MKI67 and breast neoplasm: In 2018, Surov et al. reported in a multicenter study that ADC cannot be used as a surrogate marker for proliferation activity and/or for tumor grade in a population of 845 breast cancer patients, including a large variety of breast tumor histology types, including noninvasive breast cancers with a mean ADC of 0.980 and a mean Ki-67 of 12% from six centers with different scanners (different strength magnetic fields, 1.5 and 3 T and different vendors) and different b-values21.