Description
Patients diagnosed with breast cancer were recruited to an important trial, the Tamoxifen Window Trial, in two series, series A during 1988-1989 and series B during 1989-1990. Some patients received tamoxifen for short windows. Clinical samples (biopsies) for this trial were collected before and after treatment. These biopsies were available as formalin-fixed paraffin-embedded (FFPE) tissue blocks.