Dog detects bowel cancer
January 31st, 2011
06:30 PM ET

Dog detects bowel cancer

A dog in Japan is able to detect bowel cancer using its sense of smell, according to new research.

"We used the excellent ability of dogs to distinguish between different scents to examine whether odor materials can be used in the diagnosis of colorectal cancer," writes Dr. Hideto Sonodo in his study published this week in the medical journal Gut.

In other studies, dogs have been able to distinguish the smell of bladder cancer, lung cancer, and breast cancer.

In the new study, researchers collected breath and stool samples from patients with colorectal cancer. They placed one cancer sample and four non-cancer samples into light blue wooden storage containers, and in a series of "sniff" tests, commanded a black Labrador retriever to "Search!" for the container that held the cancer sample.

The dog sniffed out the cancer sample in 33 out of 36 breath tests and in 37 out of 38 stool tests. That's almost as accurate as a colonoscopy test for colorectal cancer.

In some cases the samples had come from patients with early stages of bowel cancer, suggesting the chemical compounds that give colorectal cancer its smell may be present early in the course of the disease.

Doctors currently use a fecal occult blood test to screen for cancer at early stages, but the study authors note the test is accurate in only one in 10 cases. An inexpensive, more accurate test to detect bowel cancer early could help in the fight against the disease, but don't expect dogs to take the place of colorectal cancer tests.

"It may be difficult to introduce canine scent judgment into clinical practice owing to the expense and time required for the dog trainer and for dog education," notes  Sonodo.

Instead, if the specific chemicals that produce the smell of colorectal cancer are identified, Sonodo says, a sensor could one day be substituted for the dog.

The dog learned how to search for the disease at the St. Sugar Cancer Sniffing Dog Training Center in Chiba, Japan.

soundoff (29 Responses)
  1. Veritas

    Dogs are very important to peoples survival and quality of life. Thier companionship is a priceless gift. It has been proven that having a dog around can lower blood pressure and give some people the strength to face another day. All i know is my dogs are friends that don't judge, love me unconditionally and would lay down thier lives in my defense.

    February 1, 2011 at 06:16 | Report abuse | Reply
  2. A. Nony

    Dogs treat people much, much better than people on average treat dogs. Millions of unwanted dogs are killed each year in the US; many others are abused. Spay or neuter your dog. Adopt a dog from a shelter or a rescue group. If you must have a "purebred" dog, adopt one from a breed rescue group. Report (and/or intervene) in abuse cases that come to your attention. Support legislation that makes cruelty to animals a felony with significant penalties. If you have dogs, think about whether you can give one more dog a home (maybe you can, and maybe you can't). And, stop saying that Michael Vick has paid his debt to society. He may have paid his debt in the sense that he served the term lax laws imposed, but he will NEVER be able to pay his debt to the animals he tortured and killed.

    February 1, 2011 at 09:22 | Report abuse | Reply
    • L.Hill

      I couldn't agree more. The laws in Georgia were/are not enough in cases of animal cruelty. Vick was personally involved in the torture and killing of so many dogs. How is 18 months enough punishment? Those dogs lived and died in the most hellish way. 18 months was not justice served!

      February 2, 2011 at 07:24 | Report abuse |
  3. alpg49

    I think Andy Rooney said it best: "An average dog is better than a great person." Adopt a homeless pet. See for yourself.

    February 1, 2011 at 09:49 | Report abuse | Reply
    • Oodoodanoo

      Nice quote. On the other hand, my son is like a little puppy, so I'm hoping for something great from him.

      February 1, 2011 at 13:52 | Report abuse |
  4. ApeHanger

    I feel sorry for the Lab having to sniff people's pooop. What a yucky thing to have to do.

    Along the lines of Andy Rooney's comment, the one I always liked was that of Mark Twain: "If you pick up a starving dog and make him prosperous, he will not bite you. This is the principal difference between a dog and a man."

    February 1, 2011 at 11:16 | Report abuse | Reply
    • Mary

      Sorry? This is a dog's favorite thing to do.

      February 1, 2011 at 11:33 | Report abuse |
    • CMH

      Have to agree with Mary here. One of a dog's favorite activities is to smell poop! (I love dogs by the way) Why do you think they greet each other by smelling each other's hind ends 🙂

      February 1, 2011 at 12:41 | Report abuse |
    • evoc

      Dogs roll in poop...they are drawn to it.

