A huge step towards one of the biggest goals in medicine has been taken, with the development of a universal blood test for cancer. 

Scientists at Johns Hopkins University has trialed a method that detects eight common forms of the disease. Their intention is to have an annual test designed to catch cancer early and save lives. 

Costing less than $500 (£360) per patient, the test known as the CancerSEEK, looks for mutations in 16 genes that regularly arise in cancer and eight proteins that are often released. The results of which detected 70% of the cancer. 

Dr. Cristian Tomasetti, from Johns Hopkins University School of Medicine, explained, “This field of early detection is critical. I think this can have an enormous impact on cancer mortality.”

The idea is that the earlier the cancer is found, the greater the chance of being able to treat it. Five of the eight cancers investigated have no screening programmes for early detection. 

Pancreatic cancer can be very difficult to detect as there are often so few symptoms, resulting in four in five patients dying in the same year that they are diagnosed. 

Reported in the journal Science, the test is novel because it hunts for both the mutated DNA and the proteins. Increasing the number of mutations and proteins being analysed would allow it to test for a wider range of cancers. 

“This is of massive potential,” commented Dr Gert Attard, team leader in the Centre for Evolution and Cancer at the Institute of Cancer Research, London, and consultant medical oncologist at the Royal Marsden NHS Foundation Trust. 

“I’m enormously excited. This is the Holy Grail, a blood test to diagnose cancer without all the other procedures like scans or colonoscopy.”

He continued to explain that “we’re very close” to using blood tests to screen for cancer as “we have the technology.”

However, he did express that there is still uncertainty surrounding what to do when a cancer was diagnosed. In some cases, the treatment may be worse than living with a cancer that is not immediately posing a threat to life. 

“When we detect cancer in a different way, we can’t take for granted that everyone will need treatment,” he added. 

Although this is tremendously exciting, more work is needed to assess the test’s effectiveness at detecting early-stage cancer. 

Professor Richard Marais, from Cancer Research UK, said it would take at least five to six years to prove that it worked as an early diagnosis for cancer. 

“They looked at healthy people – well, if you’ve got a cold or flu or other underlying condition, how will that affect the test?” he noted. 

In addition, Paul Pharoah, professor of cancer epidemiology at the University of Cambridge, said more work was needed to assess how the test performs when cancers are less advanced. 

“Demonstrating that a test can detect advanced cancers does not mean that the test will be useful in detecting early stage symptomic cancer, much less pre-symptomatic cancer. The sensitivity of the stage 1 cancers in the study was only 40%.”

Despite more work being required before the test can be used to its full potential, such progress is still very exciting, and proves just how fast the field is developing.