Long-term effects on the incidence of second primary cancers in a randomized trial of two and five years of adjuvant tamoxifen
Background: Tamoxifen is a well established treatment for breast cancer, but its long-term effects on the incidence of secondary cancers are not fully evaluated. Material and methods: We have studied 4128 postmenopausal patients with early stage breast cancer who were alive and free of breast cancer recurrence after two years of tamoxifen, and who were randomized to receive totally two or five yea