Disease Detection By Dogs: A Knowledge Base For Everyone
The Institut Curie in France is aiming with the KDOG programme to develop a clear and effective methodology for cancer detection by dogs through 5 research programs, while ensuring it is repeatable, reliable and ethical, wherever it is implemented.
What does the project solve?
Kdog wants to develop a clear and effective methodology for medical detection by dogs through 5 research programs, while ensuring it is repeatable, reliable, and ethical, wherever it is implemented.
Breast cancer is the most prevalent cancer occurring in women, with 1 in 9 women being affected and more than 2 million cases per year. Timely screening increases chances of survival. However, many women do not have access to life saving screening facilities. This is due to various reasons including poverty, disability, isolation, and lack of medical resources. The World Health Organisation has reported that breast cancer is the cause of 15% of cancer related deaths in women, and we believe this number is far too high.
Institut Curie researchers hypothesize that V.O.C. (Volatile Organic Compounds), and associated odors, could be a biomarker of breast cancer. Undetectable for the human nose, two methods would allow the identification of these characteristic odours: analytical chemistry and detection by canine odorology.
Dogs have a sense of smell 100,000 to 1 million times more sensitive than humans. This means properly trained in scent detection, dogs could be able to detect the characteristic odour of a cancerous tumour in body fluids such as sweat, helping to support early detection methods.
Using dogs to detect various diseases is an idea that has grown in just a few years from the realm of « fantasy » to recognition by the scientific community. The KDOG programme, led by the Institut Curie in France has been part of this movement since 2016.
In 2016 and 2017, KDOG Team started a preliminary study. The results were more than encouraging evaluated on samples that were unknown to them, the dogs had a success rate of 90.3% in the first round! This proof of concept was presented at the Academy of Medicine on February 21, 2017.
The KDOG team have come up with a technique for breast cancer screening which is still under scientific study. In 2018, KDOG started the clinical trial in order to see, in a longer time, if the results would stay encouraging. Here is the basis of the clinical trial: This process sees the individual place a compression on each breast overnight to absorb the sweat and bodily fluids which is then sent back via an envelope for analysis. The method is simple, painless and the dogs are never in contact with the patients.
Deep memorization phase: dogs learn to memorize the smell of breast cancer on compresses that have been directly in contact with a cancerous tumour.
Reduction of the threshold level: the dog continues to train with compresses covered in sweat which had previously come from a cancerous breast.
Case study: the « cancer » compress is placed in the middle of « healthy » compresses.
The dog learns to identify the difference between the negative samples and positive samples.
The dog works in complete autonomy (without leash).
In 2019, the very first International Symposium sponsored by Royal Canin gathered 24 international teams in medical detection. The main conclusions admitted that the essentials of medical detection were not yet tackled and that there is a need in leading scientific excellence in this territory to help raise the bar.
The Institut Curie in France is aiming with the KDOG programme to develop a clear and effective methodology for cancer detection by dogs, while ensuring it is repeatable, reliable and ethical, wherever it is implemented. Thanks to the Royal Canin Foundation’s support, Institut Curie aims to develop a scientific toolbox with tools and protocols, certification training and guidelines in dog medical detection for scientific communities working on medical detection around the world.
The aim of the project is to LEAD the territory of Medical Detection by supporting 5 programs (« 5Ps ») that answer the 5 key questions that are today the blockers to scale up in medical detection programs with dogs throughout the world.
The goal: to offer teams who wish to engage in the detection of diseases (cancers, viruses bacteria, or others) a reliable basis of Essentials for building their work and increasing their chances of success.
The clinical study conducted in 2020-2022 has raised many questions, especially in terms of methodology to increase the performance of dogs in medical detection. How long can an odor be retained? Under what conditions? On which support to maximize the diffusion of the odor? The answers to these questions being absent from the scientific literature, KDOG has launched several research projects to strengthen the scientific basis concerning cancer detection by odorology.
P1 - Odor Conservation
The dog's sense of smell has been little used in the medical field, especially since few research has been conducted on the properties of odors related to medical conditions. In addition, the number of odorant compounds necessary for the discrimination as well as their nature is not known.
This program will allow to control the parameters of stability, longevity and quality of the odor during the transport and the analysis of the samples. It will also allow to clarify the nature of odorant characteristic of cancer in a given population.
The project was launched in 2022 and is led by Michelle Leemans, post-doc at UPEC.
