Diane Papazian, from New York, says Troy persistently nuzzled into her breast when he was just a four-month-old puppy.Mrs Papazian then realised Troy was showing an interest in a lump and decided to go for a mammogram - despite having had one just six months earlier.As a result, she was diagnosed with aggressive breast cancer.Mrs Papazian, 56, went on to have a double mastectomy and chemotherapy and is now cancer-free.Troy, a show dog, is currently the number one Doberman in New York State and ranks ninth in the U.S.He has also been nominated by the American Humane Association for the Hero Dog of the Year award.Mrs Papazian, who is married to 57-year-old Harry, said: ‘I'm very grateful for Troy - not only is he an amazing and compassionate dog, but he saved my life.‘During my recovery, having him around kept my mind occupied and he would just sit by me and look at me with his big brown eyes full of love.‘Troy thinks he is a lap dog and follows us around and wants to be with us all day. He is kind, loving, protective and gentle. He actually lets us hug him and graciously accepts our kisses.‘It is even more meaningful for people to hear this story now, as I am healthy and cancer-free and Troy is being acknowledged for the amazing, lifesaving puppy he is. We are so proud of him.’Mrs Papazian is also grateful to her husband as it was he who persuaded her to add Troy to the family - even when she argued that they already had one dog and that was enough.Troy led to her discovering a lump in her breast as he kept nuzzling into her left side and caused an itchy allergic reaction.It was when she itched the rash that she found a 3cm lump in her breast.A dog's sense of smell is thought to be about 100,000 times more powerful than that of a human and numerous studies have shown they can detect signs of cancer.A study by the InSitu Foundation in 2003 found that dogs can sniff out lung and breast cancer by smelling a patient's breath.Then, in 2004, a study by Buckinghamshire Hospitals Trust and the charity Cancer and Bio-detection Dogs, found the pets can also detect bladder cancer in urine samples.In January 2011, a study published in the British journal Gut said that a specially trained eight-year-old black Labrador retriever named Marine had detected colorectal cancer 91 per cent of the time when sniffing patients' breath, and 97 per cent of the time when sniffing stools.Cancer cells are known to produce chemicals called volatile organic compounds which give off distinct odours which dogs are believed to react to. Lung and breast cancer patients are known to exhale biochemical markers which can be traced to tumours that exude substances not found in healthy tissue.As a result, dogs can be trained to point their nose at sample pots they believe are cancerous.Trained dogs have also picked up melanomas by sniffing skin lesions.However, it is not only trained dogs that have detected cancer.There are many examples of people being diagnosed with the disease after being alerted to it by their pet dogs.(dailymail.co.uk)ANN.Az