The page has links to medical studies that have been completed by trainers and doctors collaborating in the past several years. You can read the entire documents, or just the overviews presented, in order to see the amazing results for yourself.
Canine scent detection of human cancers: A review
of methods and accuracy
"Early detection of cancers, although essential for treatment effectiveness, can be difficult to achieve, and some tests introduce additional health risks. New, non-invasive detection methods with greater sensitivity and specificity are needed. Several authors have published research suggesting that dogs may be able to detect lung, breast, prostate, ovarian, and melanoma cancers by smelling skin lesions, urine, exhaled breath, and surgically extracted tumors.... Two studies involved dogs detecting breast cancer (sensitivity 88% using exhaled breath and 22% using urine; specificity was 98% and 20%, respectively), 1 involved bladder cancer (41% of urine samples detected), 1 involved melanoma (75–85.7% of in situ tumors detected), 1 involved lung cancer (sensitivity 99% and specificity 99% using exhaled breath), 1 involved ovarian cancer (sensitivity 100% and specificity 97.5% using thawed frozen tumor samples), and 1 involved prostate cancer (18% of urine samples detected)."
Diagnostic Accuracy of Canine Scent Detection in
Early- and Late-Stage Lung and Breast Cancers
"Lung and breast cancers are leading causes of cancer death worldwide. Prior exploratory work has shown that patterns of biochemical markers have been found in the exhaled breath of patients with lung and breast cancers that are distinguishable from those of controls....The diagnostic accuracy data reported were obtained solely from the dogs’ sniffing, in double-blinded conditions, of these breath samples obtained from subjects not previously encountered by the dogs during the training period....Among lung cancer patients and controls, overall sensitivity of canine scent detection compared to biopsy-confirmed conventional diagnosis was 0.99 (95% confidence interval [CI], 0.99, 1.00) and overall specificity 0.99 (95% CI, 0.96, 1.00). Among breast cancer patients and controls, sensitivity was 0.88 (95% CI, 0.75, 1.00) and specificity 0.98 (95% CI, 0.90, 0.99). Sensitivity and specificity were remarkably similar across all 4 stages of both diseases."
Cancer odor in the blood of ovarian cancer
patients: a retrospective study of detection by
dogs during treatment, 3 and 6 months afterward
"In recent decades it has been noted that trained dogs can detect specific odor molecules emitted by cancer cells. We have shown that the same odor can also be detected in the patient's blood with high sensitivity and specificity by trained dogs.... In Series I, one drop of plasma from each of 42 ovarian cancer patients (taken between the fifth and sixth courses of chemotherapy) and 210 samples from healthy controls were examined by two trained dogs. All 42 patients in Series I had clinical complete responses, all except two had normal CA-125 values and all were declared healthy after primary treatment. In Series II, the dogs examined blood taken from a new subset of 10 patients at 3 and 6 months after the last (sixth) course of chemotherapy. In Series I, the dogs showed high sensitivity (97%) and specificity (99%), for detecting viable cancer cells or molecular cancer markers in the patients' plasma. Indeed, 29 of 42 patients died within 5 years. In Series II, the dogs indicated positive samples from three of the 10 patients at both the 3- and 6-month follow-up. All three patients had recurrences, and two died 3--4 years after the end of treatment. This was one of the most important findings of this study.
Olfactory Detection of Prostate Cancer by Dogs Sniffing Urine:
A Step Forward in Early Diagnosis
"To evaluate the efficacy of prostate cancer (PCa) detection by trained dogs on human urine samples.....A Belgian Malinois shepherd was trained by the clicker training method (operant conditioning) to scent and recognize urine of people having PCa......The dog completed all the runs and correctly designated the cancer samples in 30 of 33 cases. Of the three cases wrongly classified as cancer, one patient was rebiopsied and a PCa was diagnosed. The sensitivity and specificity were both 91%.....This study shows that dogs can be trained to detect PCa by smelling urine with a significant success rate."