Anastrozole Show Benefits Over Tamoxifen: “Five-year results from the Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial continue to suggest that anastrozole is superior to tamoxifen in the treatment of postmenopausal women with early-stage breast cancer.
Principal investigator Anthony Howell, MD, professor, department of medical oncology, Christie Hospital NHS Trust, and director, research and development, Institute of Health Sciences, Manchester, England, presented the data here on December 8th at the 27th San Antonio Breast Cancer Symposium.
The results of the ATAC trial’s main analysis were reported in full at the SABCS in 2001. That analysis showed that at a median follow-up of 33.3 months, 89.4% of women given anastrozole were disease-free, compared with 87.4% of women given tamoxifen. Based on that analysis, the US Food and Drug Administration approved anastrozole (Arimidex, AstraZeneca) for the adjuvant treatment of early breast cancer in postmenopausal women with hormone receptor-positive disease.
The updated analysis shows that the absolute difference in disease-free survival continues to increase over time, Dr. Howell said. At a median follow-up of 68 months, treatment with anastrozole led to a 13% increase in disease-free survival (P =.01), a 21% reduction in time to recurrence (P =.0005), and a 42% reduction in contralateral breast cancer “