Women can be given less radiotherapy and still beat breast cancer, landmark research reveals today.

Trials involving nearly 4500 patients, including breast cancer sufferers in Scotland, have shown fewer doses of the treatment can be just as effective at preventing tumours from coming back.

Specialists in Dundee are now researching whether one single bout of radiotherapy given at the same time as surgery to remove the growth can work equally as well as weeks of gruelling sessions.

The findings have been hailed as good news for women as it should mean they need fewer hospital visits.

Some UK cancer specialists have been recommending shorter courses of radiotherapy for some time, based on their experiences of the disease and the trial results, published today in journals the Lancet and Lancet Oncology, confirm their beliefs.

Breast cancer patients who do not have a full mastectomy receive radiotherapy after surgery to help prevent the cancer recurring. The international standard treatment regime involves 25 sessions, given five times a week for five weeks. During this period women receive a total radiation dose quantified as 50 Gray (Gy).

Half the women taking part in the UK trial, which began a decade ago, were treated along these lines. The remainder received radiotherapy in larger bouts but over a shorter time period and their total radiation exposure was lower overall. Some patients were given 40 Gy over three weeks.

The researchers monitored the patients for an average of five to six years and found that the rate of cancer coming back in the breast was very low in both groups. Similarly, the rate of side-effects were low, and no higher among those given the newer treatment regime.

Lead researcher Professor John Yarnold, from the Institute of Cancer Research and the Royal Marsden Hospital, said: "These trials represent a successful 10-year collaboration between cancer specialists and several thousand women motivated to help others by volunteering for research.

"The results suggest that a high total dose given in 25 small treatments is no better than simpler schedules using fewer exposures to a lower total dose.

"Shorter therapies giving fewer, larger treatments are obviously convenient for patients."

Ninewells Hospital in Dundee took part in the research and is now one of 16 centres worldwide offering breast cancer patients a single, large dose of radiation, during surgery as part of another trial.

So far, 150 patients have participated in this ground-breaking research with half undergoing traditional treatment. Dr Jayant Vaidya, breast cancer surgeon at the hospital, said the findings so far were encouraging.

He said: "It makes such a difference to people who are 70 years old to come in and have their operation and radiotherapy in one go."

Cancer Research UK, the Medical Research Council and the Department of Health funded the 4500-patient trial, which involved 35 hospitals.

Dr Lesley Walker, director of information for Cancer Research UK, said: "It is important for patients that we continue research like this to fine-tune current treatment."