An odor based test that detects vapors from human blood plasma samples was able to tell the difference between benign and cancerous cells with up to 95% accuracy, according to work presented this week at the American Society of Clinical Oncology meeting in Philadelphia.
The study was led by scientists at the University of Pennsylvania and Penn Perelman School of Medicine and utilizes artificial intelligence (AI) and machine learning to analyze molecules called ‘volatile organic compounds,’ (VOCs). These are released from cells in blood and tissues and the ‘electronic nose’ contains nanosensors which are calibrated to detect VOCs.
The researchers took samples from 20 patients with ovarian cancer, 20 with non-cancerous ovarian tumors and 20 people who had no tumors at all and found that the electronic nose could tell apart the ovarian cancer samples with a 95% accuracy. The tool was 90% accurate in a similar experiment on pancreatic cancer samples and control samples. Another recent experiment on a small number of prostate cancer samples gave similar results.
“It’s an early study but the results are very promising,” said A. T. Charlie Johnson, PhD, the Rebecca W. Bushnell Professor of Physics and Astronomy in Penn’s School of Arts & Sciences and lead author of the presentation. The tool was also able to successfully detect patients who had early-stage cancers, which can be an issue for some types of detection systems.
“The data shows we can identify these tumors at both advanced and the earliest stages, which is exciting,” added Johnson.
The technology for the identification of VOC patterns is similar to how the human olfactory system works where the brain is able to identify complex mixtures of compounds and distinguish them as different smells. Similarly, dogs with their exceptionally sensitive noses can be trained to detect explosives, drugs and specific foodstuffs and some studies claim that they can also be trained to pick up particular patterns of VOCs to detect human disease.
Future work will analyze just how early the tool might be able to identify cancers, as well as whether the tool can distinguish between localized tumors and cancer which has spread to other sites in the body. The team have also collaborated with VOC Health, a company which specializes in diagnosing disease by detecting VOCs.
“If developed appropriately for the clinical setting, this could potentially be a test that’s done on a standard blood draw that may be part of your annual physical,” said Johnson.