According to new research published in the European Respiratory Journal, sniffer dogs could be used for the early detection of lung cancer, Researchers from the Schillerhoehe Hospital in Germany were the first to discover that sniffer dogs can reliably detect lung cancer.

Lung cancer, the second most frequent form of cancer in men and women across Europe and the most common cause of death from cancer worldwide, claims over 340,000 deaths per year.

Lung cancer does not reveal any symptoms and early detection is therefore often by chance. Because current methods of detection are unreliable, scientists have been examining the use of exhaled breath specimens from patients for future screening tests. The method identifies volatile organic compounds (VOCs) that are associated to the presence of cancer.

Even though various different technological programs have been developed, this method is still difficult to apply in clinical settings, as it requires patients not to eat and smoke prior to testing. Additionally, the sample analysis can be slow with a high risk of interference.

For these reasons, no lung cancer-specific VOCs has been developed to-date.

This new study was designed to examine whether sniffer dogs could be used to identify a VOC in the breath of patients. Using dogs with specific training, researchers conducted a study comprising of 220 participants, including lung cancer patients, chronic obstructive pulmonary disease (COPD) patients and healthy volunteers.

The researchers conducted a series of tests to evaluate whether the dogs were capable to reliably identify lung cancer compared with healthy volunteers, volunteers with COPD and whether the results were still detected with the presence of tobacco.

The result revealed, that the dogs managed to correctly identify 71 samples with lung cancer out of a possible 100 and also successfully detected 372 samples that did not have lung cancer out of a possible 400.

The dogs were able to detect lung cancer independently from COPD and tobacco smoke and therefore substantiate the method as a valid indicator for lung cancer that is independent of COPD and also detectable in the presence of tobacco smoke, food odors and drugs.

In a concluding statement, Thorsten Walles, author of the study, from the Schillerhoehe Hospital said:

“In the breath of patients with lung cancer, there are likely to be different chemicals to normal breath samples and the dogs’ keen sense of smell can detect this difference at an early stage of the disease. Our results confirm the presence of a stable marker for lung cancer. This is a big step forward in the diagnosis of lung cancer, but we still need to precisely identify the compounds observed in the exhaled breath of patients. It is unfortunate that dogs cannot communicate the biochemistry of the scent of cancer!”

Written by Petra Rattue