Safety and Efficacy Study of Femara(Letrozole) as an Extended Adjuvant Treatment in Breast Cancer Patients

Title of study: An observational, multicenter study on the safety and efficacy of Femara® (Letrozole) as an extended adjuvant treatment in breast cancer patients who completed adjuvant Tamoxifen or Toremifen treatment Objectives: The major objective of the study is to assess safety and efficacy of Femara® in women who had undergone resection of a primary breast cancer and subsequently received prior adjuvant tamoxifen or toremifen therapy for 5 years in real-life condition. The study aims at the following objectives: 1. To identify unknown adverse reactions, especially serious adverse reactions 2. To evaluate incidence and descriptions of adverse reactions under the routine drug use 3. To identify factors that may affect the safety of Femara® 4. To identify factors that may affect the efficacy of Femara® Methodology: This will be an open-label, multi-center, single-arm, observational phase IV study. Number of centers \& patients: Approximately 610 (planned No. of patients for total study period) patients from 4 centers will be enrolled in this study. Population: Postmenopausal early breast cancer patients who have finished adjuvant treatment with Tamoxifen or Toremifen for 5 years after curative surgery as "indications" described in local product labeling. Investigational drug: Femara® will be administered orally as described in "dose \& administration" of local product labeling up to 3 years. Study duration: FPFV May. 2006, LPFV Dec. 2011. Study drug will be administered for up to 3 years with renewal of contract on yearly basis.