Why Don't We Have Cancer-Sniffing Dogs?

There are a lot of stories out there about dogs who seemed to smell lung cancer on their owner’s breath, and a recent study found that some dogs can detect lung cancer in blood samples with astonishing accuracy. So why aren’t there domestic dogs trained to detect cancer in every hospital on the planet?

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[macnutz]

Six years ago, when I was feeling very ill, my all Canadian doggy (Heinz 57 breed) started stuffing her nose under into my right armpit, really pushing to get her nose in, only on the right side.
Then I was diagnosed with large B cell lymphoma, in stage four. Of course, the big tumor was in my right armpit. I should have listened to my daughter dog.
I survived and am out of danger after over five years of complete remission. This one very rarely returns at that point.

[VegQuaker]

I think one reason there are so many stories of dogs detecting their owner's cancers and tumors is because the dogs are familiar with the "normal" smell of the person and may smell a change.

I had a brain tumor that started to grow faster (still was a slow growing and benign one) and my dog would sniff my head and cry.

[Master_Therion]

Every hospital should have a cancer detection Lab... rador Retriever.

[allenmitchell]

I don't have cancer, but I have a dog that lets me know when my blood sugar gets low. He will come over and bump me with his nose until I check my blood. He has received no training for this.

[Linkrules]

There is a charity in the UK called Medical Detection Dogs that is working to achieve exactly this, although rather than having dogs in the hospital the hospital would send samples off to the site with the dogs. My dad worked with the charity for a while, and it's amazing what they can do. While dogs are fallible, the rate of false positives and negatives on current prostate cancer detection methods short of a biopsy (painful, invasive and extremely expensive) are way, way higher, and the science behind electronic noses is likely at least a couple of decades away from being as accurate as the dogs are right now.

[Beakerzor]

3:47 sniffing for bombs is also extraordinary unrewarding, which is why they let them find a planted toy/sample after a while, they can use the same trick for labs

[tedmattingly]

Im a disabled veteran and my service dog helps me with mobility issues from my bone marrow cancer. But we found out "accidentally" that she could actually give me a few minutes warning of me blacking out or passing out. We were able to work on that and she constantly gives me those warnings and keeps me from bouncing off the ground, all because she can smell something different. She gives me so much more freedom and lets me enjoy what part of life I have left.

She's a 1 year old German Shepherd and her name is Battle.

[Master_Therion]

I don't think he could sniff out cancer, but every time I let my dog out he gives the backyard a CAT Scan.

[bla]

Dogs ability to smell cancer makes sense.

I work in EMS, in a few years ago we got notified of a possible dog attack.
When we arrived on scene we found a great Dane holding down a child.

Come to find out it was not an animal attack.
The child had a severe seizure disorder. The dog was trained to smell the seizure before it began. Would warned the person that the seizure was about to begin. And then hold down the childhood that they would not hurt themselves until the seizure had passed.

[KimberlyGraceArcher]

Dog trainer here! As far as their reinforcement, there's actually a pretty simple solution - plant positives. Random reinforcement actually works great for dogs, it's like a slot machine! From what I can tell, money is actually the biggest barrier. It would take a long time to train the dog and a ton of labor to find and train those dogs. It's definitely doable, just probably not worth it.

[JustMeJH]

Fascinating insights on how far we’ve come in diagnosing cancer, and how awesome our furry friends are. Also, you had me at risqué :)

[genobreaker]

This was actually something I had wondered about. Thank you.

[WakarimasenKa]

Saw some engineer or something talking about how we were able to make detectors that were better than a dogs nose, but the trouble was that they didnt have the "brain" to interpret things the picked up and that is why we dont have a cancer sniffer gadget.

[unusefulidiot]

If a dog would detect cancer in me, i would be willing to tour a few other hospitals to give other dogs a true positive to test. That would give the trainers the possibility to reinforce a positive outcome for the dog in case of a positive detection.

[zeratulrus]

I know I'm not a dog, but that weird smell I've felt for the past 10 years every few months for a couple days is really getting to me, I need to get tested for cancer, to put my mind at ease if nothing else.

[isaachibben]

I can imagine if cats being able to, but just not giving a crap. Leave the owner to die unknowingly so that feline can claim dominance or just free range to lay on the keyboard

[AverytheCubanAmerican]

Even if they can't do that, they're still good bois that deserve bepis

[isstinna]

I think I am a dog. I too need a positive reifrcement after I do something great in my job right away and I get bored of doing the same task over and over.

[lisaseeman]

We can have known samples from cancer patients mixed in. When they find a known one they get the reward. They don't get a reward for every one one can work out a threshold

[purplealice]

We could start with samples we already know are cancerous or negative, and then reward the dogs when they choose the right ones. And we also have electronic sensors that can detect VOCs, so we need to work on determining which VOCs are associatedwith which conditions.