PGR and neoplasm: In patients with tumours expressing both the oestrogen and progesterone receptor, a statistically significant benefit of 6.4% favouring 6 years of anastrozole was observed, with a 10-year adapted disease-free survival of 70.8% (95% CI 67.0–74.3) in the 6-year treatment group versus 64.4% (95% CI 60.4–68.1) in the 3-year treatment group (HR 0.77; 95% CI 0.63–0.93) (Figs. 3 and 4A, Supplementary Table S2).