A major study has revealed a new chemotherapy drug which extends the lives of patients with advanced prostate cancer by nearly 2 years.

Experts said the findings from a trial in Britain and Switzerland were "potentially game-changing", BBC reports.

During the trial, which was run across Britain and Switzerland, 2,962 men took part in the trial and some were given 6 doses of docetaxol at the start of their treatment.

Docetaxel is normally given after hormone treatment has failed, but results, to be presented at the American Society of Clinical Oncology, will show earlier treatment can extend life expectancy from 43 to 65 months.

Speaking on the discovery, Prof Nicholas James, who was one of the researchers at Warwick University, called for all patients with prostate cancer that had spread to be given docetaxel when they are diagnosed, saying he was very pleased with the success ratio.

One of the recipients of the treatment, 77-year old John Angrave said he had been given 3 to 5 years to live - that was 7 years ago.

However, researchers have said they need to monitor patients for longer to see if the drug significantly prolongs life if the cancer has not spread.

They also added that though there were side effects from the treatment, they were however "manageable".

Describing the trial discovery as game-changing, Dr Iain Frame, the director of research at Prostate Cancer UK, said:

"Chemotherapy is currently one of the last-resort treatments for advanced prostate cancer. If it is shown to have a much greater impact on survival when prescribed earlier and alongside hormone therapy, that's incredibly exciting, and we would want to see this brought in to the clinic so it can benefit men without delay."