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When Diane Papazian's husband, Harry, pestered her to add Troy, a 4-month-old Doberman pinscher , to the family, she was reluctant. They already owned a fox terrier, and besides, she had allergies . Little did the resident of New York's Staten Island know, the new dog would be what she called her "lifesaving puppy," detecting stage two breast cancer even though she had gone for a mammogram only six months earlier.
Related: Four Reasons Why Having a Dog Is Good For Your Health 
You could see Troy all grown up and competing in the recent Westminster Kennel Club Dog Show . Besides being a hero, he's currently the ninth-ranked Doberman pinscher in the country and number one in the state of New York and has done training to be a therapy dog in his postshow career. What did you do today?
The story begins three years ago when Troy's breeder asked if the family could take him home a month earlier than expected. "He was a tiny little thing," Papazian, now 56, told Yahoo! Shine. "One night he was curled up between us in bed. He kept nuzzling up against my left side." Troy's persistent nosing triggered an allergic reaction. "I itched myself, and then I popped up in bed and said, 'Holy cow! What's this?'" She felt a lump in her left breast that was already three centimeters in diameter.
Papazian alerted her physician, who determined that the lump was malignant, and started treatment. To combat the aggressive form of breast cancer she was suffering from, she had a double mastectomy and began chemotherapy. While she is still on chemo, Papazian said she is now cancer-free and feeling "very healthy." She added, "If the dog had come a month later or if we hadn't taken him, I don't know what would have happened."
While Troy's incredible nose seems nothing short of a miracle, there is a growing field of research studying dogs and disease detection . Because dogs' sense of smell is so sharp — 1,000 to 100,000 times more acute than human's, depending on the breed — they are able to detect subtle chemical changes in the breath, blood, and urine  that can be indicators of disease. They can sniff out volatile compounds  in the body that may indicate the presence of cancerous cells.
Sheila O'Brien of the Guide Dog Foundation  told Yahoo! Shine that many organizations are doing work with what are called "trained scent-discrimination tasks" in the area of canine disease detection, with successful results. She explained how dogs can also alert owners with diabetes to an oncoming attack of low blood sugar. Speaking with the New York Daily News , Dina Garbis, a researcher with the InSitu Foundation , a nonprofit studying cancer detection and dogs, said, "Dogs can with 98 percent to 99 percent accuracy . . . tell you whether volatile, organic compounds are present in blood or breath samples."
Troy is now an imposing 86-pounder with an intense and steady gaze. Papazian said, "People get scared of Dobermans, but he's got the sweetest personality." He faced off against nearly 3,000 blue-ribbon pooches from around the globe at Westminster, but she and her husband already call him "the best dog on the planet."
— Sarah B. Weir
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