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Potential surrogate endpoints in cancer research – some considerations and examples


  • S. W. Duffy,

    1. Cancer Research UK Centre for EMS, Wolfson Institute of Preventive Medicine, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
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  • F. P. Treasure

    Corresponding author
    1. Department of Public Health and Primary Care, Eastern Cancer Registration and Information Centre, University of Cambridge, Cambridge, UK
    • Department of Public Health and Primary Care, Institute of Public Health, University Forvie Site, Robinson Way, Cambridge CB2 2SR, UK
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We present an introductory survey of the use of surrogates in cancer research, in particular in clinical trials. The concept of a surrogate endpoint is introduced and contrasted with that of a biomarker. It is emphasized that a surrogate endpoint is not universal for an indication but will depend on the mechanism of treatment. We discuss the measures of validity of a surrogate and give examples of both cancer surrogates and biomarkers on the path to surrogacy. Circumstances in which a surrogate endpoint may actually be preferred to the clinical endpoint are described. We provide pointers to the recent substantive literature on surrogates. Copyright © 2009 John Wiley & Sons, Ltd.