Scientists seeking a quick and affordable way to detect thyroid cancer have trained a dog to smell it on people, with really good results. In a US study, a German shepherd mix named Frankie detected thyroid cancer (or lack thereof) in urine samples with nearly 90% accuracy, Medical News Today reports. Trained to lie down if he smelled cancer and turn away if he didn't, Frankie got it right 30 out of 34 times in patients who'd already undergone biopsies and diagnostic surgery for abnormal thyroid nodules. The study's top investigator, Donald Bodenner, tells Discovery that Frankie was nearly as accurate as thyroid biopsies done with a needle. He's also cheaper and less annoying. "We would like to know what Frankie is smelling, [but] nobody knows," Bodenner tells the BBC.
His research team now plans to work with veterinarians in training two other dogs who already sniff bombs to detect thyroid cancer. Researchers also want to figure out what the dogs are smelling and possibly design "electronic noses" to do the job. All this would help people avoid invasive diagnostic procedures that "often yield uncertain results," Bodenner says, which lead to "a large number of thyroid surgeries performed unnecessarily." Meanwhile, thyroid cancer is spiking worldwide as the death rate remains stable, meaning doctors may be spotting thyroid growths that don't need treatment, the Guardian reports. Bodenner's dog-sniffing approach has worked before—with ovarian and prostate cancer—because, as PBS notes, a dog's sense of smell is up to 100,000 times better than ours. (But like other animals, their short-term memory stinks.)