Atlas of breast cancer early detection

All invasive breast carcinomas should be graded. Within each stage there is a relationship between histological grade and outcome. The Nottingham combined histological grading system (Elston–Ellis modification of the Scarff–Bloom–Richardson grading system) is most commonly used for reporting. The grade of a tumour is determined by assessing three morphological features: the amount of tubule formation, the extent of nuclear pleomorphism, and the calibrated mitotic count. Each feature is given a score of 1, 2, or 3, and the scores are added to give a combined score. A combined score of 3–5 points is designated as grade 1, a combined score of 6–7 points is designated as grade 2, and a combined score of 8–9 points is designated as grade 3.