Overview ATAC - Endometrial Sub-Protocol Status: Completed Trial end date: 2005-12-01 Target enrollment: Participant gender: Summary To compare the difference between the ARIMIDEX group and the tamoxifen group in the incidence of abnormal endometrial histological findings arising after treatment has commenced. Phase: Phase 3 Details Lead Sponsor: AstraZenecaTreatments: AnastrozoleTamoxifen