Application status of tamoxifen in endocrine therapy for early breast cancer

Abstract

The aim of the present study was to investigate the application status of tamoxifen as an adjuvant treatment for early-stage breast cancer. Data for patients with early breast cancer were collected from an information management system for breast cancer in a single hospital between 1989 and 2012. The inclusion criteria included no distant metastasis during diagnosis with breast cancer, and a diagnosis of estrogen and/or progesterone receptor-positive breast cancer, or an unclear hormonal receptor status with tamoxifen used as the preferred drug. A total of 2,738 patients were selected, with 99.4% female and 0.6% male patients. Within females, 75.7% were premenopausal when diagnosed with early breast cancer, 24.3% were postmenopausal, and the median age of menopause was 47 years. The percentage of tamoxifen preference in adjuvant therapy was 97.3% prior to 2000, which decreased to 60.4% in 2011. Tamoxifen preference among premenopausal patients reduced from 97.3% prior to 2000 to 89.5% in 2011, while in postmenopausal patients tamoxifen preference declined from 97.4% prior to 2000 to 22.7% in 2011. One-year duration of tamoxifen treatment accounted for 79.4% of cases, while five-year duration accounted for 24.7%. The rate of one-year disease-free survival (DFS) was 98.5% and of five-year DFS was 89.1%. Patients with early breast cancer had a one-year overall survival (OS) rate of 99.2% and a five-year OS rate of 95.6%. The gradually decreased usage and shortened duration of tamixofen treatment, as well as reduced DFS and OS rates were observed in a ‘real world’ clinical setting. Improved treatment compliance in patients is recommended.