From European Respiratory Journal and Dr. Sam Girgis:

Researchers from Germany lead by Dr. Thorsten Walles have shown that dogs can accurately detect lung cancer in the breath samples from lung cancer patients.  The results of their research were published online before print in the European Respiratory Journal.  The researchers used four sniffer dogs to test for the presence of a volatile organic compound in the breath of patients with lung cancer.  There were two German shepherds, one Labrador retriever, and one Australian shepherd.  The dogs were trained to differentiate the breath pattern of patients with lung cancer from those of normal individuals and patients with chronic obstructive pulmonary disease (COPD).  Exhalation breath samples from 220 study volunteers that were healthy, confirmed to have lung cancer, or had COPD were used in the study.  The sniffer dogs were able to identify lung cancer with an overall sensitivity of 71% and a specificity of 93%.  Importantly, the researchers were able to show that the sniffer dogs were able to detect lung cancer independently from COPD, the presence of tobacco smoke, and food odors.

Future studies with focus on the identification of the diagnostic volatile organic compound and development of electronic sensor technologies to detect it.  Using these methods, it may one day be possible to replicate the ability of dogs to detect lung cancer and establish a cheap and widely available screening test for lung cancer.

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