Checkup: Cancer Sniffing Dogs
One of the toughest things about treating cancer is that itís really hard to detect early on. And so scientists are looking for better ways to catch the disease in its earliest stages. One promising line of research involves dogs that can literally smell cancer.
"When I initially heard about this I was quite honestly a bit skeptical."
Thatís Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society.
"Well, letís just say that after having seen the results of a number of experiments, I do believe that there is something there."
For example, researchers in Germany trained dogs to detect lung cancer by sniffing patientsí breath samples. The dogs performed better than standard imaging tests, correctly identifying cancer in 71 out of 100 samples.
So what, exactly, are the dogs smelling?
"What theyíre smelling is obviously a complex mixture of organic compounds or what we would call volatile compounds -- that is, elements that are being put off by cancers that are able to transfer from a liquid into a gas form and then the patient exhales that gas and the dogs are able to smell it."
But because dogs canít describe what theyíre smelling, researchers are still in the dark as to what, exactly, constitutes the chemical signature of a given cancer. So unless scientists can teach dogs to talk, which seems unlikely, they still have a long way to go to make use of these dog sniffing experiments.
"First we have to be able to identify what the dogs are smelling, then we have to be able to tease apart the various signatures of the compounds that are in breath samples and then translate that into some sort of machine approach."
And then, Lichtenfeld says, you have to take all that into the clinic and see if knowing what cancer smells like can help detect it early. That may or may not pan out, but if it does, weíll have dogs and their high-powered noses to thank for pointing us in the right direction.
Iím Jeremy Shere.