There are two approaches when targeting cancer with radiotherapy. One takes in the whole region, the other targets the original tumor site.  Both have shown to have their advantages and disadvantages, but new research out of the UK indicates that tumor site-specific radiotherapy may offer considerably more benefits for breast cancer patients.

The scientists drew their data from 30 radiotherapy centers across the UK, led by The Institute of Cancer Research in London and the Cancer Research UK Cambridge Center. In all, more than 2,000 women aged 50 or over who had early stage breast cancer that was at a low risk of coming back were studied.

Following breast conserving surgery, some patients were treated with whole breast radiotherapy while others received partial breast radiotherapy. Targeting the whole breast has been the clinical standard when treating this type of cancer. But those women whose radiotherapy targeted just the site of the tumor's origination reported fewer long term changes to the appearance and feel of their breast than did those who had radiotherapy to the whole breast.

Dr. Charlotte Coles, Reader in Breast Radiation Oncology at Cambridge University, chief investigator for the trial and first author of the publication, said: “We started this trial because there was evidence that if someone’s cancer returns, it tends to do so close to the site of the original tumor, suggesting that some women receive unnecessary radiation to the whole breast.

“Now we have evidence to support the use of less, but equally effective, radiotherapy for selected patients.”

Professor Judith Bliss, scientific lead for the study within the Clinical Trials and Statistics Unit at The Institute of Cancer Research, London, said: “We’re delighted that the results of this trial have the potential to lead to a real change in the way selected breast cancer patients are treated.

“The technique used here can be carried out on standard radiotherapy machines so we anticipate that these results will lead to further uptake of this treatment at centers across the country and worldwide.”

Professor Arnie Purushotham, Cancer Research UK’s senior clinical adviser, said: “One of the challenges when treating early stage breast cancer is trying to minimize the side effects that can have a real impact on a woman’s life, without affecting the chances of curing her.

“This approach could spare many women significant physical discomfort and emotional distress.” 

The research has been published in The Lancet.