Co-chairman of the EORTC 10994 trial. This is a prospective phase III clinical trial comparing anthracyclines with taxanes in breast cancer. It was the first pan-European phase III trial organised by EORTC in which collection of frozen biopsies was a condition for enrolment. The primary endpoint is a biological question: should p53 status dictate the choice of therapy? The trial closed recently after recruitment of the full 1840 patients. All samples are tested for p53 status using my yeast functional assay. About 200 samples have also been tested on Affymetrix microarrays.