[author: Gloria Malpass, Ph.D.]
Photo by National Cancer Institute on Unsplash
Clinical manifestations of head and neck cancers often occur only after the disease has reached an advanced stage. Development of new technology for earlier diagnosis is of critical importance. Since the nasopharynx, base of tongue, and larynx require examination by specialists using flexible endoscopes, a non-invasive test that could detect head and neck cancer and be administered by general practitioners would increase the likelihood that a patient would be referred to a specialist at an earlier stage.
Researchers at Flinders University in Australia have developed a novel, non-invasive breath test that has the potential to diagnose head and neck cancers. When humans breathe, they exhale organic molecules called volatile organic compounds (VOCs) from various body fluids. These potential biomarkers for cancer detection can be measured using mass spectrometers, instruments used to measure the mass to charge ratio of charged atoms or molecules, and gas detectors, devices that can profile complex gas samples by using computerized pattern recognition to distinguish between samples from cancer patients and those from healthy patients. In a study that included 50 control and 50 head and neck squamous cell carcinoma (HNSCC) patients, the Flinders researchers analyzed breath for VOCs and used statistical modeling to develop a breath test that was shown to differentiate cancer and control (benign disease) patients with a sensitivity, or ability to correctly identify patients who have HNSCC, of 80% and specificity, or ability to correctly identify people who do not have HNSCC, of 86% in the optimal model.
The Flinders researchers indicate that “[t]he predictive ability of this test is significantly higher than that reported for clinical symptoms and examination alone, suggesting that raw mass spectra breath analysis for HNSCC has the potential to improve current clinical practice.” (Dharmawardana et al., 2020) While the breath test would not replace clinical expertise and current diagnostic procedures, the researchers suggest that a positive test result could prompt an urgent specialist referral for further diagnosis. A negative test result could support the decision to observe the patient for a short period of time or to administer medical treatment and investigate further if symptoms persist.
· https://www.sciencedaily.com/releases/2020/10/201005101544.htm (News article)
· Dharmawardana N, Goddard T, Woods C, Watson DI, Ooi EH, Yazbeck R. Development of a non-invasive exhaled breath test for the diagnosis of head and neck cancer. Br J Cancer. 2020 Sep 9. doi: 10.1038/s41416–020–01051–9. Epub ahead of print. PMID: 32901136.