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Patients with estrogen receptor (ER)+/progesterone receptor (PR)− and/or HER-2 overexpressing breast carcinomas may derive lower benefit from endocrine treatment. We examined retrospectively data from 972 breast cancer patients who received tamoxifen (725), tamoxifen + Gn-RH analogs (127) and aromatase inhibitors (120) as adjuvant treatments. ER+/PR− versus ER+/PR+ tumours were characterised by larger size (P=0.001), higher tumour grade (P=0.001), higher Ki-67 expression (P=0.001) and lower mean ER (P=0.000) and HER-2 expression (P=0.000). At univariate analysis, tumour grading [hazard ratio (HR)=4.0; 95% confidence interval (CI)=1.4–11.1; P=0.007], nodal status (HR=3.4; 95% CI 1.2–5.7; P=0.000), tumour diameter (HR=2.9; 95% CI 1.7–4.7; P=0.000) lack of PR expression (HR=2.1; 95% CI 1.3–3.4; P=0.002) and HER-2 overexpression (HR=1.9; 95% CI 1.0–3.5; P=0.03), as well as Ki 67 expression (HR=1.7; 95% CI 1.0–2.7; P=0.04) were associated with shorter disease-free survival (DFS). At the multivariate analysis, nodal status (HR=3.6; 95% CI 1.9–6.8; P=0.0001), lack of PR expression (HR=2.3; 95% CI 1.3–4.0; P=0.003) and tumour diameter (HR=2.1; 95% CI 1.1–3.8; P=0.018) retained their prognostic significance, whereas HER-2 overexpression was associated with a trend towards shorter DFS that was of borderline statistical significance (HR=2.0; 95 % CI 1.0–3.9; P=0.05). Our data suggest that lack of PR expression and HER-2 overexpression are both associated with aggressive tumour features, but the prognostic information of PR status on the risk of recurrence in endocrine-treated breast cancer patients is stronger.