New Insights in Pathogenesis and Pathophysiology of Cholesteatoma

Aim: To explore the human papilloma virus's association with the clinical course of cholesteatomas and correlate the surgical findings with the histological features.

Material and Methods: The present study assessed 79 patients with cholesteatoma. Fifty-one patients had surgically aggressive cholesteatoma. This is defined as the cholesteatoma that does not maintain its cystic form and erodes the middle ear ossicles, inner ear, the adjacent bone, and sometimes even the surrounding soft tissues. Twenty-eight of the 79 patients in the present study had simple (nonsurgically aggressive cholesteatoma). This is defined as the cholesteatoma that, usually following retraction, is located in the attic, or, in fewer cases, shows a limited expansion to the mastoid antrum, widens it and maintains its cystic form. All patients underwent mastoid surgery and the cholesteatoma specimens were sent for histological examination.

Results: The clinical course of the cholesteatomas had a statistically significant association (p < 0.001) with the “aggressive” nature found in surgery suggesting that clinical history correlates well with surgical findings. All specimens of patients with surgically aggressive cholesteatoma had characteristic papillary hyperplasia of the epithelium and marked koilocytosis, suggesting papillomavirus-induced lesions. In contrast, none of the specimens of the patients with simple (nonaggressive) cholesteatoma had papillary hyperplasia and there was no marked koilocytosis as only scarce koilocytes could be found occasionally. This difference was statistically significant (p < 0.001).

Conclusion: Papillomaviruses may be involved in the pathogenesis and clinical course of cholesteatomas and their involvement seems to be related with a more aggressive course.