Breast cancer trial stopped earlyBMJ 1998; 316 doi: https://doi.org/10.1136/bmj.316.7139.1185d (Published 18 April 1998) Cite this as: BMJ 1998;316:1185
- Deborah Josefson
- San Francisco
American investigators have halted the breast cancer prevention trial 14 months earlier than expected after they found a 45% reduction in the incidence of breast cancer among women who took tamoxifen, compared with those who took a placebo.
The double blind trial included 13388 healthy women at high risk of developing breast cancer. In the group randomised to take 20 mg a day of tamoxifen there were 85 cases of invasive breast cancer, compared with 154 cases in the women assigned to the placebo group. The women were followed on average for four years. The results have yet to be published in any journal.
An independent safety monitoring committee, after reviewing the data at its regularly scheduled meeting on 24 March, recommended that the trial should be unblinded and the women in the placebo group given the opportunity to switch to tamoxifen. The women will continue to be monitored by the investigators.