My expertise is in breast cancer, in particular how to use the biology of the disease to improve the choice for treatment for patients. So first of all who is high risk of recurrence versus low risk of recurrence which you can read in the tumour looking at the aggressiveness of the biology, which I actually developed a test called the 70-gene prognosis signature, also known as MammaPrint, where we did a huge European trial to show that patients who are clinically high risk but MammaPrint low risk can safely forego chemotherapy. So that actually with the group from the European Organisation of Research and Treatment of Cancer we did a trial in 7,000 patients providing that evidence which actually could save up to 40,000 women per year in Europe chemotherapy that they would not benefit from. So that’s one aspect of my work, the other one is that if patients are high risk of recurrence you would want to give them the best treatment. Then my expertise as being a molecular biologist comes in again to look again under the hood of the tumour and see whether the engine in that tumour, besides being aggressive, what are actually the characteristics. So are we dealing with a fast race car which is of brand type A or brand type B and we may have a treatment that if we want to stop that car that would actually block car type A from driving fast and another one for driving fast for the brand type B. So that’s actually where we are in the last 25 years that I’ve been working on this to improve diagnostics of breast cancer in particular to understand who is at risk for recurrence and if you are at risk what is the biology that can help us to decide on the best treatment.
Can you tell us more about this technique?
Looking under the hood of the tumour, that’s a biology you can do in different ways, every cell and every tumour cell has active genes. Gene activity you can measure by looking at the messenger RNA. So we’ve been looking at gene expression which is a different way of saying messenger RNA; we’ve been looking at the gene activity by looking at the gene expression and seeing which genes are active in a tumour where a woman has a high risk of recurrence versus where the tumour and the patient has a low risk of recurrence. It turned out that 70 genes that were either expressed in the on status or in the off status would determine the high risk of recurrence versus the low risk of recurrence. So what we did is pattern recognition of gene expression by technology called microarrays and nowadays more something like, if you’ve heard of it, RNA sequencing is used.
What are the potential clinical implications to your findings to date?
For the 70-gene prognosis signature, MammaPrint, we achieved level 1a evidence. So that’s now more and more into guidelines and it’s reimbursed by insurance companies. So that’s taking its own path being implemented. My other work is in understanding who has tumour biology type A or B so that we can match the most effective treatments to every patient based on her tumour characteristics. There we are in the evaluation trial phase but hopefully that will lead soon to diagnostics that can also help to determine what is the best type of therapy.
How do you see breast cancer treatment changing over the next 10 years?
In particular the molecular basis of cancer will drive the treatment choices. Over the last maybe 15-20 years that I’ve been working on this topic, where it used to be only looking through the microscope and defining a number of characteristics, now we’re really looking under the hood of the tumour to look at how is the wiring and what is active and what is not active and that will determine the treatment. So it’s more and more precision medicine, personalised medicine, as we would hope we can achieve which, of course, goes in steps. We have not that available for everybody at once but more and more we understand what patients can already benefit from treatments that are targeted, so to speak, today and more in the future.
What is your take home message?
Since biology, and molecular biology in particular, starts to play such a central role one of the important things is actually education. Education of what is available and how should we value what is actually currently available and how should we design the trials to get new knowledge. So meetings like the IMPAKT meeting are actually crucial to help a broad audience understand what’s going on and get actually that level of education higher.
