A breathalyser could pick up on head and neck cancer, research suggests.
The disease makes up 6% of all cancers worldwide, killing more than 300,000 people a year.
Treatment is most effective during the early stage of tumour growth, however, vague symptoms mean the disease is often spotted when advanced.
To help pick up on earlier cases, scientists from Flinders University in Adelaide developed a device that detects volatile organic compounds – gases produced by the metabolism of cancer cells or the immune system – in the breath.
When tested on 181 suspected head and neck cancer patients, who were later diagnosed via a tissue analysis, the breathalyser accurately detected cases up to 86% of the time.
Head and neck cancer is a general term for more than 30 types of tumours, like those affecting the larynx, tonsils or tongue.
Symptoms can be vague and non-specific, for example mouth cancer often results in persistent ulcers, while laryngeal tumours may make the voice sound hoarse.
Head and neck cancer has been linked to smoking, excessive alcohol consumption and poor oral hygiene.
Diagnoses are said to be on the rise among younger age groups due to the human papillomavirus (HPV), a sexually transmitted infection that can spread through oral sex.
“We sought to determine the diagnostic accuracy of breath analysis as a non-invasive test for detecting head and neck cancer, which in time may result in a simple method to improve treatment outcomes and patient morbidity,” said the scientists.
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After using the breathalyser, tissue analysis revealed two thirds (66%) of the 181 suspected patients had early-stage primary tumours – cancerous masses that have not spread beyond their original site.
A further 58% had regional node metastasis, defined as cancer entering the lymph nodes.
Results – published in the British Journal of Cancer – reveal the breathalyser had a sensitivity of 80%, which describes a device’s ability to correctly identify those with a disease.
Its specificity (ability to spot those without a condition) came in at 86%.
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“Breath analysis for non-invasive diagnosis of HNSCC [head and neck squamous cell carcinoma] appears to be practical and accurate,” wrote the scientists.
“Future studies should be conducted in a primary care setting to determine the applicability of breath analysis for early identification of HNSCC.”
Co-lead author Dr Nuwan Dharmawardana added: “With these strong results, we hope to trial the method in primary care settings, such as GP clinics, to further develop its use in early-stage screening for HNSCC in the community.”
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