Maastricht Delphi consensus on event definitions for classification of recurrence in breast cancer research.
BACKGROUND
In breast cancer studies, many different endpoints are used. Definitions are often not provided or vary between studies. For instance, "local recurrence" may include different components in similar studies. This limits transparency and comparability of results. This project aimed to reach consensus on the definitions of local event, second primary breast cancer, regional and distant event for breast cancer studies.


METHODS
The RAND-UCLA Appropriateness method (modified Delphi method) was used. A Consensus Group of international breast cancer experts was formed, including representatives of all involved clinical disciplines. Consensus was reached in two rounds of online questionnaires and one meeting.


RESULTS
Twenty-four international breast cancer experts participated. Consensus was reached on 134 items in four categories. Local event is defined as any epithelial breast cancer or ductal carcinoma in situ (DCIS) in the ipsilateral breast, or skin and subcutaneous tissue on the ipsilateral thoracic wall. Second primary breast cancer is defined as epithelial breast cancer in the contralateral breast. Regional events are breast cancer in ipsilateral lymph nodes. A distant event is breast cancer in any other location. Therefore, this includes metastasis in contralateral lymph nodes and breast cancer involving the sternal bone. If feasible, tissue sampling of a first, solitary, lesion suspected for metastasis is highly recommended.


CONCLUSIONS
This project resulted in consensus-based event definitions for classification of recurrence in breast cancer research. Future breast cancer research projects should adopt these definitions to increase transparency. This should facilitate comparison of results and conducting reviews as well as meta-analysis.
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Martine
M
Moossdorff
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Lori M
LM
van Roozendaal
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Luc J A
LJ
Strobbe
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Stefan
S
Aebi
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
David A
DA
Cameron
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
J Michael
JM
Dixon
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Armando E
AE
Giuliano
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Bruce G
BG
Haffty
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Brigid E
BE
Hickey
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Clifford A
CA
Hudis
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
V Suzanne
VS
Klimberg
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Bogda
B
Koczwara
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Thorsten
T
Kühn
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Marc E
ME
Lippman
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Anthony
A
Lucci
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Martine
M
Piccart
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Benjamin D
BD
Smith
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Vivianne C G
VC
Tjan-Heijnen
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Cornelis J H
CJ
van de Velde
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Kimberly J
KJ
Van Zee
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Jan B
JB
Vermorken
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Giuseppe
G
Viale
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Adri C
AC
Voogd
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Irene L
IL
Wapnir
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Julia R
JR
White
Department of Surgery and GROW School for Oncology and Developmental Biology (MM, MLS), Department of Surgery and Radiology (LMvR), Department of Medical Oncology, GROW School for Oncology and Developmental Biology (VCGTH), and Department of Epidemiology and GROW School for Oncology and Developmental Biology (ACV), Maastricht University Medical Center, Maastricht, the Netherlands; Department of Surgery, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands (LJAS); Division of Medical Oncology, Luzerner Kantonsspital, Lucerne, Switzerland (SA); Edinburgh Cancer Research Centre, University of Edinburgh and NHS Lothian (DAC), Edinburgh Breast Unit (JMD), Western General Hospital, Edinburgh, UK; Cedars-Sinai Medical Center, Los Angeles, CA (AEG); Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (BGH); Mater Centre Radiation Oncology Service, Princess Alexandra Hospital, Brisbane, Australia (BEH); Breast Cancer Medicine Service, Memorial Sloan Kettering Cancer Center and Professor of Medicine, Weill Cornell Medical College, New York, NY (CAH); University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, Little Rock, AR (VSK); Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, Australia (BK); Interdisciplinary Breast Centre, Department of Gynaecology and Obstetrics, Klinikum Esslingen, Germany (TK); University of Miami Miller School of Medicine, Miami, FL (MEL); Radiation Oncology (BDS) and Department of Surgical Oncology, Division of Surgery (AL), University of Texas/MD Anderson Cancer Center, Houston, TX; Institut Jules Bordet, Université Libre de Bruxelles, Head of Medicine Department, Brussels, Belgium (MP); Surgery, University Medical Center, Leiden, the Netherlands (CJHvdV); Breast Service, Memorial Sloan-Kettering Cancer Center, Evelyn Lauder Breast Center, New York, NY(KJVZ); Antwerp University Hospital, Department of Medical Oncology, Edegem, Belgium (JBV); Department of Pathology, European Institute of 
Marjolein L
ML
Smidt
D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000175:diagnosis; D003697:Delphi Technique; D005260:Female; D006801:Humans; D007391:International Cooperation; D008207:Lymphatic Metastasis; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000473:pathology; D016609:Neoplasms, Second Primary / Q000175:diagnosis* / Q000473:pathology; D012878:Skin Neoplasms / Q000556:secondary; D011795:Surveys and Questionnaires; D035441:Thoracic Wall / Q000473:pathology