Features, which are evaluated for histological grading of breast carcinoma, include all of the following except

Histological grading is based on nuclear pleomorphism; tubule formation, mitotic count Nuclear pleomorphism: Score 1--relatively small uniform nuclei; score 2--intermediate pleomorphic nucleoli; score 3--relatively large prominent nucleoli Mitotic count: Score 1-- < 10% mitoses in 10 HPF; score 2- 10-20% mitoses; score 3-- >20% mitoses Tubule formation: Score 1-->75% cells in tubule forms; score 2--10-75% cells in tubule forms; score 3--< 10% cells in tubule forms Grade Score Favourable 1 Unourable Up to 3 Grade I 3-5 Grade II 6-7 Grade III 8-9 Ref; (page no;534 ) 5th edition of SRB&;S manual of Surgery