Introduction: Angiogenesis is an essential requirement for cholesteatoma growth and expansion. It is mediated via variety of cytokines and growth factors like basic fibroblast growth factor (basic-FGF). Localization of basic FGF in cholesteatoma matrix and its correlation with the destructive capacity of cholesteatoma were seldom seen in previous reports.

Methodology: A prospective immunohistochemical study was employed using 19 acquired cholesteatoma tissues collected during surgery and 8 control tissues from the skin of the deep portion of the external auditory canal. Cholesteatoma patients were categorized into two groups according to their bone destructive capacity following a newly developed scoring system (invasive and non-invasive group). The expression pattern was determined more specifically by the immune absorption test and compared. Moreover, this expression was correlated with the grading score for bone resorption.

Results: Basic FGF was localized in the parabasal and to lesser extent in the basal keratinocytes of cholesteatoma matrix. Highly significant difference was identified between cholesteatoma and skin tissues (Mean ± SEM= 58.53% ± 3.6 in cholesteatoma versus 40.6% ± 3.5 in the skin; P = 0.005). Although the mean expression in the invasive group was higher than non-invasive one, no significant difference between both groups was detected (P >0.05). In addition, no significant correlation between expression and degree of bone erosion.

Conclusion: Basic FGF is overexpressed in cholesteatoma tissue reflecting its vital role in cholesteatoma growth. However, its correlation with destructive potential of cholesteatoma remains questionable. Larger studies are needed to clarify this point which can affect the future management of cholesteatoma.