Breast Cancer Res Treat (2012) 132:675–682 DOI 10.1007/s10549-011-1892-5 E P I D E M I O L O G Y Surgical treatment of early stage breast cancer in elderly: an international comparison M. Kiderlen • E. Bastiaannet • P. M. Walsh • N. L. Keating • S. Schrodi • J. Engel • W. van de Water • S. M. Ess • L. van Eycken • A. Miranda • L. de Munck • C. J. H. van de Velde • A. J. M. de Craen • G. J. Liefers Received: 16 November 2011 / Accepted: 18 November 2011 / Published online: 27 November 2011 The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Over 40% of breast cancer patients are diag- nosed above the age of 65. Treatment of these elderly patients will probably vary over countries. The aim of this study was to make an international comparison (several European countries and the US) of surgical and radiation treatment for elderly women with early stage breast cancer. Survival comparisons were also made. Data were obtained from national or regional population-based registries in the Netherlands, Switzerland, Ireland, Belgium, Germany, and Portugal. For the US patients were selected from the Sur- veillance, Epidemiology, and End Results (SEER) data- base. Early stage breast cancer patients aged C65 diagnosed between 1995 and 2005 were included. An international comparison was made for breast and axillary surgery, radiotherapy after breast conserving surgery (BCS), and relative or cause-speciﬁc survival. Overall, 204.885 patients were included. The proportion of patients not receiving any surgery increased with age in many countries; however, differences between countries were large. In most countries more than half of all elderly patients received breast conserving surgery (BCS), with the highest percentage in Switzerland. The proportion of elderly patients that received radiotherapy after BCS decreased with age in all countries. Moreover, in all countries the proportion of patients who do not receive axillary surgery increased with age. No large differences in survival between countries were recorded. International comparisons of surgical treatment for elderly women with early stage breast cancer are scarce. This study showed large international differences in treatment of elderly early stage breast cancer patients, with the most striking result the large proportion of elderly who did not undergo surgery M. Kiderlen E. Bastiaannet W. van de Water C. J. H. van de Velde G. J. Liefers (&) Department of Surgery, Leiden University Medical Center, P.O. Box 9600, 2300, RC, Leiden, The Netherlands e-mail: g.j.liefers@lumc.nl E. Bastiaannet W. van de Water A. J. M. de Craen Gerontology & Geriatrics, Leiden University Medical Center, Leiden, The Netherlands P. M. Walsh National Cancer Registry, Cork, Ireland N. L. Keating Brigham and Women’s Hospital and Harvard Medical School, Boston, USA S. Schrodi J. Engel Munich Cancer Registry (MCR) of the Munich Cancer Center (MCC), Clinic Großhadern/IBE Ludwig-Maximilians- University, Munich, Germany S. M. Ess Cancer Registry of St. Gallen, Appenzell, Switzerland L. van Eycken National Cancer Registry of Belgium, Brussels, Belgium A. Miranda Cancer Registry of Southern Portugal (ROR-Sul), Lisboa, Portugal L. de Munck Comprehensive Cancer Centre the Netherlands, Utrecht, The Netherlands 123