ESMO 2010

Dr James Mackay – University College London, UK

The role of genetic testing within oncology

Thank you very much for giving me two minutes in ecancer.tv, I know you’re very busy rushing round ESMO. You are probably one of the leading people in the UK steering the clinical application of the new genetics, particularly in breast and ovary and so on. But there are problems, as there are bound to be in setting up a new sort of service; tell us about the problems.

The interesting thing is that the service was set up over the last few years essentially to deal properly with unaffected people who had cancer in the family. Therefore, the service was developed as a fairly cautious, low-volume, time-consuming service. Recently, with the introduction of the new type of drug called PARP inhibitors, what’s going to happen is we’re going to have to be able to offer testing to cancer patients quickly.

That’s BRCA1, BRCA2 testing, mutation testing?

BRCA1 and 2, yes, which currently takes eight to ten weeks in most laboratories; it can actually be done in the laboratory of Myriad Genetics in 21 days.

In Milan, by the way, it can be done in six working days, so that’s another complication for you.

So what we’re seeing is that there is major geographical variation in the turnaround times. Because this testing is now going to have therapeutic implications, it’s going to be important that that variation is reduced and the turnaround time will have to be reduced all over the place.

Interestingly, not only does the lab turnaround time have to be reduced, we have to develop a proper clinical service for the unaffected members of cancer patients who are offered testing. That’s essentially the strength of the traditional clinical cancer genetic service, that it has looked after these people very well, given them time to think, properly consider their options, all that sort of thing. That’s going to have to be compressed in time now because of the idea that we need testing quickly because of the PARP inhibitors.

And you’re taking counsel from the patients themselves? In terms of how to build this service better?

Yes. Interestingly, the patients have had quite a lot of input into this with regards to we want testing quickly. So I’m now working only in the private sector in London but I see a lot of patients who have come who want to be tested very, very quickly. In essence, they don’t really mind about the concept of do their relatives need to know at the moment; the want testing today. But interestingly, what we’re seeing is that in the old days patients didn’t mind too much whether they carried a mutation or not; now the concept is that if you carry a mutation, you get this great new drug so therefore those who don’t carry the mutation are disappointed that they don’t get access to the drug. So we have to set up the conversation prior to testing more carefully and not make it sound as if this drug is absolutely wonderful because then all we end up with is really disappointed people who are not eligible for it.

And of course there are nine PARP inhibitors to choose from and there is nobody yet, I suppose, who has even thought about planning a chemo-prevention study where you’re going to be taking people who are completely unaffected but they have the mutation and exposing them to PARP1 inhibitors. That’s a whole new area and some people think it’s unethical; I think it’s worth exploring, personally, what do you think?

Definitely, I’m a great believer, as you’re aware, in the whole concept of breast cancer prevention. We ran the highly successful IBIS-1 study but, disappointingly in some ways, that hasn’t translated into an alteration in clinical practice in Europe although the concept of the research was clear. I think it would be very exciting to have some sort of prevention trial in gene carriers and I know for a fact that the patients and patients’ families are very interested in that area. Although it’s a relatively small patient cohort, I think there would be great interest amongst them.

I think they would be very motivated too. Well we’ll have to talk between London and Milan, James, and see if you can set it up. Thank you very much indeed for giving me a couple of minutes.