Man's best friend has nose for cancer

Dogs may be able to smell cancer according to research malehealth has sniffed out at Amersham Hospital in Buckinghamshire.

Cancers have long been thought to produce distinctive odours and, after training, six dogs of varying breeds were able to detect bladder cancer in a patient's urine in 41% of cases. Not a fantastic strike rate but a lot better than the 14% that could be expected by chance alone.

Certainly it was good enough to convince a stats expert who wrote in the British Medical Journal where the research appeared: 'The study was carefully designed to include several features to minimise bias, and it is hard to fault the study in this respect. On balance the

results are unambiguous. Dogs can be trained to recognise and flag an

unusual smell in the urine of bladder cancer patients.'

There have been many stories in the past of dogs apparently detecting cancer. Researchers wrote a to The Lancet in the 80s about a woman who visited a doctor because of her dog's obsessive interest in a skin lesion. It turned out to be cancer. The BBC report that similar anecdotal claims have been made about cancers of internal organs like the breast and lung.

Of particular interest is the fact that all of the dogs indicated one of the "bladder cancer free" samples as positive. Concerned by the dogs' behaviour, the doctors did further tests and discovered a tumour in the patient's right kidney.

Dog lovers may be interested to know that the three cocker spaniels did best in the research while the mongrel did worst. Some patients' bladder cancers were noticeably easier to detect in their urine than others raising interesting questions about the strengths of cancer's smell. Dried urine worked less well than the wet stuff!

Lead researcher Dr Carolyn Willis said: 'We are very excited because this is the first time this has been scientifically proven. Dogs have these fantastic olfactory abilities. They are recognising a signature smell of cancer which is very difficult to pick up by any chemical methods. They are not just detecting a single chemical. They were having to pick out smells for bladder cancer amongst the hundreds in urine and that's no mean feat."

Before you enroll young Shep in medical school, this doesn't means your local hospital will be recruiting spaniels anytime soon. Researchers are more interested in identifying the exact combination of chemicals and designing a medical device to smell them in patients.