Bloom-Richardson gradingA histological system used to stratify breast cancer, in particular ductal carcinoma, into low, intermediate and high grades for the purposes of diagnosis and management. It is based on three morphologic features:
• Degree of tubule duct formation;
• Mitotic activity;
• Nuclear pleomorphism of tumour cells (nuclear grade).
Bloom-Richardson combined scores
3-5—Well-differentiated (BR low grade)
6-7—Moderately differentiated (BR intermediate grade)
8-9—Poorly differentiated (BR high grade)