BRCA1 and breast cancer: Glomeruloid microvascular proliferation (GMP) in breast cancer independently adversely affected survival (relative risk 1.9, 95% CI: 1.2–3.0), particularly among women who received adjuvant chemotherapy (10-year survival 27 vs 69%, P=0.0003), and was significantly associated with p53 overexpression and BRCA1 germline mutations.