Publication date of the study expected mid-2023.
A literature review has been completed and published. “Volatile organic compound analysis as a potential novel screening tool for breast cancer: a systematic review“, Leemans et al. 2022 Biomarker insights
P2 - Study of the sampling medium
Sweat analyzed by KDOG dogs is currently collected on a specific sampling medium: swabs. However, the quality of the samples depends, in part, on the properties of this material (capacity of absorption, conservation and release of odors).
This program, launched in 2022, aims to specify the ideal composition of the support, based on the chemistry of the materials, according to the biological substrate used. Ultimately, a solution dedicated to transcutaneous or urinary sampling of odors will be developed.
A review of the existing literature on this subject was carried out at the beginning of the project to establish the remaining questions. “Human odor capture devices for medical diagnosis.“ The anticipated publication date is early 2023.
The study is in progress and is being carried out by Pr E. Marchioni and D Steyer of the University of Strasbourg.
P3 - Canine olfaction
No study has yet specified the advantages and limitations of the use of canine olfaction in a medical setting compared to that of an electronic nose. To answer this question, two projects are being conducted:
- A threshold study, to estimate the minimum odor threshold at which the dog is able to discriminate VOC (Volatile Organic Compounds) found in cancer. This threshold study will be carried out under three conditions: in water for the objective threshold, then in artificial sweat and in urine for the threshold in real environment. Three of our dogs are working on the subject: Owen the Malinois, Prince the Springer and Nougaro the Labrador.
- A study of the brain activity of dogs by electroencephalography, in order to better understand the canine reflexes when faced with a smell, as well as the differences between dogs trained in odorology and so-called “naive“ dogs. This project will start at the end of 2022.
This asolutely painless protocol has been studied so that dog don’t feel any electrical impulse and validated by a clinical research ethics committee.
Ultimately, this program will allow us to refine the selection and training protocol of the dogs. It will also help us to optimize the use of samples and the training protocol of the dogs for breast cancer detection.
The study is in progress with Dr. Olivier Collin, Pr Caroline Gilbert from ENVA and Dr. Hind Baba Aïssa.
A review of the literature on the use of detection dogs in medical diagnosis has been carried out and is being published. “Remote medical scent detection of cancer and infectious diseases with dogs and rats: a systematic review.“ Leemans et al.
P4 - Certified Training in Medical Detection Dogs (CTMDD) Can-KDOG
The canine methods of disease detection require the assistance of dog handlers to train and accompany the dogs. Today, these dog handlers are first trained in the detection of drugs, explosives... However, the detection of diseases by dogs requires specific and plural competences, combining at the same time dog science, medical research and ethology.
The creation of a multidisciplinary training program for canine handlers in disease detection, in Europe and North America, would allow in the long term to improve communication between medical and canine teams, as well as to limit the human factor during the detection process and thus increase performance.
The program, currently being prepared, will be conducted by UPEC and the University of Montreal.
P5 - MOOC - How to conduct human research (for non-medical people)
The detection of diseases by odors, and in particular by canine odorology, is an emerging discipline. In fact, the methodologies used to establish preliminary and clinical studies lack rigor because they are based on scientific, medical and ethological foundations that are still uncertain.
Based on its experience, KDOG wishes to propose a list of guidelines that are legally, economically, medically and ethically appropriate for preliminary and clinical studies for the detection of disease by odorology. This methodological base would be accessible to all research teams in the field and would thus accelerate research on this subject.
We will be assisted by the ENVA and the UPEC to make this project a reality. It is, for the moment, still being prepared.
The detection of diseases by dogs, in particular cancer, is an unconventional method, not well known and still rarely used (never, in the case of cancer). It is therefore necessary to collect the opinion and the reaction of patients to this innovation.
This study therefore aims to measure the level of acceptance of this type of diagnosis, to understand possible fears, and to listen to practical expectations. It will thus be possible to propose a method that is accepted, adapted to the field and to cultural sensitivities, and, finally, accepted.
This study is led by Marion Sangle-Ferriere, lecturer at the University of Cergy Pontoise. The qualitative study will end in December 2022 and the quantitative study mid-2023.
Previous KDOG publications:
- “A New Transcutaneous Method for Breast Cancer Detection with Dogs“, Thuleau et al. 2019, Oncology.
- “Volatile Organic Compounds of Malignant Breast Cancer Wounds: Identification and Odors“, Thuleau et al. 2018, Wounds