MKI67 and neoplasm: All of the individual histologic features used for the grading scheme, including MI per 2 mm2 (< 5 v ≥ 5, or < 3 v 3-20), Ki67 proliferative index (< 3%, 3%-20%, and > 20%), and tumor necrosis, were significant predictors of OS, DSS, LRRFS, and DMFS, with the exception of Ki67 proliferative index < 3% versus > 20% for DSS (P = .298, Table 2).