In a multivariable model, adjusted for adjuvant treatment, age and progesterone receptor (PgR), the strongest prognostic factors for BCM were: Nodal status (hazard ratio (HR) = 2.9, 95% confidence interval (95% CI): 1.4-6.1), KiGE (HR = 2.0, 95% CI: 1.1-3.6), and tumour size (HR = 1.9, 95% CI: 0.98-3.8). Here, PGR is linked to blue cone monochromacy.