Randomized trial of adjuvant tamoxifen in node negative postmenopausal breast cancer. Stockholm Breast Cancer Study Group.

The paper presents long-term results of a randomized trial of adjuvant tamoxifen (40 mg daily for 2 or 5 years) versus surgery alone including 1,347 postmenopausal patients with histologically negative axillary nodes and a tumour diameter less than or equal to 30 mm. Data on the estrogen receptor status of the primary tumour were available in 1,136 patients (84%). At a median follow-up of 7 years (range 1.7-13.0 years) there was a significant prolongation of the recurrence-free survival among those allocated to tamoxifen (p less than 0.01), significantly fewer deaths due to breast cancer (p = 0.02) and a trend towards improved overall survival (p = 0.11). The treatment benefit was restricted to patients with ER-positive tumours. There was no significant reduction of breast cancer recurrences in the tamoxifen group among patients whose tumours were classified as ER-negative. The results support and extend previous studies in showing a long-term benefit of tamoxifen in postmenopausal breast cancer patients with node-negative, estrogen receptor positive disease.