[Epidermal growth factor in cholesteatoma--the first report: the localization in the cholesteatoma tissue].

The localization of epidermal growth factor (EGF) in human cholesteatoma tissue was examined immunohistochemically, using sections of formalin-fixed, paraffin-embedded tissue with avidin-biotin peroxidase complex method. Thirty-three cases of active cholesteatoma which had abundant granulation and debris were studied. Out of 33 cases, EGF was positive in 32 cases (97%) in the epidermis, 30 cases (91%) in the fibroblast, and 21 cases (64%) in the endothelial cells. In 9 cases of inactive cholesteatoma, on the other hand, EGF was positive in 5 cases (56%) in the epidermis, no case in the fibroblast, and a case (11%) in the endothelial cells. Active cholesteatoma had higher immunoreactivity in the epidermis than inactive cholesteatoma. This suggests that the activity of cholesteatoma is indicated by the immunoreactivity of EGF. Difference of EGF immunoreactivity between active and inactive cholesteatoma was bigger in the fibroblast in the subcutaneous tissue of cholesteatoma than in the epidermis. This gives the reason that the activity of cholesteatoma exists in the subcutaneous tissue. These results suggest that EGF plays an important role in accelerating the growth of cholesteatoma.