Small-molecule volatile organic compounds (odorants) in urine may be useful in diagnosing lung cancer at an early stage, according to results of a mouse study by scientists at the Monell Chemical Senses Center, the Panasonic Corporation, and the University of Pennsylvania. These molecules, which can be perceived as odors (especially by animals), have been shown to function as “signatures” that convey social, emotional, and health information to other members of the species. The results of other studies support the hypothesis that odorants can be detected in the breath of lung cancer patients by smell (dogs were trained to do this, for example) or through bioanalytical techniques such as solid-phase microextraction followed by gas chromatography. Analysis of breath samples, however, is cumbersome and technically challenging, thus limiting its applicability. Lung cancer is the leading cause of cancer-related deaths throughout much of the world, and the only treatment with a high rate of cure is surgical resection of early disease (before metastatic spread occurs). Because only about 25 percent of cases are diagnosed at this early stage, effective early diagnostic techniques are urgently needed. In the current study, the scientists demonstrated that mice can be trained to discriminate between urinary odors of mice with and without experimental lung tumors, demonstrating that odorants are sufficient to identify tumor-bearing mice. Consistent with this result, chemical analyses of urinary odorants demonstrated that the amounts of several compounds were dramatically different between tumor and control mice. These chemical analyses were carried out using solid-phase microextraction followed by gas chromatography combined with mass spectrometry.Login Or Register To Read Full Story