Changes in body fluid odors can be used to identify the presence of lung cancer tumors, has been shown in a new study by American researchers.
The research by scientists at the Monell Center and collaborators may help in methods to identify potential diagnostic biomarkers for lung cancer in human urine.
Monell biologist Gary K. Beauchamp, a senior author on the study, said: "Cancer tumors result in a change in body-related odours that can be detected both by trained animal sensors and by sophisticated chemical techniques.
"These findings indicate that odour sensing has the potential to improve early diagnostic and prognostic approaches to lung cancer treatment."
The scientists used a controlled animal model to reduce many confounding factors frequently found in human patient studies.
In behavioural studies, sensor mice were first trained to recognize the scent of urine of animals with lung cancer tumours. The trained sensor mice were then able to use urine odour to make a difference between tumour-bearing from healthy animals.
Chemical examination of urine compounds showed that the amounts of several chemical compounds differed significantly between tumour-bearing and healthy mice. Interestingly, the levels of many of these compounds were lessened in tumour-bearing mice rather than increased, which is often expected.
After experimenting more, the researchers were able to identify tumour-bearing from control mice simply by measuring the amounts of these biomarker chemicals in mouse urine and then creating chemical profiles. This chemical classification was accurate enough to identify 47 out of 50 mice as tumour-bearing or healthy.
The findings show that lung cancers produce changes in odorous compounds secreted in urine and that these changes can be detected and used as markers for the disease.
Steven M. Albelda, a senior author on the paper and William Maul Measey Professor of Medicine, University of Pennsylvania School of Medicine, said: "Finding new ways to screen for early lung cancers in patients at risk, such as smokers, is one of the best ways we have to reduce the high death rate from this disease,"
Albelda added: "Using the same chemical approaches as in this paper, we hope to be able to detect odors in urine of smokers that could be used to identify lung cancer at a very early stage."
The study has appeared online in the journal PLoS One.