When Diane Papazian's husband Harry pestered her to add Troy, a four-month-old Doberman Pinscher, to the family, she was reluctant, they already owned a fox terrier, and besides, she had allergies. Little did the Staten Island resident know, the new dog would be what she calls her "life saving puppy," detecting stage two breast cancer even though she had gone for a mammogram only six months earlier. You can see Troy all grown up and competing in the Westminster Kennel Club Dog Show next week. Besides being a life-saving hero, he's currently the ninth ranked Doberman pinscher in the country and number one in the state of New York and is training to be a therapy dog. What did you do today?

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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," Papazin, now 56, tells 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.

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Papazin alerted her physician and started treatment. To combat the aggressive form of breast cancer she was suffering, she had a double mastectomy and began chemotherapy. While she is still on chemo, Papazian says she is now cancer-free and feeling "very healthy." She adds, "If the dog had come a month later or of 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-1000 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 the volatile compounds in the body that may indicate the presence of cancerous cells or alert owners with diabetes to an oncoming hypoglycemic episode.

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Troy is now an imposing 86-pounder with an intense and steady gaze. Papazian says, "People get scared of Dobermans, but he's got the sweetest personality." He'll be facing off against nearly 3000 blue ribbon pooches from around the globe at Westminster, but the she and her husband already call him, "the best dog on the planet."

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