SOUNDS OF SUMMER - Fighting Cancers
First broadcast: 11th August 2012
DESLEY BLANCH : A breath test using an electronic nose is sniffing out early stage malignant, asbestos-related cancers. Researchers at the University of New South Wales are designing a non-invasive test which would help detect and distinguish between benign and malignant disease.
The electronic nose is widely used to sniff out food contaminants and explosives and is now being modified to identify mesothelioma which globally kills up to 20,000 people each year.
Asbestos was widely used in Australia and Associate Professor Deborah Yates, the study’s team leader believes a breath test would be particularly suited for screening the old and infirm patients as well as the very young.
ASSOCIATE PROFESSOR DEBORAH YATES : We’re trying to develop something which is quick and easy for the patient and also which can be used in people who are elderly and quite unwell. Because it’s very difficult for patients to go through a whole load of different tests and also to go through the time that it takes to get all the results of those tests, not only physically but also psychologically. And, if we had something which was very easy to do and which we could repeat and which would have a high negative predictive value, in other words, not only have a very good positive predictive value which shows that the disease is there, but also a high negative predictive value which shows if the test is negative and there really isn’t a disease, then that would be very helpful to our patients.
DESLEY BLANCH : How easy is breath testing as a diagnostic tool, because mesothelioma is a disease that appears years later after that exposure to asbestos. So it must be horribly worrying for someone who knows they’ve had some exposure?
ASSOCIATE PROFESSOR DEBORAH YATES : It is, and it’s very, very easy as a diagnostic tool. I mean what we do at the moment is you get someone to breathe into our filter for five minutes and then we just get them to blow into a bag. So what we’re hoping to eventually have is a test which is rather like the breathalyser, where you count into something and you get a positive or negative diagnosis at the end.
DESLEY BLANCH : So is mesothelioma always malignant?
ASSOCIATE PROFESSOR DEBORAH YATES : It usually is. There is a very, very rare type called a benign pleural mesothelioma, but I have seen many, many people with mesothelioma and I’ve only seen one benign pleural mesothelioma. Probably in greater than 98% of them are malignant.
DESLEY BLANCH : So if this cancer can be detected early, can it be successfully treated?
ASSOCIATE PROFESSOR DEBORAH YATES : We hope so. We haven’t got any good evidence to show that at the moment. But I think what we need is better tests, so that we can actually intervene at an early period.
At the moment, the treatment involve surgery, radiotherapy and chemotherapy and all of them, in themselves, are I think, difficult for patients and I think we need a better method of treatment as well in the long run.
But having said that, the only way we’re going to get there is by actually understanding more about the disease and diagnosing it earlier, so we can offer people the appropriate treatment that we currently have.
There is a lot of research now looking at the molecular basis, the underlying genetic and cellular changes in mesothelioma and if we could identify the appropriate target and develop the right sort of drug, then we might well be able to help people as has occurred with other types of lung cancers, specific types of lung cancers where we know that there’s a specific molecular change and we can target that with a particular drug.
So the answer is, no at the moment, but hopefully in the future.
DESLEY BLANCH : Well you and your fellow researchers have trained this CyraNose. So what was your training process?
ASSOCIATE PROFESSOR DEBORAH YATES : We don’t know what the compounds are that are being measured by the CyraNose.
What we do is we show the Nose people with mesothelioma and we say, right, this is what we want you to pick up, so we take the breath from these patients and then we say this is what we’re looking for.
And the CyraNose has 32 chemical sensors and what they are is polymers which change slightly in their configuration. So what it picks up is a breath fingerprint and then what we do is we match the breath fingerprint to other types of disease and see whether the Nose can actually distinguish between them.
DESLEY BLANCH : This was a fairly small study and in that you obtained 88 per cent accuracy, so what needs to be done to improve that result?
ASSOCIATE PROFESSOR DEBORAH YATES : Well, we really need to do a much larger study in order to ensure that our findings were valid in the first place and also in order to be able to see how well the nose performs in the clinical setting, so in someone who is actually a normal human being who occasionally gets things like flu, who occasionally get other things going on, who has a whole load of different drugs that they’re taking, all of those things, because, of course, research studies are very selected patients.
So what we need to do is a large study where we look at people prospectively, in other words we look at them before they develop the disease and, we compare the performance of the Nose with other conventional tests and also with things like blood biomarkers, other biomarkers that are currently being developed.
DESLEY BLANCH : Do you think it’s going to be possible to continue using your breath test to check on the progress of treatments of the disease as it progresses?
ASSOCIATE PROFESSOR DEBORAH YATES : That’s our aim. We don’t have any information on that as yet, but we are hoping to be able to monitor people’s disease and also their response to treatment by using this sort of methodology.
With the current breath tests we may not be able to do exactly that, because it just recognises whether you have it or you don’t have it. But we’re developing another one which hopefully will be able to actually look at the levels of the different volatile organic compounds in order to look at response to treatment. So that’s our ultimate aim, although we haven’t got any information about our current breath test in that regard.
DESLEY BLANCH : And do you think it might transfer to detecting other cancers or would it be restricted to perhaps cancers based only in the lungs?
ASSOCIATE PROFESSOR DEBORAH YATES : Well it’s actually already being done for other cancers by other groups. Breast cancer, for example and lung cancer is another one. It’s also being used in prostate cancer and there are groups all around the world that are working on this particular area. The Dutch in particular have been very forward thinking in this regard and they have looked at the number of different cancers and interestingly, a Dutch group who we actually know quite well have produced almost identical results to ours with mesothelioma.
The other area that we are working on is its use in other types of lung diseases, like asthma, emphysema and the rarer types of lung disease.
DESLEY BLANCH : So when would you hope the tests would be available?
ASSOCIATE PROFESSOR DEBORAH YATES : Well unfortunately, with research what happens is that for five or so years, one has to do things in a research setting to make sure that it’s appropriately evaluated and that it’s perfectly scientifically sound. So not at least for five years, may be even longer, depending on the regulatory authorities.
At the moment, it’s just a research tool, but obviously the more that we can do to study things quickly and the more international work that we can do to gain the numbers the quicker it will be available and I actually hope it will be available quite soon, because I think it has potential.
DESLEY BLANCH: Deborah Yates is Associate Professor at St Vincent’s Clinical School at the University of New South Wales where they are developing a new test to identify whether or not a patient has the asbestos-related disease of mesothelioma.