Dogs Can Smell Lung Cancer on Your Breath, Even If You've Just Had Lunch

By Veronique Greenwood | August 22, 2011 12:24 pm

Specially trained sniffer dogs can smell something on the breath of lung cancer patients.

Dogs will sniff anything and everything, and can even tell identical twins apart by scent. And tumors, you may be surprised to learn, have their own very faint smells. To figure out how to diagnose internal cancers that are frequently overlooked until too late from just a breath sample, scientists have been working with dogs to see if these smells can be reliably differentiated from, say, the smell of breakfast, that last cigarette, or emphysema.

In previous studies, dogs have already shown their scent savvy in detecting established cases of ovarian cancer, colon cancer, melanoma, breast cancer, and lung cancer. In the latest study, which investigated how well dogs could make a diagnosis in the presence of other scents on a patient’s breath, canine breathalyzers not only smelled lung cancer even when a patient had recently eaten or smoked a cigarette, they also, importantly, didn’t mistake other scents, like those of emphysema or tobacco smoke, for cancer. This confirms the idea that lung cancer has a very specific scent of its own, and will galvanize researchers in their quest to identify exactly what the dogs are picking up on.

One thing to note, though: For the purposes of training dogs to identify the disease’s signature, studies of this sort usually use patients’ whose cancer has already been diagnosed and is more advanced that one might like. Early stages of the disease might have different or less noticeable markers in the breath, and studies that work only with early stage cancer, or collect many breath samples over time and see who develops cancer and when dogs start to pick up on it, would be a welcome addition.

Once a good chemical signature for early-stage lung cancer is deduced, scientists can finally put into action the electronic “noses” they have been developing for years: these super-sensitive chips can alert doctors to the presence of certain chemicals in the air, whether they are from bombs, rotting food, or cancer.

[via ScienceDaily]

Image courtesy of European Lung Foundation

CATEGORIZED UNDER: Health & Medicine
  • VIP

    “Dogs Can Smell Lung Cancer on Your Breath, Even If You’ve Just Had Lunch”.
    Knowing and having lived with dogs most of my life, and having cancer in my lungs, unfortunately dogs have a major problem telling you.

  • Bear

    Will dogs or carnivors in general eat cancerous tissue? Is it harmful to the dog? If not then what is the evolutionary advantage of being able to sniff out cancer?

  • pinky

    i don’t think it happens to be evolutionary for the purpose of dogs eating out the cancer or some similar business the evolution was dogs having very hightened sense of smell, we’re just taking advantage of that. this is pretty neat but the issue isn’t finding it, its getting rid of it. Maybe they’ll research leprosy or worms next?

  • Sammy

    This is very interesting… LOVELY!

    But what kind of dog is in that picture?

  • Sammy

    Also, VIP, these are trained dogs. They’re trained to smell out the smell of the cancer and, like most rescue and bomb search dogs, each one has their own liking. They’ll hint or do some type of movement that will tell you if you have it or not. Much like body searching dogs and everything. Your dogs aren’t trained, therefore they don’t know what to say when they smell it, because they know nothing of it.

  • gary lynn

    And cats just still suck out
    your life’s breath, right?

  • Suzanne

    I’m wondering if I’ve been smelling my husband’s GI tract cancer on his breath. After several rounds of chemo, he’s starting to smell more like himself than he has in a long while. It’s weird and not something that would be obvious to anyone else. I only notice every now and then when I’m standing close enough to him. He did have a very large tumor and the doctors are pretty sure it’s shrinking with therapy. If that is what caused his change of smell, I wish I’d known the first time I smelled it.

  • Linda Caskey

    so how do u know thats what your dogs smelling or how do they react


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