Radiotherapy improves 15-year survival after breast-conserving surgery (lumpectomy)

December 15, 2005

After lumpectomy for breast cancer, radiotherapy to the remaining breast tissue can improve the chances of long-term survival, according to a study published in this week's issue of The Lancet. This is one of the main new findings from a worldwide overview of detailed data from 40 000 women with early breast cancer in randomised trials of radiotherapy, and of different types of surgery carried out by the Early Breast Cancer Trialists' Collaborative Group (EBCTCG).

Breast-conserving surgery removes just the cancer and a little of the normal tissue around it, leaving behind as much healthy tissue as possible. A few cancer cells may, however, also be left behind. Doctors already knew that giving patients breast radiotherapy soon after they recover from surgery reduce the chances of local recurrence. The new study shows that the chances of dying from breast cancer are also reduced by breast radiotherapy soon after surgery. On average, for every four local recurrences avoided by radiotherapy, about one breast cancer death is avoided. The main effect of radiotherapy on local recurrence is seen during the first few years after treatment, but the main effect on mortality is seen in later years. The effects of radiotherapy add to the known improvements in long-term survival produced by chemotherapy and hormone therapy (see EBCTCG, Lancet 2005; 365:1687).

Although guidelines in America and Europe already recommend radiotherapy after breast-conserving surgery they are not always followed. This is partly because of the side-effects of radiotherapy, and partly because recurrence in a conserved breast can usually be removed by further surgery, but it may also be because there was no definite evidence on survival.

Professor Sarah Darby, who helped co-ordinate the collaboration, states: "We already knew that radiotherapy to a conserved breast substantially reduces the chances of local recurrence of breast cancer, and now we know that it also reduces the long-term chances of dying from the disease." After breast-conserving surgery the 5-year risks of local recurrence were 7% with radiotherapy versus 26% without (a reduction of 19%), while the 15-year breast cancer mortality was 30.5% with radiotherapy versus 35.9% without (a reduction of 5.4%). These reductions are highly statistically significant.

Another main finding concerns the lymph nodes in the armpit. Instead of breast-conserving surgery, the entire breast may be removed surgically (mastectomy). If breast cancer has already spread to the lymph nodes in the armpit then radiotherapy can again produce a substantial reduction in the chances of local recurrence and improve the chances of long-term survival, and, again, for every four local recurrences avoided by radiotherapy, about one breast cancer death is avoided. In women whose breast cancer had already spread to the nodes in the armpit, the 5-year risks of local recurrence, after mastectomy and surgery to the armpit, were 6% with radiotherapy versus 23% without (a reduction of 17%), while the 15-year breast cancer mortality was 54.7% with radiotherapy versus 60.1% without (again a reduction of 5.4%).

Dr Paul McGale, another study co-ordinator, states: "In Europe and North America many women whose breast cancer has spread to several nodes in the armpit do not get radiotherapy, partly because of the side-effects, even though it reduces the risk of dying from the disease."

If the entire breast has been removed and there is no spread to the nearby lymph nodes, then the risk of local recurrence is so small that there is little need for radiotherapy and it is generally not given, because of its side-effects. Dr Carolyn Taylor, a clinical oncologist who worked on the study, states: "The present study shows that radiotherapy occasionally caused life-threatening diseases such as heart attack, or a new cancer in the lung or opposite breast. But, radiotherapy techniques have improved considerably in recent years, and the heart and lungs receive less radiation than in the past."

