Thousands of men suffering from advanced prostate cancer have been offered new hope of a cure after scientists discovered the genetic cause behind 90 per cent of tumours.
Nine out of 10 cases of late stage prostate cancer can now be linked to changes in the DNA of sufferers. In some cases, there are already drugs to tackle those genetic defects which are being used for other cancers.
Scientists said the breakthrough was like uncovering the "Rosetta Stone" for prostate cancer, in reference to the stone tablet which helped Egyptologists break the code of hieroglyphics. The research was hailed by charities as "incredibly exciting".
The study was led in the UK by scientists at The Institute of Cancer Research, London, in collaboration with researchers from eight academic clinical trial centres around the world.
Researchers said that doctors could now start testing for the mutations and give patients with advanced prostate cancer existing drugs or drug combinations which are known to target the specific genomic aberrations.
"Our study shines new light on the genetic complexity of prostate cancer as it develops and spreads, revealing it to be not a single disease, but many diseases each driven by their own set of mutations," said Johann de Bono, professor of experimental cancer medicine at The Institute of Cancer Research, London, and consultant at The Royal Marsden in London.
"We're describing this study as prostate cancer's Rosetta Stone - because of the ability it gives us to decode the complexity of the disease, and to translate the results into personalised treatment plans for patients."
Nearly 50,000 men are diagnosed with prostate cancer each year in the UK and more than 10,000 will die from it.
Doctors from the Royal Marsden and hospitals in the US studied the genetic make-up of 150 tumours from patients with advanced prostate cancer and a slim chance of survival.
Nearly two thirds of the men in the study had mutations in a molecule that interacts with the male hormone androgen which can already be targeted by current drugs.
Around 20 per cent of patients also had mutations in the BRCA1 and BRCA2 genes. They are known to raise the risk of breast and ovarian cancer and there are already drugs to help.
The researchers also found for the first time that some people are born with genes which predispose them to prostate cancer, meaning that screening programmes could be effective at preventing the disease. Professor Paul Workman, chief executive and president of The Institute of Cancer Research, London, said: "These findings could make a real difference to large numbers of patients."
In the next phase of the study, researchers will genetically sequence tumour cells from at least 500 patients and follow the course of their disease to see how they respond to personalised treatments.
Charities described the work as ground breaking and said it was particularly exciting because changes to treatment could happen almost immediately.
Dr Iain Frame, Director of Research at Prostate Cancer UK said: "This is incredibly exciting and ground breaking research. It suggests for the first time the list of genetic mutations to search for in order to build up a blueprint of a man's prostate cancer once it has spread."
The research was published in the journal Cell.