Actualité - ASCO

Lymph Node Irradiation in Breast Cancer Confirmed Useful

Valérie Devillaine
Pr Poortmans presented the 15-year results of this vast european study at the ASCO meeting in Chicago.
Philip Poortmans

A vast 15-year European study has confirmed that lymph node irradiation serves a useful purpose in women with breast cancer affecting the axillary lymph nodes (under the armpit) or where the tumor is located on the medial side (near the lymph nodes of the sternum).
Prof. Philip Poortmans, Head of the Department of Radiotherapy and Oncology at Institut Curie,  and the principal investigator for the study, will present detailed results from the study. This will provide all oncologists with the evidence they need to make the best therapeutic choice for their patients.
Thirty years ago, all women affected by this type of cancer were offered radiotherapy of the lymph node areas to limit the risk of the disease spreading. However, at the end of the 1980s, a study revealed increased mortality in these patients due to the radiotherapy. In order to study this issue more closely, several doctors, including Prof. Poortmans, who was then based at Verbeeten Hospital in Tilburg, Netherlands, and Dr. Alain Fourquet, the former Head of the Department of Radiotherapy and Oncology at Institut Curie, launched a vast randomized trial. Between 1996 and 2004, 4004 patients were included in 43 centers across Europe. Half of these received lymph node irradiation, half did not. The first results, at 10 years’ follow-up, showed that there was a benefit to radiotherapy—limited, certainly, but significant. Prof. Poortmans will be presenting the 15-year follow-up results at the ASCO Meeting, which confirm the value of these treatments. With radiotherapy, overall patient mortality falls from 73.2 to 70.8%; mortality due to breast cancer and the risk of relapse also decrease.
A meta-analysis grouping the results from different studies involving over 14,000 patients is currently being drawn up by a team at Oxford, including Prof. Poortmans. This should refine the data and provide a better understanding of which patients should receive radiotherapy. It should be noted that over recent decades, the increasingly early diagnosis of breast cancer has reduced the rate of lymph node involvement from 40 to 25%, which means this controversial radiotherapy can be avoided in a large number of cases.