An oncologist who smells cancer? It’s not impossible
Key Takeaways
Industry Buzz
"As a coroner of the biggest county in my state, I can confirm this. I can smell a cancer patient, and my ex-wife was an oncologist and she could smell as well." — @Legitimate_Metal887
It sounds like the plot of a medical drama: A healthcare workers claims they can smell when someone has cancer.
But a (now deleted) viral Reddit post ignited interest in that exact phenomenon, with a user alleging they’ve always been able to smell when people have cancer.
"As a coroner of the biggest county in my state, I can confirm this. I can smell a cancer patient, and my ex-wife was an oncologist as she could smell as well. [It] smells like an old closet that hasn't been open in years mixed with weed killer smell. It is very hard to describe. Handled 25k plus bodies, and I am right about 85% without even opening the chart. Sometimes, they were undiagnosed until an autopsy was done," he wrote.
Outlandish? Maybe. But science suggests there may be something to it.
Comments pour in
Before diving into the science (which does exist)—you might find the anecdotal evidence in support of this claim shocking. People—both in and out of the medical field—have added comments about their own experience with this phenomenon. Here are just a few:
"For me, both as a layperson and having worked in oncology, I can smell when someone has a GI cancer. I believe it’s because I can smell the partially digested blood on their breath. There have been a handful of times I smelled it before they’d received a diagnosis, and unfortunately it’s been devastating and correct every time. It’s quite distinct. There are a few odors like that in the medical field." — @_Oops_I_Did_It_Again
"My first job as a nurse was in oncology. After smelling it enough, you recognize it. Lung cancer patients are the most obvious for me." — @theroguesstash
The nose knows—sometimes
Human noses might not be as useless as we think. Some studies have shown that dogs can detect cancer—particularly lung, breast, and prostate cancers—using scent alone. []
These highly trained dogs identify volatile organic compounds (VOCs) emitted by tumors and released through breath, sweat, saliva, urine, blood, or fecal matter. The theory is that cancers alter cellular metabolism, which changes the VOC profile of bodily fluids and emissions. []
Past research has demonstrated that dogs can detect viable cancer cells or molecular cancer markers with high sensitivity (97%) and specificity (99%) in ovarian cancer patients’ plasma samples.[] Other studies have shown similar detection rates for breath samples from lung cancer patients. []
The science of cancer’s scent
In controlled lab settings, scientists have identified specific VOCs emitted by cancer cells. For instance, lung cancer cells produce alkanes and benzene derivatives that can be exhaled.[] Ongoing research aims to build “electronic noses” that mimic this olfactory detection using sensors and machine learning. [] Some devices are already in early clinical testing for lung, ovarian, and prostate cancer screening.[]
As far as smelling cancer outside of the lab—a few individuals have made headlines for it.
Most famously, a Scottish woman named Joy Milne noticed a musky scent on her husband years before his Parkinson’s diagnosis. [] She later correctly identified Parkinson’s patients in a blind smell test and has since worked with researchers studying VOCs linked to the disease.
Her case led scientists at the University of Manchester to identify specific chemical markers of Parkinson’s in sebum.
While this doesn’t prove humans can detect cancer specifically, it suggests that some people may be unusually sensitive to disease-related VOCs.
The bottom line
While there's no peer-reviewed evidence supporting the idea that an untrained person can smell cancer on others, the biological mechanism—cancer-altered VOCs—is real.
Whether any humans can detect it unaided is unclear, but it’s not entirely pseudoscientific. So the Reddit user’s claim? Probably unverifiable—but not biologically impossible.
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