An April 3 News story ("Upstaging Tamoxifen? New Classes ofDrugs Emerging for Breast Cancer", p. 474) incorrectly summarizedthe results of the Arimidex and Tamoxifen Alone or in Combination(ATAC) clinical trial. The trial found that, compared with tamoxifenalone, the aromatase inhibitor anastrozole statistically significantlyreduced the relative risk of disease recurrence in postmenopausalwomen with early-stage breast cancer. The combination of anastrozoleand tamoxifen was not statistically significantly differentfrom tamoxifen alone. The Journal regrets the error.