Some studies have compared histological grade and tumor biological markers—expressionof estrogen and progesterone hormone receptors; expression of human epidermal growthfactor receptor 2 (HER2); and the Ki-67 cell proliferation index—with ADC values,attempting to identify associations, although the results have been inconsistent andoccasionally contradictory(23).Belli et al.(24) studied 289patients with malignant carcinoma. This evidence concerns the gene ERBB2 and neoplasm.