Does lung cancer cause bad breath?

An interesting Oral Presentation given to us at the TSANZ & ANZSRS Annual Scientific Meeting held in Brisbane in March was a presentation called “Exhaled Breath Analysis Characterises Lung Cancer”. This was a study carried out by the Prince Charles Hospital in Brisbane and the University of Queensland.

They used an electronic nose (Cyranose 320) to measure volatile organic compounds (VOCs) in the exhaled breath of three groups of subjects; those who had lung cancer, smokers with a history of >30 pack years, and healthy non-smokers.

Their aim was to identify an exhaled breath VOC profile (‘smellprint’) in lung cancer subjects that discriminates from healthy non-smokers and smokers, aged 60-74 years.

Subjects performed two exhaled vital capacities (10 minutes apart) into a Tedlar sample bag after breathing tidally through an inspiratory port VOC filter for 5 minutes. The samples were analysed using a Cyranose 320.

Their results were that smellprints from lung cancer (n=8) and smoking subjects (n=13) were separated from normal subjects (n=21) with cross validated accuracy (CVV) of 75.9% (p = 0.006) and 97.1% (p <>

They concluded that VOC profiling of exhaled breath using an eNose distinguished healthy subjects from lung cancer and smoking subjects, and between the lung cancer and smoker group, and therefore that the eNose has the potential to be a diagnostic and screening tool for lung cancer.

Previous studies to support this idea have included Gordon (1985) who identified in the exhaled air of lung cancer patients several volatile organic compounds that appeared to be associated with the disease.

Phillips (2003) found that compared to healthy volunteers, patients with primary lung cancer had abnormal breath test findings that were consistent with the accelerated catabolism of alkanes and monomethylated alkanes. He found that a predictive model employing nine of these VOCs exhibited sufficient sensitivity and specificity to be considered as a screen for lung cancer in a high-risk population such as adult smokers.

Machado (2005) concluded that the exhaled breath of patients with lung cancer has distinct characteristics that can be identified with an electronic nose, and that his results provided feasibility to the concept of using the electronic nose for managing and detecting lung cancer.

Testing with an eNose would be a novel, simple, and non-invasive technique to diagnose lung cancer. I look forward to the results of further research.

Heather