Incidence of vestibular schwannoma in Denmark, 1977-1995.

Abstract

Objective: To establish the incidence rate of vestibular schwannomas (VS) (acoustic neuromas) in Denmark.

Background: The worldwide incidence rates of VS vary from 1 to 20 cases per million population per year.

Methods: The nationwide and population-based age-specific, sex-specific, and calendar year-specific incidence rates of VS in Denmark between 1977 and 1995 are presented. Information on cases of VS was obtained from the Danish Cancer Registry and a clinical database situated at the University Hospital of Gentofte. A total of 795 cases were reported during the period of the study.

Results: The incidence rate increased from 5 cases per million population per year in 1977-1981 to 10 cases in 1992-1995; the increase was from 5 to 11 cases among women and 5 to 9 cases among men. The age-specific incidence rates show that VS is rarely diagnosed in persons under 30, but the incidence rate appears to increase among women after menopause.

Conclusion: The overall incidence rate of VS increased linearly during the study period, probably owing to the introduction of more precise diagnostic procedures, increased awareness among physicians and patients of the symptoms of VS, improved registration of benign tumors in Denmark, and the use of data from two sources.