ASCO Information "Wish I had Known"

Practice-changing cancer trial shows additional radiation decreases cancer recurrence

Jun 4, 2011 10:30:00 AM

TORONTO, June 4, 2011 /CNW/ - A Canadian-led clinical trial has found  that additional radiation treatment improves disease-free survival in  women with early breast cancer and reduces the risk of cancer  recurrence, a finding that could potentially change the standard  treatment for this group of patients. The trial was led by the NCIC Clinical Trials Group, which is funded by the Canadian Cancer Society.

The study enrolled more than 1,800 women who had been treated with  breast-conserving surgery (lumpectomy) and adjuvant chemotherapy or  endocrine therapy. In the trial, the women received either whole breast  radiation alone or whole breast radiation plus additional radiation to  the surrounding lymph nodes, called regional lymph node irradiation.

After a five-year follow-up, interim analysis of the data showed a  greater than 30 per cent improvement in disease-free survival for those  receiving additional radiation therapy. This included a 41 per cent  lower rate of cancer recurrence in the breast and lymph nodes and a 36  per cent lower rate of cancer recurrence in other parts of the body.

The results were presented today at the annual meeting of the American Society of Clinical Oncology.

"For women with node positive breast cancer who face a risk of  recurrence, these findings provide an important new treatment option,"  says Dr Christine Williams, Director of Research, Canadian Cancer Society. "We expect this research to change clinical practice so that  more women survive and thrive after cancer."

Current treatment for women with node-positive breast cancer has been  breast-conserving surgery plus removal of the lymph nodes, followed by  radiation to the breast. If a woman's cancer is considered high-risk,  such as a tumour larger than five cm or more than three positive  axillary (in the armpit) nodes, she often receives regional nodal  irradiation (RNI). Until now, however, the benefit of adding RNI for  women with one to three positive nodes has been unclear.

This trial is just one of three conducted by the NCIC CTG and funded by  the Canadian Cancer Society which this year has been selected as "Best  of ASCO". The other two studies include a landmark breast cancer  prevention trial and one which found a more effective way to treat  prostate cancer. Studies featured in Best of ASCO have the potential to  change clinical practice around the world.

Breast cancer is the most common cancer among Canadian women (excluding  non-melanoma skin cancer). In 2011, an estimated 23,400 women will be  diagnosed with breast cancer and 5,100 will die of it.

The NCIC Clinical Trials Group is a national research program of the  Canadian Cancer Society and receives programmatic funding, including  for this trial, from the Canadian Cancer Society Research Institute.  Additional support for the trial was provided by the US National Cancer Institute/Cancer Therapy Evaluation Program and the Canadian Breast Cancer Research Alliance.

The Canadian Cancer Society fights cancer by doing everything we can to  prevent cancer, save lives and support people living with cancer. Last  year, the Society funded more than $48 million in leading-edge research  projects across the country. When you want to know more about cancer,  visit our website at cancer.ca  or call our toll-free bilingual Cancer Information Service at 1-888  939-3333

Got my answer...

In the study of more than 1,800 women with breast conserving surgery, participants received whole breast radiation (WBI) alone or WBI plus radiation to the surrounding lymph nodes called regional lymph node irradiation (RNI). Most of the women had one to three positive lymph nodes while 10 per cent had high-risk, node-negative breast cancer. All had been treated with breast-conserving surgery and adjuvant chemotherapy or endocrine therapy.