The news: Man's best friend could be cancer's worst enemy. A study by University of Pennsylvania researchers found that a trained dog could sniff the scent of ovarian cancer in tissue samples over 90% of the time, potentially generating a reliable new early-detection test for a disease that causes over 14,000 deaths a year.
Also recently, Italian researchers claimed that a dog was able to sniff out organic compounds related to prostate cancer (which kills 29,000 U.S. men every year) with over 98% accuracy. From NBC News:
Gianluigi Taverna of Humanitas Research Hospital in Milan and colleagues took urine samples from 320 men with prostate cancer, and 357 without it. The men with cancer had all different stages of the disease, from very low-risk, slow-growing tumors, to cancer that had spread.
Some of the men in the non-prostate-cancer group had other diseases or conditions, including other types of cancer.
One of the dogs detected every single prostate cancer case, and only hit false positives — when it identified cancer when it wasn’t there — in 2 percent of cases. The other dog was almost as accurate.
Taken together, the two dogs had an accuracy rate of 98 percent, the team reported to the annual meeting of the American Urological Association Sunday.
"We have definitely turned what used to seem a myth into a real clinical opportunity," said the Italian team in their study's abstract.
How effective is it? While a rate of 98% might seem pretty good, criticisms of the Italian study include that the dogs could have been sniffing out cancer-treatment drugs rather than the disease instead, which could make the study worthless — and that reliable tests with a higher accuracy and lower false-positive rate for prostate cancer already exist.
No one is suggesting relying on canines alone. But dog trainer Dina Zaphiris, who is applying to the FDA to create a canine medical scent detection kit which could potentially act as an "early warning test" for cancer patients. The results would be used in conjunction with other non-invasive tests (like a mammogram) before proceeding to a more invasive procedure like a biopsy.
Experts question the viability of canine-based systems, saying it has not been established which breeds of dogs are best, how they can be used systematically, or whether the resulting system would be financially viable. Additionally, a machine or chemical test which could isolate cancer-related particles from a sample could cost less and be easier to improve and administer.
In other bizarre news, earlier this year a Doberman pinscher was credited by his Staten Island owner of correctly identifying and alerting her to a malignant breast tumor.
Will dogs be sniffing me for cancer soon? It seems rather unlikely. But people are already trying to get dogs to sniff their tissue samples.
According to Zaphiris, "You should see the amount of e-mails I get saying 'I got an unclear mammogram and I don't know if I want a biopsy so could I have dogs screen my breath sample?'"