Canine scent detection in the diagnosis of lung cancer: revisiting a puzzling phenomenon

Abstract

Patient prognosis in lung cancer largely depends on early diagnosis. The exhaled breath of patients may represent the ideal specimen for future lung cancer screening. However, the clinical applicability of current diagnostic sensor technologies based on signal pattern analysis remains incalculable due to their inability to identify a clear target. To test the robustness of the presence of a so far unknown volatile organic compound in the breath of patients with lung cancer, sniffer dogs were applied.Exhalation samples of 220 volunteers (healthy individuals, confirmed lung cancer or chronic obstructive pulmonary disease (COPD)) were presented to sniffer dogs following a rigid scientific protocol. Patient history, drug administration and clinicopathological data were analysed to identify potential bias or confounders.Lung cancer was identified with an overall sensitivity of 71% and a specificity of 93%. Lung cancer detection was independent from COPD and the presence of tobacco smoke and food odours. Logistic regression identified two drugs as potential confounders.It must be assumed that a robust and specific volatile organic compound (or pattern) is present in the breath of patients with lung cancer. Additional research efforts are required to overcome the current technical limitations of electronic sensor technologies to engineer a clinically applicable screening tool.

Re-Centering Multispecies Practices

“…The latest (still unpublished) findings from ongoing work by MDD indicate that their dogs now achieve higher levels of accuracy in their detection, with one particular dog achieving a reliability of over 90% (on bladder and prostate cancer). This is consistent with findings from other research reporting sensitivities of over 90% for prostate [4], colorectal [1,27] and lung cancer [6]. While these statistics are encouraging, enhancements in cancer detection practices would help further increase the accuracy of such non-invasive cancer screening procedures.…”

Advances in the Early Detection of Lung Cancer using Analysis of Volatile Organic Compounds: From Imaging to Sensors

“…In double-blind conditions, this experimental result showed 99% sensitivity and 99% specificity in the correct identification of lung cancer patients and controls, which were similar to those observed across all 4 stages of the disease (McCulloch et al, 2006). In 2012, Ehmann et al reported that their study yielded high specificity (93%) and moderate sensitivity (71%) in the detection of lung cancer from healthy controls using specially trained dogs to detect breath samples (Ehmann et al, 2012). Although the specific constituents in human breath working in canine scent detection of lung cancer are still unknown, preliminary success with canine scent detection suggests that breath analysis is practicable in the early detection of lung cancer (Moser and McCulloch, 2010).…”

An overview of parasite-induced behavioral alterations – and some lessons from bats

“…After all, evidence is mounting that animals with strong olfactory sensibility can detect a variety of human diseases (e.g. Ehmann et al, 2012;Willis et al, 2004). The vertebrate major histocompatibility complex (MHC) provides a logical connection between the immune system and odor (Kwak et al, 2010).…”