A dog detected cancer in her husband by smell. Years later, he also saved his wife

Most people notice when their dog behaves strangely. Few would imagine that this behavior could be a sign of cancer.

Will the cancer has a smell?

Scientists have been exploring this hypothesis for the past two decades, but to Chase Johnsona 36-year-old lawyer from North Carolina, in 2021 the idea became real in an unexpected way.

Your dog, usually calm and relaxed, began to appear restless and to repeatedly fixate on a specific point on your body.

This unusual behavior ended up leading her to discover a lump in the breast — later identified by doctors as triple negative breast cancera fast-growing and very aggressive form of the disease.

“O Salvation he is a very calm dog; never get anxious and it’s always very calm. One day he became extremely agitated and placed his nose against my chest. He did it a second time, and it hurt; That’s when I started feeling around and found the nodule. If he hadn’t done that, I wouldn’t have found him,” Johnson told .

The idea of ​​a dog being able to smell cancer may seem bizarre, but several studies have shown that trained dogs can sometimes detect the disease in breath samples, or just by smell.

For example, one from 2006 published in the magazine Integrative Cancer Therapies concluded that trained dogs could identify cancer samples of the breast with a sensitivity of 88% and specificity of 98%.

Researchers are now trying to identify the specific molecules that these dogs can detect, with the aim of developing standardized “electronic noses” that could become a non-invasive tool for early diagnosis.

A dog’s nose led to a life-saving exam

Chase Johnson lives in Cary, North Carolina with her husband, Ben Byrnand the dog Ceto, a Labrador retriever cross. Keto had always been a companion calm, rarely showing signs of anxiety. But, in January 2021, his behavior changed.

The dog started walking from side to side through the house and then closely followed Johnson wherever she went. Whined more than usual and seemed restless for no apparent reason. Initially, the couple limited themselves to questioning what could have upset him.

Then, one day, Ceto pressed his nose firmly against the breast Johnson’s left. When he did it again, the pressure caused discomfort. Intrigued by the area the dog insisted on drawing attention to, Johnson examined herself and noticed a small nodule with a springy texture.

He tried to make an appointment with his attending physician, but was told that the first available space only existed in May 2021.

“I told them I had found a lumpbut they told me that I was too young to have cancer. They said that cancer doesn’t hurt, so it was probably a benign cyst, nothing to worry about, and that it would return in May,” said Johnson.

The explanation made her uncomfortable. Part of his concern came from a previous experience: Keto had already behaved similarly and anxious with her husband, before he was diagnosed with colon cancer.

Because of this background, the couple suspected that the animal’s behavior could beonce again serving as a warning. To get a clear answer, Johnson contacted a doctor at Duke University Hospital and explained the situation. It ended up being referred for additional examinations.

Doctors performed a mammogram, an ultrasound and a biopsy. On February 16th, the results confirmed triple negative breast cancer.

O treatment started quickly. Johnson underwent chemotherapy, radiation therapy and surgery to remove the tumor, as well as the removal of lymph nodes. The treatments were successful and currently shows no signs of the disease.

“After the diagnosis, I met with my oncologist and she told me at the time that, If I had waited until Maywe would be having a very different conversation and I might not have survived,” Johnson stated.

What science says about dogs that detect cancer

Johnson’s experiment may seem extraordinary, but scientific studies suggest there may be a biological explanation. Cancer cells produce characteristic chemical substances known as volatile organic compounds (COV).

These substances can circulate throughout the body and appear in body fluids or on the breath, creating odor patterns that particularly sensitive noses can detect, explains .

Dogs are especially well prepared for this task. Their nose contains hundreds of millions of olfactory receptors, which allow them to detect odors in concentrations much lower than those perceptible to humans.

Still, scientists emphasize that the phenomenon remains far from being fully understood. Different studies use different training methods, sample types and testing conditions, which makes comparison difficult between results.

Scientists also still don’t know exactly what the molecules are that dogs can detect and, because of these uncertainties, animals cannot, for now, be used as a standardized medical screening tool.

Cases like Johnson’s highlight the importance of subtle biological signals in the early detection of diseases. If scientists can identify the “chemical fingerprints” that dogs can apparently pick up, it may become possible to design electronic sensors or respiratory tests capable of detecting cancer at very early stages.

While scientists continue to investigate whether dogs really have the ability to smell cancer, as everything seems to indicate, Case Johnson’s experiment shows the extent to which the early detection can be decisive.