%0 Journal Article
%T Surrogates are just surrogates, but helpful just the same
%A Carol Fabian
%J Breast Cancer Research
%D 2007
%I BioMed Central
%R 10.1186/bcr1816
%X To be credible, an SEB must have biological plausibility and a strong association with ultimate outcome. To be used for prevention, an SEB should be identified as being causally related to the development of precancer and cancer. Modulation of the SEB through an intervention should predict outcome. The SEB should be reproducible and reliable. Reproducibility is generally maximized with a quantitative biomarker. Optimally, both risk and response SEBs should be prospectively validated in a clinical trial in which the nonsurrogate outcome is also being evaluated [1,2].SEBs are used in clinical trials to identify effective new strategies faster and more economically with fewer patients. They may also offer insight into why or why not a particular therapy does not work. In the patient care setting, SEBs are used to determine whether and when to change the therapeutic plan.In the metastatic setting, typically the same surrogate markers are measured repeatedly to assess response or progression often by imaging and/or physical examination. Two surrogate markers can independently predict the same outcome, but results at any single point in time may be discordant. Consequently, it is important to understand the biology that underlies the surrogate in order to avoid making inappropriate clinical decisions.In the neoadjuvant setting, a low Ki-67 a few weeks after initiation of treatment and pathological response after several months of treatment both predict long-term disease-free survival [3-5]. Both biomarkers are currently used in the research setting, and pathological stage after neoadjuvant treatment is used clinically to estimate distant disease-free survival. It is probable that, in the near future, early reduction in breast proliferation will be used along with clinical indices to determine whether to switch antihormonal or chemotherapeutic treatment during the neoadjuvant period. Pathological response after neoadjuvant chemotherapy will also probably be used to determi
%U http://breast-cancer-research.com/content/9/S2/S18