A landmark clinical trial led by radiation oncologists in Australia, Canada and the United States has shown that radiation treatment of the lymph nodes in addition to the breast after breast cancer surgery can prolong the time women remain cancer-free.
For over ten years, the researchers monitored 1,832 women with breast cancer that had spread to the lymph nodes. A decade ater, 82 per cent of the women who received radiation to the breast and lymph nodes were free of cancer, compared to 77 per cent of women who received radiation to the breast only.
The clinical trial, which is being co-ordinated by the Trans Tasman Radiation Oncology Group (TROG Cancer Research) in Australia, published the findings on July 23 in the New England Journal of Medicine. Associate Professor Boon Chua, Director of Breast Service at the Peter MacCallum Cancer Centre and international Co-Chair of the trial — said the difference in cancer-free survival is statistically significant. "Breast cancer is the most common cancer in Australian women, and most women who have localised surgery to remove the cancer receive radiation to the breast after surgery. Women who have cancer detected in their lymph nodes may wish to discuss lymph node radiation with their doctors to help them make an informed decision about their treatment options."
Associate Professor Chua, who presented the findings at the Australia and New Zealand Breast Cancer Trials Group’s 37th Annual Scientific Meeting in Perth, noted the findings are important for many women with breast cancer. "This large international trial has shown that lymph node radiation not only reduced the likelihood of cancer coming back in the lymph nodes 10 years later, it also decreased the risk of cancer coming back in the other parts of the body, such as the liver and lungs, from 17.6 per cent to 13.7 per cent."
Chua also said lymph node radiation may cause side-effects such as lymphoedema of the arm, which need to be balanced against its benefits when women make their decision whether to have lymph node radiation. "Ultimately this is a personal decision that women would make with the support of their doctors."