A new breath shows promise as a quick, non-invasive way to detect the early signs of gastric and esophageal cancers. In analyzing the breath test results of more than 200 patients, British researchers determined that the method was able to detect cancer tumors with 90% accuracy.
Study results were published in the Annals of Surgery. A global team of researchers contributed to this effort, including scientists at Imperial College London, clinicians at Imperial College Healthcare National Health Service (NHS) Trust, and researchers from University College London, Keele University Medical School, and the J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic.
Accounting for 15% of cancer deaths worldwide, the National Cancer Institute’s Surveillance, Epidemiology, and End Results Program reports that esophageal and gastric (stomach) cancers make up 2.6% and 1.8% of all cancer deaths in the United States, respectively. In addition, they contribute to more than 16,000 new cases diagnosed each year in the United Kingdom, said George Hanna, PhD, FRCS, MErgS, the study’s lead author and director of the National Institute for Health Research (NIHR)-Diagnostic Evidence Cooperatives at Imperial College London, in a statement issued by the college.
Detecting these cancers is done through endoscopy, which is costly and invasive and usually diagnoses the cancer after it has metastasized to other parts of the body. Both cancers are difficult to detect in early stages because they don’t show obvious signs and the long-term survival rates are poor: 15% for gastric cancer and 13% for esophageal cancer.
“Our breath test could address these problems because it can help diagnose patients with early non-specific symptoms as well as reduce the number of invasive endoscopies carried out on patients, which often lead to negative results. Diagnosis at an early stage could give patients more treatment options and ultimately save more lives,” Hanna said.
The test involves breathing into a breathalyzer-type device that is connected to a bag. Researchers used ion flow tube mass spectrometer to analyze the compounds in the exhaled breath of 210 patients who either had benign tumors or were at risk for developing these cancers. The study took place from 2011 to 2013.
Specifically, the test looked for volatile chemical compounds in exhaled breath that produce an odor specific to patients with these cancers. For those test subjects with gastric and esophageal cancer, 12 VOCs: pentanoic acid, hexanoic acid, phenol, methyl phenol, ethyl phenol, butanal, pentanal, hexanal, heptanal, octanal, nonanal, and decanal were found in much higher rates than in the noncancer control groups.
“In addition to these VOCs, butyric acid was significantly higher in the esophageal adenocarcinoma group than in the noncancer controls,” the article on the study’s findings, indicated.
Researchers are hopeful that the study’s results could be used to develop a set of biomarkers for these cancers.
The University College London Hospitals NHS Foundation Trust, The Royal Marsden NHS Foundation Trust, and Guy’s and St Thomas’ NHS Foundation Trust plan to conduct a follow-up trial of 400 patients that will hopefully guide the development of a sensor device for detecting malignant tumors in patients, according to the statement issued by Imperial College London.