine samples with remarkable accuracy.
The reliability rate reported by an Italy-based team in the Journal of Urology comes from the latest of several studies extending back decades and raises the prospect that the sense of smell of canines could help doctors in the identification of several human cancers and infectious diseases.
The two female dogs sniffed urine samples from 900 men, 360 with prostate cancer and 540 without with accuracy of well over 90 per cent in most cases.
The paper's authors, from the Humanitas Clinical and Research Centre in Milan and other institutes, admitted further work was needed in determining just how valuable could be the dogs' skill in identifying, the signs of prostate cancer in daily practice.
Prostate cancer is the most common type of the disease in British men, with 40,000 new cases reported every year.
Among the questions that remained unanswered was what it was the dogs actually smelled and whether this was a single odour or those from a mixture of chemicals.
The Italian study backed up tests carried out by Buckinghamshire charity Medical Detection Dogs.
According to Medical Detection Dogs' co-founder Dr Claire Guest, its own research had found a 93 per cent reliability rate when detecting bladder and prostate cancer, and described the new findings as "spectacular" www.southwalesguardian.co.uk reported.
The latest research by the Department of Urology at the Humanitas Clinical and Research Centre in Milan involved two German shepherds, one of whom got it right in 98.7 per cent of cases, while the other dog identified correctly in 97.6 per cent of cases.
According to the researchers, the dogs were able to detect prostate cancer specific volatile organic compounds in the urine but said an important question remained as to how a dog would find it in daily practice.
Dr Guest said the results were spectacular and offered further proof that dogs had the ability to detect human cancer.
She said it was particularly exciting that such a high rate in detection of prostate cancer had been demonstrated given that the existing tests were woefully inadequate.
According to her, there was currently a "reluctance to embrace this tested, time-old technology" but dogs could pick up a scent in a dilution of one to a thousand parts.