/ 23 June 2003

An electronic nose to sniff out cancer

Scientists have developed an ”electronic nose” that can detect lung cancer simply by sniffing a person’s breath, researchers say. The creators of the e-nose at the University of Rome hope it will one day be used as a new method of diagnosing the disease.

Like a real nose, the electronic version uses an array of sensors that are not designed to detect any one chemical. Instead, they respond to the overall profile of compounds in a sample. Such sensors are already used in the food industry to spot subtle ”off” smells and tastes.

The cancer-detecting Roman nose is able to spot the cocktail of chemicals — alkanes and benzene derivatives — exhaled by people with lung cancer. A variety of conditions can lead to specific compounds turning up in the breath. Other examples are aliphatic acids in the breath of people with liver cirrhosis, and di or

trimethylamine in the breath of those with failing kidneys.

The scientists tested their e-nose on 60 people at the Forianini Hospital in Rome, including 35 waiting for an operation to remove a large lung tumour. Each test took just over a minute and the nose successfully pinpointed every cancer patient, New Scientist magazine reported.

The next step will be to boost the nose’s sensitivity to the point where it can detect tumours at an early stage. Doctors currently use an invasive instrument called a bronchoscope to look inside a patient’s lungs and perhaps remove a tissue sample.

Carrado Di Natale, head of the e-nose development team, believes a super-sensitive version of the device might in future be used routinely to screen smokers and other high-risk groups for lung cancer.

”It would be less accurate than bronchoscopy but it would be so much easier,” he said.

But Richard Sullivan, head of clinical programmes at the charity Cancer Research UK is sceptical. He said: ”Smell is very important for detecting disease and this is an interesting twist. But this study is much too small to mean anything.”

He added that even a highly sensitive nose could only detect surface tumours, and would never replace the blood tests or scans which alert doctors to the onset of secondary cancers. – Sapa-DPA