A woman's chances of surviving early stage breast cancer could improve by a third if she is treated with a particular combination of drugs, research has found.
The drug is used to target breast cancers
Results from the largest trial of its kind in the world show that the right chemotherapy regime - which includes a drug called Epirubicin - can prevent breast cancer recurrence following surgery and reduce deaths from the disease.
Modern chemotherapy treatments usually involve a cocktail of drugs that work together to help prevent cancer recurrence.
Through clinical trials these combinations have been refined over the years and survival rates have gradually improved.
It's incredibly rare to get such a significant increase by using existing drugs in a slightly different way
But researcher Dr Chris Poole, from the Cancer Research UK Clinical Trials Unit at the University of Birmingham, said: "This particular trial has yielded a dramatic difference in survival.
"It's incredibly rare to get such a significant increase by using existing drugs in a slightly different way."
The trial compared treatment using four rounds of Epirubicin followed by four rounds of standard chemotherapy (CMF) with six rounds of CMF alone.
In both groups the drug doses were higher than those often used routinely.
Over the trial recruitment period of five years, women who were treated with Epirubicin were 31% per cent less likely to relapse or die than women treated with CMF alone.
Many could benefit
The majority of the 40,000 new breast cancer cases diagnosed in the UK each year are treated with chemotherapy.
The researchers believe that survival could be improved for hundreds, if not thousands of these women.
The National Institute for Clinical Excellence (NICE) recommended in 2002 that chemotherapy for breast cancer should include Epirubicin or a similar drug - but until now there has been no definitive answer on how the drug might best be integrated into standard therapy.
Researcher Dr Helena Earl from the University of Cambridge said: "Chemotherapy is an important part of treatment for many women affected by breast cancer but there has been considerable debate and uncertainty as to the best drug regime.
"This trial provides clear evidence on which drugs to use, which order to give the drugs and how much to give."
Over 100 clinicians from 65 hospitals across the UK were involved in the study.
CMF is a combination of three drugs called Cyclophosphamide, Methotrexate and 5FU.
The results of the trial were announced at the American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.