Study co-ordinator Professor Sir Richard Peto comments: "These results may also be relevant to some previous patients who did not get radiotherapy. Most local recurrences are seen in the first two or three years, so there would probably be little point in offering radiotherapy to women who have been free of cancer for the past few years. But, it might be worth considering radiotherapy for some women who, within just the last year or two, have had lumpectomy for breast cancer or mastectomy for cancer that had spread to the armpit, and who didn't get radiotherapy after surgery because of the side-effects."
-end-
Contact: Sarah Darby, Paul McGale, Carolyn Taylor or Richard Peto at the Clinical Trial Service Unit (CTSU), Richard Doll Building, Old Road Campus, University of Oxford, Oxford OX3 7LF. Sarah Darby T): +44 (0) 1865 743864/ +44 (0) 7851 397920 (mobile) sarah.darby@ctsu.ox.ac.uk Richard Peto T): +44 (0) 1865 743801/ +44 (0) 7771 960329 (mobile) secretary@ctsu.ox.ac.uk

Cancer Research UK press office sophy.gould@cancer.org.uk T) 0207 061 8318 (07050 264 059 out-of-hours)

University of Oxford press office T) 01865 280 528 press.office@admin.ox.uk

Medical Research Council press office T) 0207 670 5139 Laura.Thomas@headoffice.mrc.ac.uk

Note to editors:

A PDF of the full report is available from The Lancet press office pressoffice@lancet.com and the text, figures and tables are available on the CTSU website (www.ctsu.ox.ac.uk/projects/ebctcg)

Lancet

Related Breast Cancer Articles from Brightsurf:

Oncotarget: IGF2 expression in breast cancer tumors and in breast cancer cells
The Oncotarget authors propose that methylation of DVDMR represents a novel epigenetic biomarker that determines the levels of IGF2 protein expression in breast cancer.

Breast cancer: AI predicts which pre-malignant breast lesions will progress to advanced cancer
New research at Case Western Reserve University in Cleveland, Ohio, could help better determine which patients diagnosed with the pre-malignant breast cancer commonly as stage 0 are likely to progress to invasive breast cancer and therefore might benefit from additional therapy over and above surgery alone.

Partial breast irradiation effective treatment option for low-risk breast cancer
Partial breast irradiation produces similar long-term survival rates and risk for recurrence compared with whole breast irradiation for many women with low-risk, early stage breast cancer, according to new clinical data from a national clinical trial involving researchers from The Ohio State University Comprehensive Cancer Center - Arthur G.

Breast screening linked to 60 per cent lower risk of breast cancer death in first 10 years
Women who take part in breast screening have a significantly greater benefit from treatments than those who are not screened, according to a study of more than 50,000 women.

More clues revealed in link between normal breast changes and invasive breast cancer
A research team, led by investigators from Georgetown Lombardi Comprehensive Cancer Center, details how a natural and dramatic process -- changes in mammary glands to accommodate breastfeeding -- uses a molecular process believed to contribute to survival of pre-malignant breast cells.

Breast tissue tumor suppressor PTEN: A potential Achilles heel for breast cancer cells
A highly collaborative team of researchers at the Medical University of South Carolina and Ohio State University report in Nature Communications that they have identified a novel pathway for connective tissue PTEN in breast cancer cell response to radiotherapy.

Computers equal radiologists in assessing breast density and associated breast cancer risk
Automated breast-density evaluation was just as accurate in predicting women's risk of breast cancer, found and not found by mammography, as subjective evaluation done by radiologists, in a study led by researchers at UC San Francisco and Mayo Clinic.

Blood test can effectively rule out breast cancer, regardless of breast density
A new study published in PLOS ONE demonstrates that Videssa® Breast, a multi-protein biomarker blood test for breast cancer, is unaffected by breast density and can reliably rule out breast cancer in women with both dense and non-dense breast tissue.

Study shows influence of surgeons on likelihood of removal of healthy breast after breast cancer dia
Attending surgeons can have a strong influence on whether a patient undergoes contralateral prophylactic mastectomy after a diagnosis of breast cancer, according to a study published by JAMA Surgery.

Young breast cancer patients undergoing breast conserving surgery see improved prognosis
A new analysis indicates that breast cancer prognoses have improved over time in young women treated with breast conserving surgery.

Read More: Breast Cancer News and Breast Cancer Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.