PGR and neoplasm: Notably, low PgR expression levels (HR: 0.41, 95% CI: 0.28–0.61; p < 0.001), high tumor grade (HR: 1.55, 95% CI: 1.08–2.22; p = 0.019), endocrine-resistant disease (HR: 1.60, 95% CI: 1.10–2.31; p = 0.013), presence of liver metastasis (HR: 2.06, 95% CI: 1.34–3.17; p = 0.001), and presence of brain metastasis (HR: 2.28, 95% CI: 1.18–4.44; p = 0.015) were significant independent prognostic factors for decreased PFS in the multivariate analysis (Table 2).