Genetic "portraits" of cancer patients can improve survival by identifying personalised therapy targets, a study has shown.
A third of treated patients recruited for the Moscato trial experienced at least a 30% increase in progression free survival, meaning they lived longer without their condition worsening.
The aim of the trial was to see if analysing the DNA of tumour samples could really make a difference to the fate of cancer patients.
More than 1,000 patients were enrolled with a wide range of disease types including including lung, breast, head and neck, prostate, bladder, bowel and stomach cancer.
Those able to provide samples had their tumour DNA sequenced in the hope of finding mutations that might provide a response to specific drugs.
Lead investigator Professor Jean-Charles Soria, from the Gustave Roussy Cancer Campus in Paris, France, said: "The primary objective of the Moscato trial was to demonstrate that incorporating high-throughput gene sequencing and using it to make therapeutic decisions could improve the clinical outcome for at least 25% of advanced/metastatic cancer patients.
"Final results showed that 33% of patients had an improved survival.
"This is the first precision medicine trial to show that analysing a person's DNA improves treatment options for patients with late stage cancer.
"And these results are particularly exciting because in some cases we were testing experimental drugs, and found that we could slow down the growth of tumours in around one in five patients with advanced cancer."
In total, 411 patients - 49% of all those providing tissue samples - were found to have an "actionable target" within their genes.
Around half of these patients were treated with ad hoc personalised therapies.
Trial co-designer Professor Fabrice Andre, head of the Inserm U981 research laboratory in Paris, said: "This positive result is particularly remarkable because the Moscato trial (Molecular Screening for CAncer Treatment Optimisation) specifically excluded patients with well-established actionable targets for which approved and marketed targeted drugs are available."
Results from the study were presented at the Map (Molecular Analysis for Personalised Therapy) conference in London.
The improvements in progression free survival seen ranged between five and 32 months. The length of time it took for tumours to grow back was compared with outcomes seen after previous treatment.
Dr Rowena Sharpe, head of precision medicine at Cancer Research UK, which helped organise the Map conference, said: "This is an exciting time for precision medicine and personalised treatment.
"It's fantastic to see continued effort going into this area and it's important that we make the most of the data that we already have."