Just a Breath Away: A New Way to Detect Cancer
Written by Rachel Larson
Edited by Aaron Wright
Jan 18, 2021
Edited by Aaron Wright
Jan 18, 2021
One of the most important predictors in cancer survival is early detection. Patients whose cancer was detected early often experience vastly better outlooks and easier recoveries than their counterparts, and so one major focus of cancer researchers is to find easy-to-use and non-invasive ways to detect cancer. For example, mucosal head and neck squamous cell carcinoma (HNSCC) is a type of cancer that appears as lumps in the mouth and neck of patients. Detection of this cancer requires a doctor to stick a camera down the patient's esophagus, as well as a biopsy of any suspicious lumps, which is both extensive and uncomfortable. However, researchers in Australia recently published a finding in the British Journal of Science that proposes an exciting and far less invasive method to catching HNSCC: using a breathalyzer.
Some molecules that our bodies naturally produce easily evaporate and so are called volatile organic compounds (VOC). Different VOCs are made by different types of cells, and HNSCC cells are associated with a few unique types of VOCs. In this experiment the researchers programmed a machine to be able to detect three common types of VOCs associated with HNSCC in the breath of patients.
How is a machine able to tell the difference between a normal VOC versus a cancerous VOC? Well, throw a golf ball in the air and catch it, then throw a basketball in the air and catch it. Did you do it? I didn’t think so, but your intuition about what would happen is correct: it would take far more energy for you to stop the basketball compared to the golf ball. The same thing happens to molecules. Heavy molecules, when shot out of a high speed accelerator, will not stop moving unless a relatively large force is applied, while small molecules will stop when a relatively small force is applied. Separating molecules using this technique is called mass spectrometry, and scientists can use this method to study what types of molecules appear in a sample, and determine which of those molecules are VOCs associated with HNSCC and which are not.
The accuracy of this machine was tested on patients in the Flinders Medical Centre and the Royal Adelaide Hospital in Australia. Patients confirmed to have HNSCC breathed out into a bag for fifteen seconds, after which the researchers analyzed the molecules in the breath with the mass spectrometry machine, and found that it was able to make an accurate diagnosis of HNSCC eighty percent of the time. Though more research must be done, this is an exciting discovery. More sensitive detection and controls for variables like smoking, what patients ate that day, and the stage of the HNSCC must be accounted for before this discovery can be implemented on a greater scale. However, the future looks bright for this novel form of cancer detection.
Works Cited
Dharmawardana, Nuwan, et al. “Development of a Non-Invasive Exhaled Breath Test for the Diagnosis of Head and Neck Cancer.” Nature News, Nature Publishing Group, 9 Sept. 2020, www.nature.com/articles/s41416-020-01051-9.