It’s no secret that dogs, through the wonders of their noses, can identify several types of cancers, including prostrate, breast, colon, lung, thyroid and ovarian cancers, and melanoma. However, as fascinating as this ability is, it’s unlikely that dogs will be “working” side by side in-clinic with general practitioners and oncologists anytime soon.
So why, then, does it matter whether dogs can sniff cancer? What’s the practical application?
The future possibilities are significant, according to Cynthia Otto, DVM, Ph.D., executive director of the Penn Vet Working Dog Center, associate professor of critical care at University of Pennsylvania School of Veterinary Medicine and researcher into the impact of 9/11 on search-and- rescue dogs.
Dr. Otto and her group, working in collaboration with Monell Chemical Senses Center, Penn Physics and Penn Medicine, are close to identifying the specific chemicals dogs are targeting when they “smell” ovarian cancer, which could result in an early detection blood test, she said.
By the time ovarian cancer is diagnosed, aggressive treatment is required—often without success.
“If a simple blood test could offer a very early diagnosis, many lives would be saved,” said Vallie Szymanski, co-founder and executive director of Ovarian Cancer Symptom Awareness (OCSA), a St. Charles, Ill.-based nonprofit that helps fund Otto’s work. One OCSA fund is named for Darlene Arden, an award-winning pet author and certified animal behavior consultant who succumbed to ovarian cancer in February.
One of several project collaborators is an oncological surgeon who provides the blood samples. The dogs sniff the samples of patients with ovarian cancer and are “clicked” (with a dog training clicker), and promptly rewarded with praise and a treat. Eventually, a normal blood sample is added to the mix, but the dogs are rewarded only when identifying the cancer sample. Finally, a sample is added from a woman with an ovarian-related medical issue, such a cyst (benign ovarian disease). Dogs quickly learn to distinguish between this “false alarm” and true cancer.
The dogs take about two weeks to begin to catch on, and after a few months of training, they get it right at least 85 to 90 percent of the time, according to Otto.
“This is clearly statistically significant,” she said. “There are three choices for the dogs, and only one is right. It’s mind boggling as to how dogs can do this so often. I am amazed at the possibilities.”
How Does the Nose Know?
Otto has partnered with chemists and physicists who are attempting to determine exactly what chemical changes occur in ovarian cancer patients. The physicists essentially are attempting to recreate a canine nose to find out what dogs are catching when they detect cancer.
Otto is confident that as long as she and her team receive ample financial support, she’s three to five years away from developing a blood test that essentially will translate what dogs are telling researchers. Unfortunately, most ovarian cancer groups aren’t interested in funding her work because “They don’t get it,” she said.
Another OCSA co-founder, Susan Roman, was one of the driving forces behind the organization.
“[Susan’s] dog Bacchus was so persistently sniffing at her,” Szymanski said. “She saw her doctor based on her dog’s insistence. She just thought her dog was trying to tell her something.”
She was right.
“Susan had no symptoms, but the diagnosis was ovarian cancer,” Szymanski said.
Sadly, despite Susan’s dog’s actions—and reasonably early warning—it wasn’t early enough, but from her diagnosis, OCSA and its promise became reality.
Why this Industry?
“There are several reasons why we partnered with veterinary medicine from the very beginning,” said Szymanski, whose father was a veterinarian. “It’s a profession dominated by women, and, obviously, reaching women is our target. We’re also reaching out to veterinary students.”
“I know how much our clients share with us,” said Kurt Kleptisch, DVM, of St. Charles, Ill., who serves on the OCSA Board. “Veterinarians know that it’s not unusual for clients to share their own health concerns with us. I point out I am ‘not that kind of doctor.’ But based on the trust clients have in me, they share. By making veterinarians aware of ovarian cancer symptoms and encouraging clients to see their doctors, we’ve helped a lot of people.”
“We’ve always known that dogs can play a role,” said Szymanski. “That feeling was based on Bacchus’ actions. But we didn’t know how vital that role might be until we were introduced to Darlene Arden, and then Dr. Otto.”
Arden was a steadfast believer in One Health long before the term was popularized. Shortly before her death, she established the Darlene Arden Veterinary Outreach Program Fund with OCSA.
If indeed the funding comes through, and progress continues, a blood test for ovarian cancer will happen, Otto said, adding that once the recipe is set, it will be reasonably easy duplicate the effort for other types of cancers, as well.
When given that news shortly before her death, Arden said, “Thank dog!”
Steve Dale writes every other month for Veterinary Practice News. A certified animal behavior consultant, he speaks at animal welfare and veterinary conferences. His website is www.stevedale.tv. Columnists’ opinions do not necessarily reflect those of Veterinary Practice News.