Tamoxifen for one year versus two years versus 6 months of Tamoxifen and 6 months of megestrol acetate: A randomized comparison in postmenopausal patients with high-risk breast cancer (DBCG 89C)

From January 1, 1990 to December 31, 1994, DBCG conducted a randomised trial in 1 615 postmenopausal women with operable, high-risk, receptor-positive or -unknown breast cancer. The patients were after surgery randomised to Tamoxifen for 1 year (TAM1), Tamoxifen for 2 years (TAM 2) or Tamoxifen for 6 months followed by megestrol acetate for 6 months (TAM/MA). When the preplanned sample size of 1 500 patients was reached it was decided to continue randomisation to TAM1 or TAM2 and the study was finally closed December 31, 1996. With a median follow-up of more than 10 years, there was no difference in disease-free survival (DFS) or overall survival (OS) among the three treatment arms. Similar results were obtained in the original and extended comparisons of Tamoxifen for 1 versus 2 years. A multivariate analysis in the perprotocol treated patients did not show significant differences in hazard ratios for DFS or OS among the three arms. Sideeffects were rare but more common in the TAM2 and TAM/MA arms Udgivelsesdato: 2008