Our senses have always been an important tool in detecting whether something is wrong, and especially when it comes to health. Perhaps sight, sound and touch are the most relevant in this sense, but a colleague of mine recently brought to my attention a review on the detection of cancers using the ‘electronic nose’1.
The concept itself is not new, with one doctor writing to The Lancet as far back as the late 1980s with an anecdote about a patient whose dog had sensed the cancerous cells in its owner. Since then, there have been a plethora of papers investigating this phenomenon and how the medical community might be able to harness the power of olfaction as a diagnostic tool.
Indeed, in an article published in the European Respiratory Journal in 20092, a group of researchers in Germany found that trained dogs could detect a tumour in 71% of patients. The more recent review1 explains that cancer cells actually leave behind clues of their presence, much like a fingerprint at a crime scene, with mainstream techniques harnessing image-based diagnostics. However, this can be costly and sometimes invasive — never a pleasant experience for the patient who is already uncomfortable and stressed at the thought of possibly having a life-threatening disease. Cue a study in 19993, which investigated the use of gas chromatography analysis of exhaled breath to diagnose lung cancer — exhaled breath was considered to carry information about the health of the body — and the development of artificial olfaction.
Much research has investigated this innovative method of cancer detection, which has been found to detect lung cancer, prostate cancer, breast cancer and even colorectal cancer to date.
All of this research provides some exciting opportunities for the future of oncology medicine and research, as it is well known that the earlier one can detect cancer, the better the prognosis for the patient. I imagine that, if harnessed correctly and effectively, one will simply be able to visit the GP for a routine check-up and cancer check to boot; much like attending the asthma clinic for a peak-flow test.
However, the electronic nose does not represent a solution as yet, but is only a support for non-invasive cancer detection at present, and further research is still needed in order to improve performance of this diagnostic tool, but the future is promising.
1. D’Amico A, Di Natale C, Falconi C et al. Detection and identification of cancers by the electronic nose. Exp Opin Med Diagn 2012; 6(3): 175–85
2. Horvath I, Lazar Z, Gyulai N et al. Exhaled biomarkers in lung cancer. Eur Respir J 2009; 34(1): 261–75
3. Phillips M, Gleesson K, Hughes JMB et al. Volatile organic compounds in breath as markers of lung cancer: a cross-sectional study,lancet 1999; 353: 1930–3