CONCLUSION: The results of this study encourage our belief that some cholesteatomas can be managed using only conservative treatments.
OBJECTIVE: We hypothesized that once cholesteatoma is in a normal environment, its cellular or molecular pathology can revert to those characteristic of normal epidermis. The aim of this study was to determine whether or not common molecular characteristics of cholesteatoma were reversible after removal of inductive factors in experimental cholesteatoma induced in gerbils.
MATERIAL AND METHODS: We induced cholesteatoma using ear canal ligation in Mongolian gerbils. After ligation, the animals in the treated group were managed for 2 weeks. We examined differences between treated and untreated cholesteatomas using terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) staining and an immunohistochemical technique using the proliferation markers proliferating cell nuclear antigen (PCNA) and cytokeratin (CK).
RESULTS: With PCNA and CK 13/16, the untreated group showed positive staining in the suprabasal and basal cells, but the treated group showed weakly positive staining only in the basal cell layer. With TUNEL staining, there were more positive cells in the untreated than the treated group.