      February 1, 2011 at 12:44 | Report abuse |
  5. Jim

    This is just one more thing that makes dogs so awesome. Cat's, on the other hand, are pretty much useless. God bless!

    February 1, 2011 at 11:21 | Report abuse | Reply
    • Mary

      I use to think cats were pretty much useless, also, till they got rid of the mice; let's not forget that mice carry disease.

      February 1, 2011 at 11:26 | Report abuse |
    • Donna

      Guess you have never lived in a building with a mouse problem, Jim.

      February 1, 2011 at 13:15 | Report abuse |
    • T. Charles

      As a cat owner, I have never been plagued with roaches in my apartment, even though my neighbors have them all the time. Gross, yes, but cats love them and take care of the problem while you sleep.

      February 1, 2011 at 15:00 | Report abuse |
  6. Mary

    Sonodo says it may be too costly to use dogs for detecting cancer. Seriously? Don't you think this may be such an important diagnosis that people would be willing to start raising and training dogs just for this purpose?

    February 1, 2011 at 11:23 | Report abuse | Reply
    • Donna

      It would be interesting to know how long it took them to train the dog to do this. They routinely have dogs sniffing for bombs and drugs and things, right?

      February 1, 2011 at 13:16 | Report abuse |
  7. BillyD1953

    Sniffing out bowel cancer isn't such a big leap for dogs, since one of their favorite activities is sniffing out people's bowels.

    February 1, 2011 at 11:25 | Report abuse | Reply
    • Mary

      No one said it was a big leap for dogs. The big leap would be for doctors to take advantage of the non- invasive method of detecting cancer. Expect those who have a corner on the multi-billion $ industry to pooh- pooh this idea away. (really, no pun intended)

      February 1, 2011 at 11:30 | Report abuse |
  8. hannah1

    As a breeder/owner of German shepherd dogs (including 2 registered therapy dogs), I can say that canines are the most wonderful species on earth! (As opposed to cats, which are filthy, nasty, flea-bitten creatures that poop in peoples houses! UGH)

    February 1, 2011 at 12:02 | Report abuse | Reply
    • Donna

      AND this comment has nothing to do with the specific article at hand. Dogs poop where they aren't supposed to as well, like, on the couch. I have witnessed it first-hand.

      February 1, 2011 at 13:19 | Report abuse |
    • T. Charles

      Poop in people's houses? Better than pooping on the sidewalk where we all can see it, smell it, and track it into our homes.

      February 1, 2011 at 15:01 | Report abuse |
  9. Donna

    Random notes on the actual article itself-the dog in the pic is really a puppy. Seems like a file photo-would have been nice to see the ACTUAL dog. Also, I never knew there was a "Saint Sugar".

    February 1, 2011 at 13:23 | Report abuse | Reply
  10. JoAnn

    I should have been dead from colon cancer at the age of 42. A colonoscopy saved my life. Talk to your doctor, know your risk level and get screened. Love yourself.

    February 1, 2011 at 16:51 | Report abuse | Reply
  11. Craig Stevens

    Cats are anything but worthless.

    Mine gives me a cat scan all the time...

    February 2, 2011 at 12:27 | Report abuse | Reply
  12. Phil G.

    I have seen other dogs on television that could also detect other forms of cancer.

    It's an astounding technique that we need to develope and thank our four footed friends for being blessed with.

    Lets' save some lives here people.

    February 7, 2011 at 23:27 | Report abuse | Reply
  13. Lorelei

    My boxer/lab who was 9 years at the time found my breast cancer. For months he would nudge my breast with his snout. He did this every day. Months later I had a baseline mammogram, then biopsy which showed cancer. I didn't make the connection until after my mastectomy because as soon as I came home from the hospital my dog stopped the nudging & never did it again.

    February 26, 2011 at 17:36 | Report abuse | Reply
  14. Canines

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    April 14, 2012 at 00:22 | Report abuse | Reply
  15. Excellent Cancer Treatment

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    May 12, 2012 at 07:47 | Report abuse | Reply
  16. Ginger

    I’ve had digestive issues for 2 weeks now. My lab test have not come back. My dog lays on me and stares at me now I’ve been sick. Does he know more than I about my condition?

    May 8, 2020 at 20:14 | Report abuse | Reply

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