MKI67 and neoplasm: The results involving Ki-67 in this study are in agreement with Meer et al. [33], Rosenstein et al. [34], and Bologna-Molina et al. [20], suggesting that the immunoexpression index of Ki-67 in UA could be associated with bone destruction and aggressive behavior; however, the differences in tumor morphology may be the reason for this finding, as SMAs form large follicles or plexiform nests, while UAs present only unicystic areas with thin epithelia, thus including great numbers of basal and suprabasal tumor cells with a subsequent increase in the cellular proliferation index.