Volatile organic compounds as biomarkers of bladder cancer: Sensitivity and specificity using trained sniffer dogs

Abstract

In a previous canine study, we demonstrated that volatile organic compounds specific to bladder cancer are present in urine headspace, subsequently showing that up to 70% of tumours can be correctly classified using an electronic nose. This study aimed to evaluate the sensitivity and specificity which can be achieved by a group of four trained dogs. In a series of 30 double-blind test runs, each consisting of one bladder cancer urine sample placed alongside six controls, the highest sensitivity achieved by the best performing dog was 73% (95% CI 55-86%), with the group as a whole correctly identifying the cancer samples 64% (95% CI 55-73%) of the time. Specificity of the dogs individually ranged from 92% (95% CI 82-97%) for urine samples obtained from healthy, young volunteers down to 56% (95% CI 42-68%) for those taken from older patients with non-cancerous urological disease. Odds ratio comparisons confirmed a significant decrease in performance as the extent of urine dipstick abnormality and/or pathology amongst the control population increased. Importantly, however, statistical analysis indicated that covariates such as smoking, gender and age, as well as blood, protein and /or leucocytes in the urine did not significantly alter the odds of response to the cancer samples. Our results provide further evidence that volatile biomarkers for bladder cancer exist in urine headspace, and that these have the potential to be exploited for diagnosis.

Reliability of Trained Dogs to Alert to Hypoglycemia in Patients With Type 1 Diabetes

“…[25][26][27][28] Methodologies for in-vitro training and testing of DADs for the detection of hypoglycemia are being refined. 3 This is the first study to assess trained dog alerts concurrently with blinded CGM.…”

Die Supernasen

“…Ebenso hohe Quoten wurden beim Darmkrebs erzielt [5]. Bei Blasenkrebs lagen die Tre erraten niedriger, mit einer Sensitivität um 70 % und einer Spezi tät von 60-90 % [6] Experten vermuten, dass die Hunde üchtige organische Verbindungen (Volatile Organic Compounds, VOC) erschnü eln, die von Krebszellen produziert, freigesetzt und über die Atemlu oder den Urin abgegeben werden. Erst kürzlich ist es japanischen Forschern gelungen, VOC-Muster von gesunden Lungenzellen und Lungenkrebszellen zu analysieren [7].…”

Re-Centering Multispecies Practices

“…In the first study [31], six dogs were trained to discriminate between urine from bladder cancer patients and urine from diseased and healthy controls; they were then asked to select one bladder cancer urine sample from six controls during a double-blind trial in which neither dogs or trainers knew the content of the samples; as a group the dogs had a success rate of 41%, with 54% for the most successful dog, against the 14% expected by chance. In more recent bladder cancer discrimination trials [30], thanks to improvements in experimental design, the dogs reached a performance of 73%. 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).…”