109779-132

Radiotherapy or surgery of the axilla after a positive sentinel node in breast cancer patients: Final analysis of the EORTC AMAROS trial (10981/22023).

Subcategory: 
Category: 
Breast Cancer - Triple-Negative/Cytotoxics/Local Therapy
Session Type and Session Title: 
Oral Abstract Session, Breast Cancer - Triple-Negative/Cytotoxics/Local Therapy
Abstract Number: 

LBA1001

Citation: 

J Clin Oncol 31, 2013 (suppl; abstr LBA1001)

Author(s): 

Emiel J. Rutgers, Mila Donker, Marieke Evelien Straver, Philip Meijnen, Cornelis J. H. Van De Velde, Robert E. Mansel, Helen Westenberg, Lorenzo Orzalesi, Willem H. Bouma, Huub van der Mijle, Grard A. P. Nieuwenhuijzen, Sanne C. Veltkamp, Leen Slaets, Carlo G. M. Messina, Nicole J. Duez, Coen Hurkmans, Jan Bogaerts, Geertjan van Tienhoven; Netherlands Cancer Institute, Amsterdam, Netherlands; NKI-AVL, Amsterdam, Netherlands; Leiden University Medical Center, Department of Surgery, Leiden, Netherlands; Cardiff University, Cardiff, United Kingdom; Institute for Radiation Oncology Arnhem, Arnhem, Netherlands; Breast Unit, Careggi University Hospital, Florence, Italy; Department of Surgery, Gelre Hospital, Apeldoorn, Netherlands; Department of Surgery, Nij Smellinghe Hospital, Drachten, Netherlands; Department of Surgery, Catharina Hospital, Eindhoven, Netherlands; Department of Surgery, Amstelland Hospital, Amstelveen, Netherlands; European Organisation for Research and Treatment of Cancer, Brussels, Belgium; EORTC Headquarters, Brussels, Belgium; Department of Radiation Oncology, Catherina Hospital, Eindhoven, Netherlands; Department of Radiation Oncology, Academic Medical Centre, Amsterdam, Netherlands


Abstracts that were granted an exception in accordance with ASCO's Conflict of Interest Policy are designated with a caret symbol (^).

Abstract Disclosures

Abstract: 

Background: Sentinel node biopsy (SNB) is standard in assessing axillary lymph node status for cN0 breast cancer patients. In case of a positive SNB, if treatment is advised, axillary lymph node dissection (ALND) is the current standard. Although ALND provides excellent regional control, it may give harmful side effects. Axillary radiotherapy (ART) instead of ALND was hypothesized to provide comparable regional control and less side effects. Methods: From 2001 to 2010, patients with cT1E2N0 primary breast cancer were enrolled in the EORTC phase III non-inferiority AMAROS trial. Patients were randomized between ALND and ART in case of a positive SNB. Primary endpoint was 5-year axillary recurrence rate. Secondary endpoints were overall survival (OS), disease-free survival (DFS), quality of life (QOL), shoulder movement and lymphedema at 1 and 5 years. Results: Of the 4,806 patients entered in the trial, 744 in the ALND-arm and 681 in the ART-arm had a positive SNB, 60% with a macrometastasis. The two treatment-arms were comparable regarding age, tumor size, grade, tumor type, and adjuvant systemic treatment. With a median follow up of 6.1 years, the 5-year axillary recurrence rate after a positive SNB was 0.54% (4/744) after ALND versus 1.03% (7/681) after ART. The planned non-inferiority test was underpowered because of the unexpectedly low number of events. The axillary recurrence rate after a negative SNB was 0.8% (25/3131). There were no significant differences between treatment arms regarding OS (5 yr estimates: 93.27% ALND, 92.52% ART, p=0.3386) and DFS (5 yr estimates: 86.90% ALND, 82.65% ART, p=0.1788). Lymphedema was found significantly more often after ALND (1yr: 40% ALND, 22% ART, p<0.0001 and 5yr: 28% ALND, 14% ART, p<0.0001). There was a nonsignificant trend toward more early shoulder movement impairment after ART. These findings were compatible with a trend in two QOL items in the arm symptom scale: swelling (ART better) and movement (ALND better). There were no other differences in QOL. Conclusion: ALND and ART after a positive SNB provide excellent and comparable regional control. ART reduces the risk of short-term and long-term lymphedema compared to ALND. Clinical trial information: NCT00014612.