Ten-Year Survival Results of a Randomized Trial of Irradiation of Internal Mammary Nodes After Mastectomy

Journal Article · Thu Aug 01 04:00:00 EDT 2013 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2013.03.021· OSTI ID:22267828

Hennequin, Christophe ^[1]; Bossard, Nadine ^[2]; Servagi-Vernat, Stéphanie ^[3]; Maingon, Philippe ^[4]; Dubois, Jean-Bernard ^[5]; Datchary, Jean ^[6]; Carrie, Christian ^[7]; Roullet, Bernard ^[8]; Suchaud, Jean-Philippe ^[9]; Teissier, Eric ^[10]; Lucardi, Audrey ^[11]; Gerard, Jean-Pierre ^[12]; Belot, Aurélien ^[2]; others, and

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1. Hôpital Saint-Louis, AP-HP et Université de Paris VII (France)
2. Hospices Civils de Lyon, Service de Biostatistique, Université Lyon 1, Lyon, and CNRS, UMR5558, Laboratoire de Biométrie et Biologie Evolutive, Equipe Biotatistique-Santé, Villeurbanne (France)
3. Centre hospitalier Universitaire de Besançon (France)
4. Centre François Leclerc, Dijon (France)
5. Centre Val d'Aurelle, Montpellier (France)
6. Centre Hospitalier d'Annecy (France)
7. Centre Léon Bérard, Lyon (France)
8. Centre Hospitalier Universitaire de Limoges (France)
9. Centre Hospitalier de Roanne (France)
10. Centre de Radiothérapie de Mougins (France)
11. Hospices Civils de Lyon (France)
12. Centre Antoine Lacassagne, Nice (France)

Purpose: To evaluate the efficacy of irradiation of internal mammary nodes (IMN) on 10-year overall survival in breast cancer patients after mastectomy. Methods and Patients: This multicenter phase 3 study enrolled patients with positive axillary nodes (pN+) or central/medial tumors with or without pN+. Other inclusion criteria were age <75 and a Karnofsky index ≥70. All patients received postoperative irradiation of the chest wall and supraclavicular nodes and were randomly assigned to receive IMN irradiation or not. Randomization was stratified by tumor location (medial/central or lateral), axillary lymph node status, and adjuvant therapy (chemotherapy vs no chemotherapy). The prescribed dose of irradiation to the target volumes was 50 Gy or equivalent. The first 5 intercostal spaces were included in the IMN target volume, and two-thirds of the dose (31.5 Gy) was given by electrons. The primary outcome was overall survival at 10 years. Disease-free survival and toxicity were secondary outcomes. Results: T total of 1334 patients were analyzed after a median follow-up of 11.3 years among the survivors. No benefit of IMN irradiation on the overall survival could be demonstrated: the 10-year overall survival was 59.3% in the IMN-nonirradiated group versus 62.6% in the IMN-irradiated group (P=.8). According to stratification factors, we defined 6 subgroups (medial/central or lateral tumor, pN0 [only for medial/central] or pN+, and chemotherapy or not). In all these subgroups, IMN irradiation did not significantly improve overall survival. Conclusions: In patients treated with 2-dimensional techniques, we failed to demonstrate a survival benefit for IMN irradiation. This study cannot rule out a moderate benefit, especially with more modern, conformal techniques applied to a higher risk population.

• OSTI ID: 22267828
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 5 Vol. 86; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
CHEMOTHERAPY
CHEST
DOSES
HEALTH HAZARDS
IRRADIATION
LYMPH NODES
MAMMARY GLANDS
NEOPLASMS
PATIENTS
RADIOTHERAPY
TOXICITY