The device is so sophisticated it can sniff out malignant head and neck cancer tumours that are often hard to diagnose.

It picks up on microscopic chemical changes that are emitted in the breath of people with the two cancers, compared to those without the disease.

The Nano Artificial Nose ? or Na-Nose ? has been tested on a small sample group but there are hopes it could one day be used as a routine test on the cancers, which affect 8,700 people a year.

Patients develop tumours of the head, neck, salivary glands and mucus membranes.

These cancers are hard to spot early and are often not diagnosed until the cancer has spread to other parts of the body, by which time it is in its advanced ? and sometimes incurable ? stage.

The Na-Nose was able to tell apart breath molecules from head and neck cancer patients and healthy people. it also distinguished between lung cancer patients and those free of the disease, and between head and neck cancer and lung cancer patients.

There?s an urgent need to develop new ways to detect head and neck cancer because diagnosis of the disease is complicated

Professor ?Hossam Haick

Israeli scientists ?collected breath samples from 82 patients who had head and neck cancer, lung cancer, or were cancer-free.

Professor ?Hossam Haick, from the Technion ? Israel Institute of Technology, said: ?There?s an urgent need to develop new ways to detect head and neck cancer because diagnosis of the disease is complicated, requiring specialist examinations.

?We?ve shown that a simple ?breath test? can spot the ?patterns of molecules which are found in head and neck patients in a small, early study.

?We now need to test these results in larger studies to find if this could lead to a potential screening method for the ?disease.?

The study is published in the Journal of Cancer Research, owned by Cancer Research UK.

Dr Lesley Walker, the charity?s head of cancer information, said: ?These interesting initial results show promise for the ?development of a breath test to detect head and neck cancers which are often diagnosed at an advanced stage.

?But it?s important to be clear that this is a small study, at a very early stage, so many more years of research with patients will be needed to see if a breath test could be used in the clinic.?

Head and neck cancers are more common in heavy drinkers and smokers.Poor diet and exposure to the sexually transmitted human papillomavirus (HPV) are also triggers.

Symptoms can include mouth ulcer that don?t heal for weeks, and difficulty swallowing.