A study of the volatile organic compounds exhaled by lung cancer cells in vitro for breath diagnosis

Abstract BACKGROUND. The specific volatile organic compounds (VOCs) exhaled by lung cancer cells in the microenvironment are the source biomarkers of lung cancer and also serve as direct evidence that the diagnosis of lung cancer by breath is possible. However, to the authors' knowledge, few articles published to date have provided accurate VOCs in the microenvironment, thereby leading to different points of view with regard to searching for biomarkers in the breath from lung cancer patients In this article, an innovative pathologic analysis method of lung cancer and the early diagnosis of lung cancer at the cellular level were introduced for this purpose. METHODS. Solid‐phase microextraction combined with gas chromatography is used as the detection system to determine the VOCs in the culture medium of several target cells, including different kinds of lung cancer cells, bronchial epithelial cells, tastebud cells, osteogenic cells, and lipocytes. As a result, each kind of cells has a unique chromatogram. There are 4 special VOCs that were found to exist in all culture mediums of lung cancer cells, which are the metabolic products of lung cancer cells and can be viewed as markers of lung cancer. RESULTS. The authors were able to determine a correlation between VOCs in the metabolic products of lung cancer cells and VOCs in the breath of lung cancer patients, some of whom had stage I and II disease, and eventually hope to certify the biomarkers in the breath of lung cancer patients. CONCLUSIONS. This research is significant and provides the basis for the noninvasive detection and the breath diagnosis of lung cancer using an electronic nose. Cancer 2007; 110:835–44. © 2007 American Cancer Society.