Analysis of exhaled breath with chromatography or electronic nose. Diagnosis of lung cancer by

multifactorial logistic regression analysisDr.med. Māris Bukovskis 1 2 4, Dr.biol. Gunta Strazda 1 2 3, Dr.med Uldis

Kopeika 2 5, Dr.biol.Normunds Jurka 2, Līga Balode 2, Dr. Jevgenija Aprinceva 3, Dr. Ainis Pirtnieks 5, Prof. Immanuels Taivans 2 3

1 Department of Pulmonology and Allergology, Pauls Stradins Clinical University Hospital, 2 Institute of Experimental and Clinical Medicine, University of Latvia, 3 Faculty of Medicine, University of Latvia, 4 Department of Internal Medicine, Faculty of Medicine, University of Latvia, 5 Department of Thoracic Surgery, Pauls Stradins Clinical University Hospital

Lung cancer mortality and diagnostic methods• Lung cancer is the leading cancer killer in both men

and women and causes more deaths than the next three most common cancers combined (colon, breast and prostate)

• 58 - 73% of stage I lung cancer patients suvive 5-years compared to 9 - 24% of patients with stage III lung cancer

• Available diagnostic methods - nonsensitive (sputum, chest x-ray), expensive (CT) or invasive (FB)

Goldstraw P et al. J Thorac Oncol 2007American Cancer Society Cancer. Facts and Figures 2012

VOC’s in exhaled breath

Lung cancer sniffer dogsCBC News Aug 17, 2011

Gordon SM et al. Clin Chem 1985Machado et al. AJRCCM 2005

Chen X et al. Cancer 2007

Is this so easy?

Complex consisting of desorbtion unit, gas chromatograph and mass spectrometer

Chromatogram showing multiple peaks representing particular chemical substances

Time (s)

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Baseline

Response of 32 sensors to air sample

Functional principles of electronic nose

ΔRmax

Cyranose 320

Methods

• 475 patients in total, 252 of them lung cancer patients, and 223 patients with different lung diseases and healthy volunteers, were recruited in the study

• Collection and sampling of exhaled air by electronic nose (Cyranose 320)

• Analysis of “smell prints” by multifactorial regression analysis

ResultsClassification of cases in nonsmokers

Lung cancer No cancer

Lung cancer 128 12 PPV 91.4%

No cancer 5 120 NPV 96.0%

Sensitivity 96.2% Specificity 90.6%

Classification of cases in smokers

Lung cancer No cancer

Lung cancer 114 7 PPV 94.2%

No cancer 5 84 NPV 94.4%

Sensitivity 95.8% Specificity 92.3%

Why is this so valuable?

• Advantages of exhaled breath analysis by electronic nose: - cheap - easy to do - non-invasive - sufficiently accurate - possible to do in a large number of patients at risk (all

smokers > 50 years of age)

• Chromatography analysis is valuable for scientific research purposes

Thank You for Your Attention!

How to sniff out the disease?