High levels of uPA and PAI-1 predict a good response to anthracyclines

Excerpt

First, they outline clearly the difference between prognostic and predictive factors, prognostic factors being biomarkers that are related to outcome, not necessarily in relation to particular treatments, while predictive biomarkers are related to outcome in relation to the use of particular therapies [1] (see Fig. 1). The ideal study design in which to explore predictive factors is one in which patients are randomly allocated to receive the therapy in question (in this case anthracycline containing chemotherapy) versus a control therapy (in this case non-anthracycline containing chemotherapy). While prognostic factors can be studied in cohorts or randomized trials, the gold standard scenario for the study of predictive factors is that of studies in which patients are randomized to receive the treatment of interest or not. It is important, in this context, to stress that a retrospective analyses testing retrospectively measured biomarkers in a prospectively randomized trial still preserve the lack of bias of the original randomized design, unless there is systematic (related to treatment) bias in the availability of specimens.

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