Catching cancer early, before the disease has spread, is one of the most powerful ways to improve cancer survival. But to revolutionise the way we diagnose and treat cancer, we need to change the focus and process of research.
The largest challenge in detecting cancer early is knowing what to look for. Cancer is usually diagnosed after people present with symptoms; a lump they can feel, a chronic cough, blood in their stool. Often, by the time these symptoms appear, the disease is already at an advanced stage. Most cancer research, in both universities and the private sector, has focused on this later-stage disease.
For many cancers, because they evolve over time, we don’t know what early-stage disease looks like, let alone what to test for to detect it. To increase survival, the ability to detect the disease at its early onset is vital; earlier treatment is significantly more effective.
The challenge of early detection of cancer is momentous; tumours at their earliest stage are a fraction of the size of a grain of sand. Scientists often try to detect tumours using biomarkers, molecules made by tumours, which normal cells do not produce or produce at lower levels.
The problem is that the tiny amounts of biomarker produced by an early tumour are dwarfed by the much higher amounts of the tens of thousands of molecules routinely produced by normal cells. The proverbial needle in a haystack. Except it’s worse than that as the biomarker you are looking for may actually be very similar in structure to hundreds of normal, healthy molecules – you’re actually looking for one special strand of hay in a haystack.
A further challenge is to ensure that detection technologies also tell us about how aggressive the disease is likely to be. This will then help deliver the appropriate manner and level of treatment.
The good news is that our biological understanding of cancer has grown over the decades and technology has advanced hugely, providing opportunities for research we never had before. This means we’re at a turning point that researchers need to take advantage of and must act now.
Scientists need to work across disciplines, bringing together the best minds and most novel concepts from chemistry, physics, engineering, mathematics and computer science, alongside biomedical experts. It’s only through this collaboration that we’ll be able to develop new technologies to find the incredibly small signals emitted by early tumours and to extract these signals from the sea of normal, healthy biological molecules.
Biologists have made incredible advances in helping us understand the early events in cells which cause them to become cancerous. The research community now needs to apply this biological insight to the clinic. Tests must be developed with the health service in mind to accelerate health improvements.
Cancer Research UK is in a unique position to have oversight of the development of early-detection tests and technologies from driving basic biology, seeing it through clinical testing and influencing policy to ensure tests are implemented in the NHS.
The charity’s aim is to build a critical mass of research in the UK, drawing together these fragmented strengths and resources, galvanising the research community to tackle these challenges, and engaging industry to make sure advancements make their way to the clinic.
Cervical screening and the bowel screening programme are great examples of early detection on a population scale which have saved a great many lives. But much more work is needed, especially for hard-to-treat cancers, such as brain, pancreatic, oesophageal and lung, where survival remains stubbornly low.
The ultimate goal is to develop tests that help doctors diagnose patients when they have the best chance of surviving their disease and give more patients the all clear. Cancer Research UK’s ambition is that three in four people will survive cancer by 2034; early detection will be essential in realising that ambition and, with the help of the generosity of our supporters and the brilliance of our scientists, it is within reach.
By Dr David Crosby, head of early detection at Cancer Research UK