Arimidex: Compliance and Arthralgias in Clinical Therapy (COMPACT)

Patients are eligible for inclusion in this NIS if they have taken anastrozole either upfront or following two to three years of tamoxifen treatment ("switch") for at least three and not more than six months prior to offering an individual participation in this program. Treatment should follow local therapy guidelines and standard practice. Treatment decisions for patients participating in this study including assessments or supportive therapy during follow-up visits will also follow guidelines and remain independent of the program.