Can Dogs Smell Cancer?

Does cancer have an odor? Pet owners tell amazing stories of dogs sniffing out disease and saving their lives

I have an interesting story about this. I used to do dog rescue volunteering with a friend. She is a nurse. One day, she asked me to smell a dog. She wanted me to compare the smell of one dog compared to other dogs of the same breed on her property. 

 

This one dog had a bad smell. The other dogs, all unrelated but of the same breed, had a different but common scent. My friend said that human cancer patients had a bad smell like this dog, and she wondered if this dog had cancer. 

 

I have never forgotten this and sometimes I sniff a dog as a clue to if a dog might have a medical problem.