Novel predictive biomarkers for cancer have been identified in breath by researchers at Imperial College London (ICL), UK, using two-dimensional gas chromatography with time-of-flight mass spectrometry. The technique enabled them to detect compounds they had not previously seen in breath samples.

Oesophago-gastric cancer is currently detected at a late stage in the disease’s progression by invasive techniques such as endoscopy. Professor George Hanna, head of the Department of Surgery and Cancer at ICL, plans to improve survival rates by use of non-invasive breath tests during triage. Breath tests would be a quick way to identify patients at risk, who would then be selected for an endoscopy at an earlier stage.

“However, breath samples are more complex than we first thought,” said Hanna. Breath consists of over 1000 volatile organic compounds (VOCs), some of which are present in trace amounts. “We needed to profile samples in as much detail as possible to be sure we didn’t overlook any compounds of relevance.”

GC×GC–TOF MS enabled detection of important trace compounds

Initially, the team was using thermal desorption (TD) to prepare samples and gas chromatography–mass spectrometry (GC–MS) to analyse them. “We were happy with the sample security provided by our thermal desorber from Markes International, especially the option to re-collect portions of our samples, which is very useful during the discovery phase,” said Hanna. “But we needed a GC–MS system that could offer more sensitive, confident identification of the wide-ranging volatiles in breath.”

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