title: Exhaled volatile organic compounds in patients with non-small cell lung cancer: cross sectional and nested short-term follow-up study.
abstract: BACKGROUND
  Non-invasive diagnostic strategies aimed at identifying biomarkers of lung cancer are of great interest for early cancer detection. The aim of this study was to set up a new method for identifying and quantifying volatile organic compounds (VOCs) in exhaled air of patients with non-small cells lung cancer (NSCLC), by comparing the levels with those obtained from healthy smokers and non-smokers, and patients with chronic obstructive pulmonary disease. The VOC collection and analyses were repeated three weeks after the NSCLC patients underwent lung surgery.
  
  
  METHODS
  The subjects' breath was collected in a Teflon bulb that traps the last portion of single slow vital capacity. The 13 VOCs selected for this study were concentrated using a solid phase microextraction technique and subsequently analysed by means of gas cromatography/mass spectrometry.
  
  
  RESULTS
  The levels of the selected VOCs ranged from 10(-12) M for styrene to 10(-9) M for isoprene. None of VOCs alone discriminated the study groups, and so it was not possible to identify one single chemical compound as a specific lung cancer biomarker. However, multinomial logistic regression analysis showed that VOC profile can correctly classify about 80% of cases. Only isoprene and decane levels significantly decreased after surgery.
  
  
  CONCLUSIONS
  As the combination of the 13 VOCs allowed the correct classification of the cases into groups, together with conventional diagnostic approaches, VOC analysis could be used as a complementary test for the early diagnosis of lung cancer. Its possible use in the follow-up of operated patients cannot be recommended on the basis of the results of our short-term nested study.
authors: National Institute of Occupational Safety and Prevention Research Center, University of Parma, Via Gramsci 14, 43100 Parma, Italy. dpoli7@unipr.it
authors: Diana
authors: D
authors: Poli
authors: Paolo
authors: P
authors: Carbognani
authors: Massimo
authors: M
authors: Corradi
authors: Matteo
authors: M
authors: Goldoni
authors: Olga
authors: O
authors: Acampa
authors: Bruno
authors: B
authors: Balbi
authors: Luca
authors: L
authors: Bianchi
authors: Michele
authors: M
authors: Rusca
authors: Antonio
authors: A
authors: Mutti
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D001944:Breath Tests / Q000379:methods*; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000378:metabolism*; D003430:Cross-Sectional Studies; D045853:Exhalation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000378:metabolism* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009930:Organic Chemicals / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012907:Smoking / Q000378:metabolism; D013223:Statistics as Topic; D016896:Treatment Outcome; D014835:Volatilization
chemical_list: D014408:Biomarkers, Tumor; D009930:Organic Chemicals