Search Menu
In Situ Foundation

We all know dogs possess incredible powers of smell. Some have even been trained to sniff out diseases like diabetes and cancer. But exactly how is this superpower put into practice by research centers and healthcare providers around the country? Cancer-detecting canines and their handlers across the country offer the lowdown on the latest life-saving adventures of man’s best friend.

How Do Dogs Detect Cancer?

Cancerous cells produce a very specific odor. In fact, in the late stages of the disease, even human noses can detect it. With a sense of smell that researchers estimate is between 10,000 and 100,000 times superior to ours, dogs can detect this smell far earlier in the disease’s progress—even while the cancer is still “in situ,” or has not spread from the site where it was first formed. Remarkably, they don’t even need to smell the growth directly. Dogs can detect this scent on waste matter like breath.

That makes the work of training a dog to detect cancer a lot simpler. Dina Zaphiris, founder of the nonprofit cancer-dog training organization In Situ Foundation, developed the first protocol for training cancer-detecting dogs. Having trained 52 dogs to detect cancer, she now trains dog handlers from around the world. The goal is to help to spread this life-saving knowledge to all who need it.

Each In Situ dog trains for up to eight months. During this time, they smell samples of breath, plasma, urine, and saliva collected by doctors and sent to the foundation. After smelling more than 300 unique samples, dogs are able to distinguish between a healthy sample and a cancerous one. They also learn to “generalize” the smell, meaning they can transfer what they know about the smell from previously-tested samples to new, similar samples.

Cancer-Detecting Dogs in Action

At In Situ, Dina Zaphiris has trained dogs to work with research teams at hospitals and universities, distinguishing healthy samples from cancerous samples for teams at Duke University and the University of California, Davis. Now, In Situ is preparing to roll out the first-ever hospital-backed program to use cancer-detecting canines among the public, providing early screening for firefighters in California, who are at high risk of developing cancer because of all the toxins they’re exposed to in fires, including California’s deadly wildfires.

Elsewhere, cancer-detecting dogs are being trained not to work directly on early screening for the public, but rather to help researchers gather data they will use to build a “mechanical nose”—a device that will detect odors just like a dog’s nose, without the need to train multiple dogs or account for the unpredictabilities of working with living beings. The Penn Vet Working Dog Center is working with a team of all-star dogs like Osa (below) to develop a mechanical nose as soon as possible.

For many cancers, there’s currently no screening method available: people don’t know they’re suffering from the disease until they start to experience symptoms. And no variety of cancer currently has a reliable screening method for the disease in its earliest stages. This means that someday in the not-too-distant future, dogs’ noses will be saving many thousands of lives, whether it’s through a mechanical nose or a real, live four-legged friend.

So, who are these wonder dogs, and what are their lives like?


Photo courtesy of In Situ Foundation

As Dina Zaphiris’s dog, 10-year-old Australian Shepherd Stewie has been sniffing cancer samples since she was 8 years old. She loves swimming and playing with Dina’s other dog, Splitty, a 1-year-old Border Collie. Like all the dogs Zaphiris trains at In Situ, Stewie works only in a laboratory setting. Three days a week, she goes to the lab to take turns sniffing samples with her cancer-detecting canine companions. But she never has to wait long for her turn . In fact, it only takes a dog 30 seconds to smell 10 samples. The work is so fun that it feels like play to Stewie and her stablemates. They always want to keep on sniffing after the day’s work is done.


Photo courtesy of In Situ Foundation

Another dog from In Situ’s program, Yellow Labrador Retriever Enloe is supported by the Enloe Medical Center and Enloe Regional Cancer Center in Chico, where In Situ is based. Enloe is something of a local celebrity, with people around Chico following his training. He’s extremely driven for food and toys, which makes him a great cancer-detection dog, as he’s always keen to get his reward. Enloe has a loving family in the community to go home to every night after a fun day’s work training.


Photo courtesy of Shelby Wise

Osa is a star of the cancer-detection program at the Penn Vet Working Dog Center. She entered the center as a puppy and tried all the careers available to her there. Osa ultimately found her niche on the cancer-detection team. She immediately loved the work and was always excited to go to a day’s training. These days, she lives with her handler in New Jersey and completes two or three cancer-detection sessions every week. The rest of the week, her trainer keeps her happy and busy with agility and obedience training, a fitness program, and live human searches. When she entered the program at Penn Vet, Osa was sometimes reactive toward people. But that’s all in the past now. Her work as a cancer-detecting canine has made Osa a happier, more confident, and more trusting dog.

Related article: Five Inspiring Dogs Honored With 2023 AKC Award for Canine Excellence
Get Your Free AKC eBook

Does Your Dog Have What it Takes to be a Therapy Dog?

My dog is great with people, I want her to be a therapy dog. Where do I start? If you have asked this question then this e-book is for you. Download to learn more about Animal Assisted Therapy and how to get started.
*Turn off pop-up blocker to download
*Turn off pop-up blocker to download