Colleen Ferguson's German Shepherd Inca persistently sniffed her breath, leading her to seek medical help. She was diagnosed with stage one lung cancer after a scan revealed a golf ball-sized tumor in her left lung. She underwent surgery to remove the tumor in June 2015 with no additional treatment required.
In a similar case, Katie Banfield's cocker spaniel Alfie sniffed intensely at one part of her breast, leading to her seeking medical attention. 5cm x 2cm lump in the same spot Alfie sniffed. Katie Banfield has now been given the all-clear from cancer.
Her behaviour towards me changed, she just started homing in on my mouth. Every time she could get a sniff of my mouth she would frown.
These cases align with the work of Medical Detection Dogs (MDD), an organization that trains dogs to detect the odour of human diseases like cancer, Parkinson's, and malaria. Dogs can smell odour at parts per trillion, equivalent to a teaspoon of sugar in two Olympic-sized swimming pools. Katie Banfield is doing a tandem sky dive in July to raise money for Medical Detection Dogs.
Despite these successes, scientific unknowns remain about canine cancer detection mechanisms and reliability.
She just had this focused intent on my mouth, and you couldn't push her away until you had done an outbreath. When she got that she would give me such a look and walk away.
In no way did I expect lung cancer at all. It was such a shock because I am a non-smoker, and because I taught biology, I was very anti-smoking.
I had absolutely no symptoms at all apart from being tired, but I thought that was just because I was coming up to 60 and still working with teenagers.
The surgeon said to me at the time 'we never catch it at stage one, your dog has saved your life. Now go away and do what you want.'
I was just so lucky. Every day is special with her. To catch it at stage one is just remarkable. I don't know how I would have survived with radiotherapy and chemotherapy. She saved me a lot of fuss.
It was incredible that he found it so quickly, particularly as when he first started sniffing there wasn't even a lump yet.
He obviously realised I smelled different from normal.
It is something that, at the back of my mind, I thought 'I would actually quite like to do that'.