Link between fistulas and cholesteatomas.

Dear Editor:

Cholesteatomas of the paranasal sinuses are very rare, but it is always useful to have detailed case reports (1) that may throw light on the mysterious phenomenon of cholesteatoma formation in general. The tact that the pathogenesis of cholesteatoma has been debated for over a century, and that Viswanatha et al (1) discussed four basic theories, suggests that little progress has been made. It is time, therefore, to critically examine a fifth theory, that cholesteatoma is a misdirected attempt to seal off a fistulous tract or stop a CSF leak. (2) This theory has simplicity and generality, since it applies to several types of cysts and to everywhere in the body.

Applying this theory to maxillary sinus cholesteatoma, one would predict that there had probably been a longstanding small and easily missed cheek fistula. This explains the otherwise puzzling pattern of bone remodeling (1): The maxillary sinus wall was thinned everywhere but only deficient externally, facing the cheek, suggesting a preexisting bone weakness or fistula.

When I checked the terms cheek and fistula in PubMed for clues, there were many references to an odontogenic origin. In the case reported, (1) the roots of the teeth were eroded, consistent with this. There was also a case of tuberculous fistula next to a carious tooth in a 30-year-old Indian man. (3) To confirm a more general link, I checked tuberculosis and cholesteatoma. There were cases of tuberculous otitis, as well as tubercular kidney and spine disease, in which fistulas to the external skin occur. This confirms the link between fistulas and cholesteatomas. Whether or not there was direct evidence of a fistulous origin of the maxillary cholesteatomas, this theory should have been mentioned in this case, (1) and it should be specifically investigated in future cases of cholesteatoma in any part of the body, including the ear.

References

(1.) Viswanatha B, Nayak LK, Karthik S. Cholesteatoma of the maxillary sinus. Ear Nose Throat J 2007;86(6):351-3.

(2.) Gordon AG. CSF leaks and cysts in the nose or sinuses [letter]. Ear Nose Throat J 1986;65(10):486-7.

(3.) Purohit SD, Mathur BB, Gupta PR, et al. Tuberculous fistula of cheek. Oral Surg Oral Med Oral Pathol 1985;60(1):41-2.

A.G. Gordon, BSc

London, UK

Response

In our case there was no evidence of a cheek fistula. In the presence of a cheek fistula, the fifth theory may be considered as one of the mechanisms of cholesteatoma formation.

Borlingegowda Viswanatha, MS, DLO

ENT Department

Victoria Hospital

Bangalore Medical College 

Bangalore, Karnataka, India