A quick and simple breath test can diagnose stomach cancer, study findings reveal.
Scientists from Israel and China found the test was 90% accurate at detecting and distinguishing cancers from other stomach complaints in 130 patients.
The British Journal of Cancer says the test could revolutionise and speed up the way this cancer is diagnosed.
About 7,000 UK people develop stomach cancer each year and most have an advanced stage of the disease.
Two-fifths of patients survive for at least a year, but only a fifth are still alive after five years, despite treatment.
Currently doctors diagnose stomach cancer by taking a biopsy of the stomach lining using a probe and a flexible camera passed via mouth and down the gullet.
The new test looks for chemical profiles in exhaled breath that are unique to patients with stomach cancer.
Volatile organic compounds
Cancer appears to give off a signature smell of volatile organic compounds that can be detected using the right technical medical kit - and perhaps even dogs.
The science behind the test itself is not new - many researchers have been working on the possibility of breath tests for a number of cancers, including lung.
But the work by Prof Hossam Haick, of the Technion-Israel Institute of Technology, suggests it is a good way to spot stomach cancer.
In the study, 37 of the patients had stomach cancer, 32 had stomach ulcers and 61 had other stomach complaints.
As well as accurately distinguishing between these conditions 90% of the time, the breath test could tell the difference between early and late-stage stomach cancers.
The team are now running a bigger study in more patients to validate their test.
Kate Law, director of clinical research at Cancer Research UK, said: "The results of this latest study are promising - although large scale trials will now be needed to confirm these findings.
"Only one in five people are able to have surgery as part of their treatment as most stomach cancers are diagnosed at stages that are too advanced for surgery. Any test that could help diagnose stomach cancers earlier would make a difference to patients' long-term survival."