MMP2 and cholesteatoma: In contrast with Dornelles et al. [65], whose study showed that MMP-2 and MMP-9 are overexpressed in pediatric cholesteatoma compared with adult cholesteatoma, we did not find statistically significant differences in the relative amounts of MMP-2-, MMP-9-, TIMP-2-, and TIMP-4-positive cells between the children and adult groups.