Personalised treatments for the deadliest cancers could be on the horizon after scientists discovered what makes them grow and spread.
They are fuelled by a phenomenon dubbed 'chromosomal instability' - making them particularly aggressive.
Now an analysis of 7,880 tumours - representing 33 forms of the disease - has identified 17 different types of the process.
The 'signatures' predicted how they would respond to drugs - and also established future potential medications.
Lead author Dr Florian Markowetz, of the Cancer Research UK Cambridge Institute, said: "The more complex the genetic changes that underlie a cancer, the more difficult they are to interpret and the more challenging it is to treat the tumour.
"This is tragically clear from the very low survival rates for cancers that arise as a result of chromosomal instability.
"Our discovery offers hope that we can turn things around, providing much more sophisticated and accurate treatments."
Survival rates in these cancers are often less than ten percent. The breakthrough could revolutionise therapy.
DNA is packaged up into sets of chromosomes containing thousands of genetic instructions.
The study found tumours with more 'chromosomal chaos' - the ability to alter thousands of genetic instructions - were the most aggressive.
They develop resistance to chemotherapy drugs, can hide from the immune system - and move to other tissues in the body.
By understanding chromosomal instability, the international team can find ways to stop it.
Dr Markowetz said: "With Tailor Bio, we are now working hard to bring our technology to patients and develop it to a level where it can transform patients' lives."
The spin-out company aims to build a new pan-cancer precision medicine platform - leading to better drugs for a wide range of cancers.
Patients will be grouped according to their cancer type more accurately - ensuring the the best, most targeted treatment.
Using data from The Cancer Genome Atlas, the researchers looked for variations in the the number of DNA repetitions of given sequences or regions.
The findings provide the first 'framework' to interpret larger, more complex patterns of genetic changes seen in chromosomal instability.
Our genetic code is stored on 23 pairs of chromosomes, the 'chapters' that make up to the genome.
When it gets copied, they can become unstable. Segments of DNA get duplicated, deleted or re-arranged.
Chromosomal instability is a common feature of cancer - occurring in around 80 percent of cases.
The jumble of fragments are difficult to read in any given tumour. Instead, tumours are categorised broadly has having high or low chromosomal instability.
The study in the journal Nature helps untangle them - opening the door to improving outcomes for millions of patients worldwide.
Dr Markowetz said: "The signature compendium presented here is an important resource to guide future studies into a deeper understanding of the origins and
diversity of chromosomal instability and how to therapeutically target different types."
